Geothermal nightmare
We truly hope you can help us. We had a geo-thermal closed loop system (into the river) put in and it went online March 2012. WaterFurnace Super DeHeater, 4 Multi-Aqua mini-splits (included for AC) and an air-handler (included for AC). 3200 sq ft home with baseboard and in-floor radiant heating. $34,000 and we have had nothing but problems.
The first and most prominent problem right now is the AC – it is now hot and humid here in Central NY. We are looking at the 2nd summer where the mini-splits fan never shuts off in cool mode (it does in heat and dry modes) and THEY ARE PUMPING HUMIDITY BACK INTO THE HOUSE!
Multi-Aqua has refused to civilly communicate with either us or our contractor to help – basically they put the blame on everyone else even though their rep came here to oversee the “fix” of the problem which did nothing. No condensate comes out of the drain tubes after an initial small trickle.
We turned them on this morning with the house at 72 with 55% humidity. Tonight we have 67% humidity in the house and 2 of the splits have one side of the house at 72, but the other side of the house is registering 75 & 78. Even our air-handler which just had a longer trap installed last week (thought to be the issue there) is bringing that side of the house to down to desired temp, but pumping up the humidity.
Can anyone please help. This is just the AC issues, heat is another story. 🙁 Thank you for any help.
PS Our contractor was referred to us by friends VERY happy with their Geo-ground system. They’ve been installing Geo for 30 years – they are dumbfounded by the problems that plague us, but this is no help.
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Replies
Colleen,
If I understand correctly, the miniplit heads are just small fan-coil units. The blower in the fan-coil unit blows indoor air over the cold coil. There is no way that the miniplit head can be "pumping humidity back into the house."
It's certainly possible, however, that your $34,000 system is doing a poor job of dehumidification.
It is unlikely that the problems with your complicated system can be diagnosed over the internet. You're going to have to hire a consultant experienced in diagnosing problems with ground-source heat pump systems.
Sorry to read about your problems Coleen,
may i ask a few questions ?
- what was the proposed efficiency of the complete system ??
- is there a "dehudifying" mode on the splits ?
- are those water or refridgerant driven /? ( probably the latter )
laslty, has anyone verified if the drains from the splits are receiving water ?
Dear Jin,
Thank you replying and for asking questions:
- 1. I'm not sure what your first one means... "the proposed efficiency of the total system." I'm sorry I don't know all of the proper lingo.
- 2. Yes - there is a "Dry" setting on the mini-split remotes and the manual says it is for drying the air when it's too cool for AC.
- 3. These are water-cooled Geo mini-splits driven by the Water Furnace for which the system has been switched to Summer. Our Water Furnace and the 80gal holding tank are reading 56º. So no refrigerant in our system anywhere.
- 4. It has been confirmed that water is sitting in the drain in the unit itself. Last year your hand would get wet if you held it up in front of the above pictured unit. Last year we would get an initial trickle of water from the drain tubes outdoors for about 30 minutes, then it would shut down and you'd get just a drop here and there.
I have wondered if it is possible that because the fans never shut off, could it be causing some kind of air-lock up in the unit itself so that the water never drains out? Again, Thank You!
So you are saying that the fans in the fan coils are never shutting off even after the cooling load is satisfied, thus re-evaporating much of the water that had condensed?
Dear Martin,
I can assure you that these splits ARE putting humidity back into our home. See attached pics taken yesterday from starting point, to an hour or two later, to end of day... I'll only attach for one of the 4 units the last 2 taken last night. These splits and the air handler were only added onto our system for AC, our heat is supplied via baseboard and in-floor radiant. So I would assume the dehumidification would have to come from the splits and air-handler as they work to cool our home during the season when humidity is an issue. Is that correct?
I can't believe this... we refinanced our home for 20 years and have a 25 year NYSERDA loan to pay for this. :( How can we find an consultant?
Thank you for taking time to answer. I came here because Multi-Aqua refuses to offer any help for their dysfunctional units and our Contractor is at a loss. I appreciate your time.
Yes Aaron and Thank you for replying!
This was my first concern and question to our contractors and Multi-Aqua. Our contractor did not know this in advance of installing them, nor did I. I would have refused them for that fact alone - we invested in Geo for the "green" and energy savings. It was explained to me by Ralph Ferria, owner of Multi-Aqua, that they purposely programmed them to stay on in Cool Mode to create a more comfortable climate within the house.
Colleen,
Unless you have a ventilation system that is introducing outdoor air into your house, the humidity is not being introduced by the system. The humidity is already in your home.
Here's what is happening (I think): the cooling system is failing to remove as much humidity from the indoor air as you would like.
Yeah, it doesn't make any sense - there's no source of introduced moisture. Unless my understanding of the technology is deeply flawed (an all too credible possibility, sadly) Martin has to be right. The moisture is coming from somewhere else (or just isn't being removed very well). Lots of moisture looking for condensing surfaces (like your hand).
Colleen: The mini-split head type coils aren't "putting moisture back", they're merely not removing the moisture- "not taking moisture away".
This is a design & control issue with the system. Whether it's refrigerant or chilled water in the coils it should be capable of taking the coil temps WAY down, unless the blower speed is way too high for the volumes being pumped through the coil. If you have 67%RH @ 75F room air entering the head (as indicated in the third picture), that corresponds to a dew point of 67F: As long as the coil is substantially below 67F you will be getting substantial condensate formation on the coils, real dehumidification. If the blower speed is too high for the fluid volumes & temps it raises the temp of the coil and very little (or no) dehumidfication is taking place. But with 56F water in your chiller tank, it means you probably are going to get much dehumidification unless the pump is running high volume, and the blower is running on it's slow.
Measure the temp of the exit air- if it's only 65F or so it means you're getting very minimal dehumidification. The air blowing out of the head needs to be under 60F to do much in the way of real dehumidifcation, and 50F is even better which may take 40F or cooler chiller water. If you can hard-limit the blower speed to "low", you'll probably see cooler exit temps & better dehumidification even with the 56F chilled water, unless there is a feedback & control situation that scales back the pumping rates when the blower slows. Whomever designed the system SHOULD be able to figure out what's going on, and be able to adjust it to give you better "latent cooling" (== dehumidification) either with the 56F water or cooler water.
But mind you 56F is what you really want for the dew point of your room air- 50%RH @ 75F has a dew point of 55F, and 50% RH is the high end of the "healthy" range for those with allergies or skin-fungus issues, though 60F dew points can still be considered comfortable for some. You'll NEVER get there with 56F chilled water or even close, since the coil temp will always be higher than the chilled water temp when it has 75F air passing over it. With 45F, or even 40F water it should work just fine.
If they can't figure this out they should hang up their license and go into another line of work. You may have to find a better contractor/consultant to debug this for you, but I'd be shocked if it takes more hardware to get there- it should be just an adjustment possibly a SOFTWARE adjustment, depending on the control setup. The plumbing may look like something NASA cooked up, but I assure you, this isn't rocket science, and designing for good latent cooling is a standard requirement for central NY's climate, and if they set it up intentionally for 56F water or set some other system parameter such that 56F chilled water is the limit, they've really screwed something up.
Coleen :
- by effiency i meant if you knew before investing a suggested efficiency rate for your installed system ..
meaning how much more efficient than electricity your system is on a average for cooling and heating loads . ( example : 3 for 1 average efficiency on heating system VS baseboard electrical heating )
they call this COP ( coefficient of performance ) in the jargon.
- your mini splits must be refrigerant driven if they have a drying mode,
and must be able to evacuate all of the ( drain ) condensate
The bottom pan should be sloped toward a drain point as so not to leave much water standing for the fan to pick it up , i'd document that and discuss with the manufacturer of the minis.
Again someone more experienced than me might chime in, but i do not believe it is possible for any of your equipment to actually raise the RH% of your air.
It might condensate it and redistribute it, but it wouldn't drive it up.
What is used for air recovery/exhanger ??
Does humidity level stabilize if you turn everything down ? might try and document this also.
I am going to stretch here and say that there is no way 56 degree water is properly cooling the house. I looked at this stuff before, and it made no economic sense to me. I would lower the water temp to as low as you can[uhhhh 33 degrees?] and see if it improves.
[edit] if you lower the temperature of the air without dehumidifying it , the RH goes up
"I am going to stretch here and say that there is no way 56 degree water is properly cooling the house."
D'YA THINK!?!
You probably get at best a 5F delta-T between the average coil temp and the dew point of the exit air out of the coil, and a 10F delta-T in water temp across the coil. So with 56F entering water temp and 66F exiting water temp the average water temp is about 61F, which means the dew point of the air won't be dehumidified below a dew point of 66F or so. We don't have the specs on the system components, flow rates, etc. but the notion that you can get adequate latent cooling with 56F water no matter WHAT the flow rate or delta-Ts on the coil (either air or water delta-Ts) is bonkers- yer kinda stuck. You need a 55F dew point max on the exit air, and it's simply impossible to do that with 56F water entering the coil, even if the coil were a perfect heat exchanger that could operate at an infinitessimally small or even zero delta-T.
It's pretty hard to chill the water to 33F without icing up the heat exchangers in the tank, but I'd hazard that 45F is do-able, and that would provide considerably better latent-cooling that what's possible with 55F water. Given the fairly cool ~47F subsoil temps in central NY (see: http://www.earthrivergeo.com/img/geothermal-article/geothermal-subterrainean-temperature-contour-map.jpg ), probably much cooler in the earth loop at the end of the heating season like this, one should be able to make 45F chilled water extremely efficiently. At the end of the cooling season your earth loop temps might be well north of 47F with a lowered net efficiency, but the heat pump shouldn't have to work very hard at all this week. If they can't make 45F chilled water without an ice-up problem, the system design has a fatal flaw somewhere, but fixing it is probably a plumbing problem, possibly a pump swap.
I don't pretend to be a geo-hydronics designer, but I can read a psychrometric chart- the fundamentals are a bit off here. Make colder water- it'll never dehumidify adequately until you do.
Everyone - I am so grateful for the time you are taking to help us!!!
Martin - there is no ventilation system putting outdoor air into the house and all doors/windows are closed. The humidistat reading in the pictures is all we have to go on... we see it as 56% in the morning (with house completely closed), we turn the system on and Voilá! In an hour and a half the humidistat is up several % and by the end of the day it is up 10-12%. So humidity is building as the day goes on and the system is simply not taking it out ??? Perhaps this is a good time to mention that last summer it we would have higher humidity IN the house than outdoors! I don't understand how that can happen if it's not adding to it, although I do understand your thought and thank you for it.
Dana: The Water Furnace is set at 56º for this trial and error session. Last summer we had the same results with it set at 40º, 44º, 48º, 50º, 52º and then 60º and 56º were tried these past 2 weeks... In conjunction with these testing cycles, we have tried also setting all remotes to Low fan settings. The Air Handler does not have a high/low fan setting for heat or cooling. Are you saying that we need to set the remote temp for like 58 or 60 to get the humidity down? The house cools quickly, and the contractor questioned Multi-Aqua if it could be cooling the house too quickly so that warmer moist air is no longer going over the coils, therefore no condensate being created to be drained away? Multi-Aqua insisted they were just installed improperly even after they Rep finally came here last June to see for himself.
We never had to do this with the Fujitsu (refrigerant) mini-splits this system is helping to replace. We set the remote at 72 and it would cool the house quickly to that temp and the humidistat would read about 45% humidity.
(We had lightning hit the river and take them out 2 years ago - which is why we thought we should invest in green technology since we had to replace them, and get rid of the window AC units that took care of what the Fujitsu's didn't cover.)
THANK YOU for your thoughts on it being a SOFTWARE adjustment. This is exactly what our contractor has felt it must be because of all the things they have tried which do not take care of the issue. Multi-Aqua refuses to even discuss this but they are the only ones who could remedy a software concern. (Contractor had never used Multi-Aqua units before but went with them because they were a sub-division of Trane - although I can find no written connection)
Jin: We were told by 2 different Geo companies (who we got quotes from) that the system for HEATING would pay for itself in 7 years. Adding cooling to the system it would take 11-12 yrs. NYS did a Cost/Savings Ratio and we fell well within their parameters, although I do not know what the numbers were. These were based on past 20 years climate data for our area and current electricity/propane and fuel oil costs for our oil boiler driven baseboard & in-floor radiant heat, and included the electricity the previous AC cost us. I hope this is kind of the the info you were looking for.
- These really are water-chilled mini-splits. I don't know about the drain pan within the unit but I do know we never have much if any condensate coming out the tubes outside the house where they are supposed to drain off to. I have asked if the drain in the wall unit is not sloped enough or large enough or if it can get air-locked, not letting the water out after an initial trickle but no one has addressed this that I am aware of.
What Dana said above makes sense, which unfortunately leaves us back with it being in Multi-Aqua's court and have continually refused to discuss/help.
Lastly, in shutting everything down, humidity does not stabilize unless we open up the house and it is lower outdoors. We have documented this last year with pics from Weather Station which died last fall.
Please know how grateful we are for you all taking the time!
Thank you, Dana - based on your previous post to which I've just replied, we have just lowered the tank's setting to 45º. I don't hold much hope as you will see we had done that last summer, but we have again and I have lowered all remotes to LOW fan speed on the mini's. We shall see. I'm not sure what the river temp is right now, where our geo-field resides about 10' down.
We have one more high humidity/high 80's-low 90's day to go with tomorrow before temps drop to the 60's on Monday. I hope we will have more info to go on by Sunday.
This isn't really what you asked about, but in the course of all this mechanical work, was any air-sealing work done? Have you had a blower door test, and if so, what was the result? If you have a lot of air leakage, mechanical systems will be struggling to keep up.
Coleen:
- 7-11 years ?? how high ur energy bills used to be with the mini splits ?? because 34K / 10 year = means u need to be saving 3400$/year which i highly doubt.
- what is the connection with the river temp ? aren't u using a heatpump and the river as heatsink??
- about what Dana pointed out, if you are @ 65 RH% + and your aqua mini split temp is in the 50f or lower, you should be experiencing a serious quantity of water coming out of the drains
can you dispose of some sort of recipient at the drain end and verify the daily condensate removal ??
Can't you remove the plastic cover on the aqua mini and look for its operation ?
( see how cold it is, how much condensation there is, where water goes .. )
I would seriously be looking in the water drain path to see what is happening here.
So no air exchanger ? when the splits are on, is the main air system on also ?
don't forget that humidity is pushed in through cracks and some materials when it is high outside and under some other conditions ...
Unless there is a leak somewhere near an airstream in one of your device,
it is pretty much impossible that the equipment is raising the humidity.
You might have 2 seperate problems that are working together here.
Coleen -
My seven cents, including some basics; hope the repetition / rephrasing helps, apologies if too basic for some:
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1. 'Humidity' vs. Relative Humidity: When you seed the '% humidity' going up on your portable sensor, it almost surely is telling you the 'RH', meaning _relative_ humidity, not _absolute_ humidity. Because colder air can't hold as much moisture, as air temp goes down, RH can go up, even if (some) moisture is being removed from the space. So it actually _feels_ wetter, because the air is closer to its 'dew point', where it become 100% saturated and some of the water has to 'fall' out (sticking to any colder surface, becoming a fog, or raining...e.g., drips or stains on the ceiling / walls). Lowering the cold water temperature is going to be necessary to bring the air to its dew point, strip the moisture out, and then send the colder, dryer air back into the room to warm up a bit.
2. Fan Runtime: Some debate on this, but better if fan doesn't run continuous; best perhaps if off as soon as chilled water stops circulating. This is (part of) the 'software' issue that we're referring to. See the recent 'Climate-Specific Air Conditioners' article on this website for lots of discussion. Your contractor should be able to work with Multi-Aqua to fix this issue with the hardware and software you already have. If for some strange reason that proves impossible, perhaps buying a device _like_ the one in the article could add that capability.
3. Run only one head: Have you ever tried running only one of the mini-split heads? This should slow down the rate at which the house air cools, keeping the coil cold for longer, and therefore removing more moisture / doing so more efficiently (continuous operation of the cold water loop, instead of cycling).
4. Coil Temperatures: What is the water temperature as it enters the coil? And when it exits? If you had the problem even with the tank at 45degF, it could be that some installation problem is warming the water before it even gets to to the head, reducing its effectiveness; or that the water is arriving cold, but the flow is being blocked (e.g., if there's a high 'delta-T' ('change in temperature'), so the very little water that is exiting is almost at room temperature). I recall an article here recently about a house where the uninsulated heating pipes went through an un-conditioned garage before reaching a bedroom that...no surprise...was never warm enough! There are a variety of fun tools you can buy to measure these temps (and check the flow); but you shouldn't have to - your contractor should already have them.
5. Air Sealing: David M's comment (among others) on air sealing is important: If warm, humid air is sneaking into the house through lots of little gaps, the AC system will struggle to keep up. Lots of good resources on this site about the topic; but best to hire someone (HERS rater, etc) to do a Blower Door Test to see how tight your house is, and where and how big the holes are. They can check other things to help find the problem too...
6. Proper Drainage of Condensate: Any water dripping from the coil has to go into the tray, which should slope to the drain pipe, and then be carried outside (via a P-trap, like under a sink, to make sure bugs and air don't come back in). If the pipe is blocked anywhere, or the tray or pipe slopes the wrong way, the condensate will just build up in the house, and then re-evaporate. By dis-connecting the pipe at the end of the tray an putting a bucket under it, you can see what's actually going on (and get some distilled water for your garden!). Might need to clean out the drain line. But since you're not seeing drips around the head, it's unlikely that this is the major problem.
7. Other sources of moisture: All sources of moisture have to be handled; kitchens, bathrooms, roof and window flashing most obviously; also, basement walls and slabs or crawlspaces, etc. From what I can see, you're on a hill, close to a lake; water could get in from runoff above the house that isn't being carried away properly (bad grading/drainage, missing or non-functional perimeter / footing drains, etc), or work up through capillary action. We can't help diagnose without know more about the house, but a building contractor (not just HVAC installer) can help. If you have an exposed concrete slab or wall, tape a piece of clear plastic to it; if you see condensation under, moisture is coming _in_ through the concrete; if condensation forms on top, it's from somewhere else. See also the article here:
'The Worst House I Ever Audited Was Built in 2008'
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Ok, that's probably more than enough...as Martin said, it's _unlikely_ that your problem can be properly diagnosed by volunteers over the internet; but hopefully you are learning what to look for, and what to ask those who can be there in person.
Sometimes it ain't easy being green! But your intentions are admirable; stick with it and let us know how things play out; we always like to hear the 'whodunit', even if it proves our hunches wrong!
Everyone, there is so much great info here so I will address all things brought in this one post.
1. Blower Test: David M - a blower test was done and the results were that our house is very tight... the only issue we had was at a pocket door - testing fella said that if it weren't for that one spot, we would have failed the test, making our Cost/Savings Ratio undesirable in NYSERDA's viewpoint. This is surely NOT the reason we are having humidity issues in the house to the degree we are as this pocket door has been here for 23 years, but we will call to have that addressed this week. It is where our old house met the new addition. We are thinking that a Spray Foam Insulation contractor would be the way to go unless anyone here has other suggestions - which I can only assure you all that we are SO appreciative of.
2. Payback: Our utility bills were VERY high. Fuel Oil, folks, need I say more? The budget estimation for Fuel Oil alone from Mirabito came in at nearly $5k for 2011-12 heating season - which is why we also felt we had to do something, so with the lightning strike and Ins replacement of the Fujitsu AC (2 splits/1 condenser - electric) this is what pushed our rate-of-return to 7-11 years. Fuel oil never did get to $6/gal that was projected, but it did hit the upper $4 range which we had to pay as our Geo did not go online untll St. Patrick's Day 2012. Then add in Electric & Propane (dryer/hot water/cook top)
3. Fan Run Time: The Fan run-time is a huge issue to me (for cost and having to listen to it) and we will read the Climate-Specific AC article today! Thank you!
4. Running 1 Head: Last summer we did run just 2 of the 4 mini's to see if the house cooled more slowly, would that diagnose/solve the issue, but it made no difference. This was back when the tank was set to temps in the 40's, too, with LOW fan speed setting on the remotes.
5. Water Temp In/out Data: (9:30am 6/1) We reset the tank yesterday to 43, it's reading 46 now
Mini1(LR): IN=53 OUT=62
Mini2(Loft): IN=58 OUT=71.8
Mini3(Office): IN=69 OUT=73
Mini4(BR): IN=69.4 OUT=71.8
6. Mini-Split Drainage:
Level or Sloped: A check now of the "level" of the drain within the mini's today shows 2 downstairs level but "looks" like may be slightly tilted away from the drain hole... can't tell if inside construction is same. Upstairs the 2 minis level shows they are tilted toward the drain on the inside.
7. Piping Insulation: Everything we see indoors is fully insulated. There are lines outdoors that go up to the splits and from where the drain tubes come down... see attached pics. We were told they are filled with spray foam to insulate them and I saw them doing some of it. It does bring warm air up when in HEAT mode in the winter.
Today set collection pails under the 2 mini-split discharge points and as I close this post, the only condensate we are getting is from the Loft mini which appears from the data here to be the only one that is leveled properly (toward the drain hole on the inside) and with more proper temps for humidity control.
??? Should the remote temp be set to what a normal person would expect... 72 for desired room temp? OR is it supposed to be set at what temp should be coming out of the split to cool the room? Based on the RH/AH discussion, I set them all down to 60 yesterday about 6pm. This doesn't make sense to me because what would cause the unit to finally shut off /stop calling for chilled water at desired room temp? They are not wired into the main thermostats. We did shut them all down last night at 11:30 and the house was averaging 74 between the 4.
8. House has good drainage - we sit on mostly gravel. With french drains, gutters and the hill, and running a dehumidifier (because of the river) in both basements, humidity in the house is controlled nicely in the summer when AC works properly as it always did with the refrigerant system we had in the past... which all dropped condensate outdoors at an impressive rate.
9. Does anyone know of another company who makes chilled water mini-splits for Geo?
Hi Colleen,
By the way ....Great Q&A Title
You wrote: " the only issue we had was at a pocket door and the testing fella said that if it weren't for that one spot, we would have failed the test, making our Cost/Savings Ratio undesirable in NYSERDA's viewpoint."
So ...
the Rater fella is telling you that Leaky is a good thing and Not-So-Leaky is a "Fail"
and an exhaust fan on a timer would have broken the budget?
So sorry - I deleted this posting as it had gone up accidently so did not have all data. I reposted below.
Hi John - :) Kind of... he was saying our house is very tight, everywhere but this one spot... but for us to qualify for the low-interest rate NYSERDA "green" loan program the numbers had to come in at a certain number or below.
For the past decade we have been doing what we could to be as green as possible: Energy Star appliances, new windows, proper insulation, caulking, vapor barriers, etc. We had to go for the loan because we had already re-financed the house for this, but needed more to go Geo.
I took a look at the Multi-aqua materials online, and the spec sheets appear to show 42F and 45F water temps for rated performance. As discussed above, there is a HUGE difference between those numbers and 54F in terms of humidity removal. Two of your units look to be operating with very warm incoming water and a very small temperature split, those will do almost nothing. There are also flow rates to verify. I would get someone with temperature measuring equipment to see if you're even close on the water or coil temps. An IR camera would make it very simple to get at least a basic overview of the operating characteristics.
Thank you David. We measured the temps with Kintrex IR laser thermometer.
Just heard that the guy who installed the system is coming Monday and contracting company owner is coming this week with an HVAC specialist!
Thanks to this forum, we feel far more educated and capable of posing better questions to these folks, sharing our data this forum led us to collect, then to Multi-Aqua once more. We will definitely have them recheck flow rates, and all of our data-sheets for the entire system are here.
We will let you know what happens. Again, THANK YOU one and all.
Colleen, no offense, but it is going to be very hard to get accurate temperature measurements without a better tool. Low-end IR thermometers usually have a wide field of view and fixed emissivity, and I suspect you are trying to shoot small-diameter copper tubing with it. Hopefully your installer understands this when he comes out to check, and brings appropriate tools. Does the equipment manufacturer have anything to say about how to check performance on their gear?
This story is a stain on the industry and should be a cautionary tale for homeowners. If you are stretched to your financial limits on a project you should probably stay away from the more complex non-standard systems, or at least from installers without a well-documented track record in that field. And yes, custom construction is a crazy business, the only manufacturing industry which to one degree or another only builds prototypes, but we can at least do the more esoteric experimentation on our own dime, or with a well-resourced client who knowingly and willingly enters into the enterprise.
How many ductless minisplits can you buy for $34,000?
Colleen,
In post #4 you said that you hand would get wet when held in front of the unit. Do you mean to say that droplets of water are being blown out of the unit? This seems like a clue if true.
David - thanks for the info on our IR - was just trying to answer the question with the tools we have on hand. I assume what we got is close enough to be a little helpful. Multi-Aqua, the equipment manufacturer, refuses to acknowledge there IS a problem, much less respond civilly to requests from either our contractor OR from us, the end user.
James - Thank you for your willingness to offer an opinion but I respectfully disagree. We did our homework, chose a company that was recommended to us by a friend who used them for their GeoThermal system AND has over 30 years in the business. They are the leading installer of Geo-Thermal in Western NY. When you get a quote from a reputable contractor, then refinance your home and get a State sponsored low-interest loan to cover it, you shouldn't have to have a big buffer in your bank account as well.
Martin - we got 4 ductless mini-splits and an air-handler with a Water Furnace Super De-Heater, and an 80 gallon holding tank, along with installation of geo-field into the river and air ducts for one section of our home where mini-splits wouldn't work.
And Bill, thank you for your question. The answer is YES! If you held your hand in front of the mini pictured above last summer your hand would get wet with droplets of water being sprayed onto it.
Colleen - "When you get a quote from a reputable contractor, then refinance your home and get a State sponsored low-interest loan to cover it, you shouldn't have to have a big buffer in your bank account as well."
I couldn't agree more, which is why I called your situation a stain on the industry. Whatever his reputation and experience, it seems pretty clear that your contractor has not fulfilled on his responsibilities. I meant no criticism of your role in this, but I suggest that when it comes to the installation of complex systems such as this normal levels of homeowner due diligence may not be enough.
If the mini head is spitting water at you, it's water that has condensed on the coil and is being blown back off by the fan, rather than draining. It's not moisture from outside.
All:
1. Coil in/out temps: How long had the system been running at 9:30AM? The number are maybe not accurate from the Kintrex IR; but any guesses as to how far off? The wide range (7degF to 24degF delta T from tank to head) seems very odd...this seems the most important clue, but need better measurement before jumping to conclusions. Two come in cool, and warm up (maybe good, unless it indicates inadequate flow); the other two come in warm and leave a hint warmer...! Measuring temp/RH at the head intake (return) and outflow (supply) sides would help establish in/out dewpoints?
2. Heads spitting water: I assume this was last year, at higher fan speeds than are being used now; not a problem anymore, correct?
3. Condensate drainage: Is the current piping new, or old? I don't see p-traps at the end (maybe they're interior somewhere?); humid air could be coming in from outside (with additional heat from solar gains on the black building paper? Or are those construction, not finished work photos?), re-evaporating the condensate as it tries to get out... My idea was to disconnect the pipe at the head, if at all possible (can be messy), to really know what's leaving the pan...but do other things first. If your house is indeed tight (was it tested after the new system was installed, or just before?), shouldn't be a major problem.
4. Any chance there's air in the chilled water system that could be causing a circulation problem?
The mystery continues...
Droplets of water blowing out of "minisplit" heads is unacceptable.
Need ACCURATE entering and leaving water temps at each active head; same for air temps in and out of each head.
As has been remarked, IR won't cut it for the level of accuracy needed to resolve what's happening here.
Hi Curt & David M.,
I'm not an Energy Rater or a technician....just a curious Architect.
but.. I thought IR thermometers were reasonably accurate as long as you understand the Cone of Vision ?
My $50 Raytek MT6 has ratio of 1 to 10
If I want to measure something that's 1 inch wide ...
I assumed I could measure from 10 inches away?
Are IR thermometers really that inaccurate ?
Google emissivity.
Don't get me wrong - IRs are great for quick and dirty diagnostics, but this situation needs contact thermometer(s)
John, there are a couple of problems with using a cheap IR thermometer for this type of critical temperature measurement.
First, the cone. Your unit is 1:10, so if you want to measure something that's an inch wide WITHOUT accidentally *also* measuring anything in the background, you need to put it 10 inches from the subject. If the OP is trying to measure smaller diameter tubing (and I don't know that she is, just guessing) then the unit would have to be closer in order to avoid contaminating the reading with whatever's behind the subject. Problem is, focus is critical to accurate temperature measurement, and I don't know if these units are focused at that close distance. If not, then accuracy goes down and you don't even know it.
Then there's emissivity. It is very hard to get accurate temperatures off of shiny metal, such as copper tubing, without doing something to adjust for it. If you point your IR at shiny copper, you are getting only a small portion of the reading from the tubing itself, and a large portion from whatever's reflected in the tubing. In a lot of cases you yourself are reflected in the subject and so your skin temperature is a large part of the reading. The simple solution is to put a piece of Scotch #33 electrical tape on the subject, set the 'e' of your IR for about .95, and take your reading from that tape.
Then of course you have to adjust for the effect of air temperature on the outer surface of the tubing.
If you really want accurate temps in this case, the best tool is a high-res IR or a pipe probe connected to a thermometer. In this case, a couple of pipe probes and a two-channel thermometer might be ideal. I'd like to hear from the OP about how the technician does it.
Take a look at the attached images. The first one shows a piece of stainless woodstove chimney pipe in use. Part of the surface is shiny stainless, part is the manufacturer's label on the pipe. Note the really big difference in readings. The second image shows a bunch of copper piping around a water heater and solar tank. The temperature readings are being taken from pieces of tape around the pipe. In both cases, the metal areas are a lot closer to "room" temperature because the readings are mostly reflected.
Thank you Curt and David
and David, thanks for the detailed explanation and illustrations
Colleen: The remote sets the room temp setpoint. I assume that without other sensors (such as a wall thermostat accessory) the room temp is sensed at the wall unit's incoming air temp.
Bumping the water temp down to 45F was a critical first step- if it's spittin' water at you it's condensing, taking moisture out of the air, but failing to drain properly, as David and others have noted. (Improper leveling of unit, clogged/crimped/corroded drain? Any number of things can interfere with the the condensate drain.) Bumping the water temp down to 40F would be even more drying, but at some point you may run into icing conditions on the heat exchangers. With a tank setpoint of 45F you probably won't have those issues, and it SHOULD be able to provide reasonable latent cooling.
High accuracy on temperature measurements are rarely necessary for debugging this. It clearly wasn't drying the conditioned space because the water temp was being delivered at way too high a temp fro much moisture to condense on the coils. Now that you've fixed that part of the problem, if it's spraying all that water back into the room as liquid rather than draining away, the water re-evaporates into the room. Fixing the drainage issues should be your only remaining obstacle to getting at least some humidity relief.
The fact that the cooling is in self-contained coils rather than ducted air you don't have air-handler driven infiltration to worry about, so even in a fairly leaky house it should work-mostly, provided the coils were sized reasonably for your air volumes and loads. Air-sealing the house may be a very good idea, and will lower both the latent & sensible loads, that's a secondary issue, probably well behind those of running the coils cool enough, and getting the drains to send the condensed moisture somewhere else other than splashing it back into the room.
BTW: Referring to the chiller coil wall units a "mini-splits" is confusing, since a mini-split is a refrigerant based system with it's own compressor and an outdoor coil & fan. While the hydronic coil heads LOOK like the interior heads of mini-splits and provide similar functions, they're technically not the same. MultiAqua also sells air-source heat pumps with self contained refrigerant loops, to be used with the chiller coils, but you don't have one as part of your system, and are using the geo & chilled water buffer tank instead. If you call them "non ducted fan coils" (the way the manufacturer does), or "fan coil units" there is no ambiguity.
Martin: $34KUSD would buy about 10 installed pretty-good 3/4 ton ductless mini-split heat pumps in my neighborhood, but let's not be mean about it, eh? One of the real risks with any ground source heat pump is that it's a custom system, with many ways to screw up the design, whereas a ductless air source heat pump is a "system in a can", an already-designed pre-engineered system, with none of the Rube Goldberg Contraption aspects of many geo system designs. That's not to say installers can't/don't screw it up, just that there are fewer ways to screw up, making screwups less likely, and debug is simpler too.
Dana,
I agree that Colleen's use of the term "mini-split" to describe the fan-coil units is confusing -- which is why, in my first response to Colleen, I tried to establish "fan-coil unit" as a better description.
And, as you probably know, my question ("How many ductless minisplits can you buy for $34,000?") was rhetorical; it was a response to James Morgan's description of ground-source heat pump systems as site-built prototypes. I think we all agree on that point -- but, needless to say, the lesson is for other GBA readers, not Colleen.
Everyone, again, thanks so much for your continued discussion on our issues here. We are learning from you all, even when you aren't replying to me.
1. James, thanks for clarification as to what you were trying to convey. It's much appreciated.
2. It seems I was inefficient at describing our humidity issue and I apologize... We feel our fan-coil units (sorry for the mini-split term previously used - thanks Martin) has never drained properly, thereby pulling water out but then blowing it back into the room.
3. The fellow who originally installed our system was here today in advance of the owner who is bringing an HVAC specialist later this week. He did a number of things:
a. He listened.
b. He reset the tank controller (Ranco) to 38º as there was a 5º differential on the tank itself (42º).
c. He checked all of the pumps and found one set at low (he understood why a previous tech had tried that - but it obviously didn't work - trying to slow down the speed of cooling in hopes of pulling more condensate out I believe was what he said) and found 3 set at medium. All are now set to high.
d. He measured the intake and out take air temps with the IR saying he didn't have room to get a pipe-point thermometer into the fan-coil head itself for measuring but he was going to use the latter therm to take readings at the Water Furnace area and for the air-handler in the other section of the house. I had to leave for an appt so do not know what those results were. He said he was trying to gain a 15º temp difference between the two.
e. He did get air out of 3 of the 4 units AGAIN! Every time they have come for these units, air has been an issue. We have a typical spiral valve on the main 80 gallon tank and in Jan they added another automatic air flow valve.
He left hoping that this will maybe be the AC fix that is needed but it is 63º here today with low humidity so we need to wait for warm muggy air to return to see.
I did question him on what is insulating the pipes that run up the outside of the house and house the drain tubes. The pipes have the foam insulation that is around the pipes throughout the interior of the house, they are pushed tight up to the house with silicone caulk on the sides, they have the foam-in-a-can insulation (my term, not his) at the tight joints and where it comes out of the house and then is packed in either R9 (I think he said) or R13 (he couldn't remember which) around everything, then pressboard creating the housing which is also caulked down the sides along the cedar shakes, tar paper as you see. We have not put the new shakes up until we are sure everything is working properly, but they are here just waiting for that to happen.
I will let you all know how this pans out after the HVAC specialist visits. Again, so many thanks go to all of you! Oh - and our install-guy went home with this website info, too. :)
By " He did get air out of 3 of the 4 units AGAIN!", you mean there was air in the chilled water loops forming a bubble at the fan-coils? That would make the chilled-water flow to those fan coils somewhere between low & zero, severely impeding cooling performance. This is something any "wet-head" hydronic system designer/installer should have known about and taken measures to prevent, usually with an "air scoop" on the circulation loop &/or an automatic air vent at the highest point of each loop. Air-purging hydronic heating & cooling systems can be a real PITA sometimes, but once you're "there", it shouldn't need to be repeated until you break open the system again. Hopefully with the new air valving/venting that problem won't be recurring.
If the water in the system is at low pressure air can sometimes get into the system via osmosis, or sometimes by negative pressure seepage at the highest point in the system. Most hydronic heating systems in 2 story houses are set to 12-15psi at basement-boilers, which keeps the pressure sufficiently high that the pressure is high enough to prevent this even at the second story radiators. Having sufficient system pressure is just as important in chilled-water systems with fan-coils high on the second-floor walls, with the buffer tank in the basement.
Dana, I've seen your posts/comments on other sites. What is your profession? Where you located? Do you do consulting?
Sal: Though my degrees are in physics & math, I work as an electrical engineer (electronics)- mostly analog circuit design, though I'm currently learning Verilog (a digital hardware description language) to become more useful within our tight knit design group. (Given the rapidly progressing state of the art of DACs & ADCs the amount of precision analog design work required for many things have been much reduced over the past 25-30 years.) I live & work in MA, but our clients world-wide, not just local.
The building-science, HVAC, efficiency & energy-use/energy-policy stuff is just a hobby, but a serious hobby. I have spent plenty of time over decades helping friends & family sort out their home construction & energy-efficiency issues, including interior lighting/daylighting design, passive solar, etc. I take climate change & energy resource issues seriously and consider the responsibility for dealing with them both personal & political. The inability of the US feds to make consistent policy on this stuff is a source of frustration- it's not as if the handwriting hasn't been on the energy resource wall for at least 40 years now. The fact that the energy-returned on energy-invested (EROI) for gas & oil is now below the rising EROI of utility-scale wind power (even with the size of shale-oil/gas reserves) makes me bullish on wind, but makes me wonder how the US could still be so DYSFUNCTIONAL to remain heavily dependent on those energy sources, long after the decline became obvious.
Even with a massive-scale ramp up there isn't enough wind resource to displace very much fossil energy use (particularly in the space heating or transportation sectors) without treating efficiency upgrades in like an even greater emergency. Those singing "Happy Days are Here Again" over the natural gas glut have been sniffing the fumes- the EROI of that natural gas is less than 10% of what it was in the 1950s, and it's falling over time. The EROI of scalable liquid biofuels or bitumen-sand oil is abysmal. No matter how big the resource, an average energy portfolio EROI average much below 10 will not support the standard of living or society the first-world currently enjoys. The worldwide EROI of oil & gas combined, all sources is under 20 and falling. PV solar is over 7 & rising, large scale wind is over 18 and rising. The sooner the US builds-out the very substantial wind resource, and builds-in building & transportation efficiency, the cheaper it will be, buying us some time to improve EROI on all fronts, but particularly on low-carb technologies. High-carb coal use still has a pretty good EROI, but when "clean coal" carbon sequestration of the exhaust is required for global warming mitigation it drops to the sub-10 range (numbers on clean-coal are squishy, with so few clean-coal powerplant designs having been implemented, most of them in China, without third-party verification of cost & performance.) If you want to wade a bit further into the weeds on EROI estimates, this overview is pretty brief & readable for those who aren't already energy-policy-nerds:
EROI of Global Energy Resources
Bottom line: Along with personal transportation, houses and buildings have to become MUCH less energy intensive over the coming few decades for our grandchildren to have a shot at a decent life, and waiting around for some pie-in-sky technologies to be developed to save the day is folly. Fix your own energy use and carbon footprint issues as soon as you can- it won't be getting any cheaper (with or without subsidy.) To the extent that I can nudge people in those directions on a lowest cost/least damaging basis by posting on blogs, I give it a shot. Just as with friends & family, sometimes it sticks, but often(or perhaps usually) not.
Most people don't share my sense of urgency on these issues, or figure it's somebody else's problem to solve. Others are willing to spend $34K on mechanical systems toward similar ends, but usually without doing the full cost/benefit math comparisons between alternative ways of spending the capital. In some cases spending the first $15K on building envelope upgrades and the next $10K on PV would have brought loads to within $5-8K of ductless air source mini-split territory, with a lower net purchased-energy use than the GSHP system under discussion here. Sometimes GSHP systems are the next-lowest-cost solution, but those instances are pretty rare in the northeastern US, and even when you're at break-even, a ton of lowered load from envelope improvements usually has a longer life-cycle and fewer maintenance issues than a ton of geothermal.
[end soabox rant]
OK, enough thread-drift- back to the Geothermal Nightmare. :-)
In my experience with regular mini splits, when a drain is clogged, they pour water on the floor. It is unlikely in my opinion that this is a clogged drain issue. Rather, what is being seen is very humid air drawn over a low temperature coil, creating fog, droplets of which land on your hand when put in front of it. I believe most of the problems will be solved when the coldest possible water is run through the units. Anyone who has run a hand me down window ac for 10years without looking at it and seen the frost on the evaporator knows that standard ac runs well below freezing internally in order to do its job. The high airflow and relative inefficiency of thermal transfer to the outside prevents frost from forming normally. If the inside loops need antifreeze to function, so be it.
50 degree water translates into a fin temperature of what? Too high to dehumidify by the evidence.
At some point someone is going to come up and post some actual math proving what I just posted, but i am simply too lazy to bother figuring out how many gph of 50 degree water it takes to deliver 3 tons or so of cooling. I estimate a billion.
Close enough
Keith: Mini splits often run coil temps close to freezing, with very high latent cooling compared to chilled water coils. Since there hasn't been a real sensible cooling load since the water temps were reduced, and the outdoor dew points in central NY have dropped back into the 40s for the week, it remains to be seen if in fact it won't be pouring water on the floor once the muggier air and higher outdoor temps return.
And those conditions will return, at which point we're likely to find out whether the drains are running free or not. With 56F water there's just way to know for sure, but it's doubtful you'd be getting much in the way of fog with 56F water at the temps & humidities indicated by the AcuRites in Colleen's pictures.
Speaking of anti-freeze, I'm wondering how the line sets routed on the exterior of the house will fare in a central NY winter without it. But WITH antifreeze, the heat transfer at the coils would be measurably lower than with water-only.
I'm still mystified by the wayward droplets, but that doesn't stop me from yet more hypothesizing:
1) Really high air flows across coil fins can entrain condensed water droplets
2) If the condensate drains are blocked or inappropriately sloped, I wonder if it is possible for some designs of fan coil for the fan blade tips or ring to pick up some of the puddled water and toss it into the air flow. Window shaker AC units now incorporate a slinger ring to deliberately do this, both reducing nuisance drips and increasing heat transfer / efficiency of condenser coil. Not a good move for an indoor fan, but a distant possibility?
3) Fog formation, IMO, requires mixing air with very high delta-T, such as when 0*F air falls out of an upright freezer compartment into a humid 70*F room. I've seen car ACs do this for a few seconds upon startup on very humid days, but car ACs routinely manage airside delta-T of 30-50*F, roughly double residential systems. I doubt that is happening here.
I like the possibility that water flow to air coils is / was blocked by air in the water lines.
I agree that a blocked drain is more likely to show up as water leaking from unit and down wall
I agree that it will likely require chilled water temps in the low-mid 40s to provide an air side delta-T around 20*F, which in turn is typically what is required for dehu anywhere other than the arid west.
Curt, Dana, Sal & Keith - I'm enjoying learning from your posts as we wait for the return of temps/humidity to see if our system has been fixed or not. The HVAC specialist did not come this week as we expected. No word. Assuming they too are waiting to see.
Dana - enjoyed your rant although I did not understand some of it. I just wanted to add that 1. we do have antifreeze in the lines and a lot of it as our geo-field floated this winter. (I told you this AC issue was only one facet of the problems here.) 2. Yes - every time they have come they have purged more air from our system. There was talk of putting an automatic air-flow valve/vent (AAFV) at the top of each of the fan-coil units, but there is no room to do so. So we have a typical spiral valve on top of the 80 gal. tank along with an AAFV. That was added this past Jan/Feb so our installer who was just here is hoping that the purging he just did may be the last of any air caught in the system and this will not be an issue anymore.
<>
Dana - I find this the most interesting of what you said because I think we have done the things you mentioned first - new E-efficient windows, the house is wrapped under the cedar shakes and the blower test showed we are very tight. The only alternatives we thought we had to choose from were a coal/pellet furnace, Geo, Wind or Solar. Any chance you would elaborate on this?
Colleen, sorry for this further OT comment... Dana, I'm am absolutely wowed by your contributions to this forum. I imagine you sitting in front of an array of screens pulling up data from all kinds of sources. They should give your comments an Advisor's grey box.
No apologies needed, TJ - I totally agree!
Colleen: I have no prior insight into the particulars of what other measures of what you had/hadn't done in terms of lowering your heating & cooling loads. It's simply been my observation that few people with GSHP systems fully did the math on the cost effectiveness of different measures relative to the reduced geo sizing &/or the other alternatives.
Out of curiosity, have you done any blower-door + infra-red imaging directed air sealing on the place (usually one of the most cost effective strategies to start with)? And what were your cfm/50 numbers on the last blower test? Is there any foundation insulation? An uninsulated CMU or concrete foundation in an otherwise decently insulated house will usually hit double-digit percentages of the whole-house heat load, even when there's insulation between the basement ceiling/first floor joists.
In some ways it's a case of competing subsidies, (including net-metering details), and requires reasonable site conditions but I've run the numbers on a few representative projects where a combination of building envelope upgrades, photovoltaic solar, and going with ductless air source heat pumps was more cost effective than geothermal. Though a well designed geo system will be somewhat more efficient than mini-splits in a northeast climate, the difference in annual power use can often be more than made up by spending the difference in installation cost on PV. It's not a simple calculation to make, since the subsidies are volatile and change from year to year, and the power metering/compensation deals vary by utility and state, so I don't fault people for not being able to chase it to the last penny, and the picture can change even between the time the decisions get made and when they're implemented. Even the heating & cooling loads are often not correctly calculated, leading to somewhat oversized (and more expensive) systems. It's one thing to just ballpark it when installing a $3-4K condensing gas furnace, quite another when looking at $3-40K of GSHP. I assume the contractor submitted a heat load calculation, but did you get multiple calculations from different bidders? The range of load calculations from contractors is often pretty astounding.
GSHP systems run about $9K/ton (before subsidy) on average for 3-6 ton systems in my area. (See: http://www.ctcleanenergy.com/YourHome/GeothermalIncentiveProgramResidential/tabid/520/Default.aspx ) Yours being a pond-loop may have been somewhat cheaper since there wasn't much drilling or digging involved. PV is running about $4000/kilowatt (pre-subsidy). Most mid-sized homes can be heated/cooled with less than $10K of ductless, which in your case leaves over 20 grand of cost-difference- enough to buy 5kw of PV at current PV costs, which (given reasonable shading factors) would yield 6000-6500 kwh/annum in a central NY location, which buys back a lot in the way of efficiency differences. Whether the numbers would actually fall on the side of PV + ductless in your case isn't clear, and entirely moot, since you already bit the bullet on the GSHP, but it's a calculation I strongly recommend people to make before diving in, especially now that PV costs have crashed to unprecedented lows, with some room still to go. (In Germany ~5kw rooftop systems are currently running under $2500/kilowatt, installed, and it's not because German labor is cheaper, and it's the same hardware.)
State/local/federal subsidies are in a constant state of flux, but PV prices fall year over year. It may be worth keeping and updating a spreadsheet on the net-present value of adding grid-tied PV, if you have reasonable solar exposure- at some point in the next decade it may become a compelling investment. That's what 100s of thousands of German households have calculated, but their feed-in tariff subsidy and streamlined permitting & lower costs combined with higher retail electricity price make it a much simpler calc, and a bit more compelling.
http://www.greentechmedia.com/articles/read/why-germanys-solar-is-distributed?utm_source=Daily&utm_medium=Headline&utm_campaign=GTMDaily
Hopefully your air-purging days on the water loops are over. The bubbles of air tend to collect at high points on system, and you can never get all of the dissolved air fully purged in the first round (which is why vents/scoops/traps are standard), but once you're there, your there. Every time you crack open the system for repairs or updates it's back to square one, but once you know the movie and the symptoms you know where and how to deal with it.
So, lots of us just reading this thread and shaking our heads I bet.
Thoughts.
#1, if this system is truly not functioning, all parties to the situation are the problem. These systems can be installed and can function properly.
I don't buy much of what has been posted. There are truly geo installers that can install functioning systems. If this one is not functioning properly,
Lastly, I am a firm believer in the fact that most homes should not ever have a geo system in upstate NY where I live. Unless the home is huge. Small homes well insulated need to follow the thinking of Dana Dorsett.
Collleen, the air problem in your lines at this point to me should never of happened and should be done with period.
&34,000 to buy air in your geo lines and water droplets spitting at you is just fundamentally not something a 30 year expert contractor should be selling.
Get a real expert in and send the bill to your present expert.
IMHO....
keep up this thread, love to hear of the happy ending.
Oh and what have your monthly HVAC bills been now? Hopefully at least that part of this is going well....
Dana - I understand what you are saying! We do not have the results of the blower test - that went to NYSERDA, I believe, as we never got anything, so I can only report what the fellow doing the test said when he was here.
We had 2 companies bid our job as that was all I could find that seemed like companies who had experience. The one we chose was also recommended by a friend nearby who they installed a ground-loop at their 1800's farmhouse and they are truly happy with it. They are on air-handlers only - no fan-coil units like we have. We are thankful we chose them, even with all the problems, as the other company (over 10 years installing Geo) went bankrupt and has 9+ lawsuits filed against them. BOTH gave us numbers in terms of the system paying for itself - 7 for heating, 11- 12 years when adding cooling.
We discussed the possibilities of PV for a few years before this as we are set up on a SW exposure, but we have huge trees around our home which are on the neighbor's property and the roof it would go on we can not reach in the river because we're on a hill. With the snow-load we get here just north of Syracuse, NY, we would have to be able to clear them in the winter in order to gain true benefit. We never had anyone out because that seemed to stop us. Perhaps we were wrong in that assumption? We also talked about and researched Wind. I have 2 years worth of wind data from a weather station. Although our area is rated I believe a 2, I think we get a 3 rating right here because we are on the bend of the river, so we almost always have a breeze of some kind. Just north of us a couple miles is the Tug Hill Plateau and they definitely can utilize wind. We are not zoned for a tower but I was looking at the drum style ones and still have this in mind as prices come down (hopefully) to help offset our rise in electric from the Geo. I look forward to reading the 2 websites you link to here. And I TRULY hope that prices start to come down on all of this greener technology to help make it not only better but more affordable for the masses. Something has to give in America and hopefully it will be soon.
AJ - thank you for joining this discussion! Back when we began this, it was HARD to find a so-called expert. I looked for companies who had been in business for 10+ years because we found a ton who were in business only a few years. I can tell you our contractor has never had a complaint filed with the BBB and there is nothing disparaging about them "at all" on the internet. Considering these things, we figured this was as expert as we could get. But alas, this system has not functioned properly. The problems you see here are just for AC. We had problems all winter causing us to rely on 3/4 of a tank of oil running our original (and only 7 year old Energy Efficient oil burner) for our baseboard and in-floor radiant - hence the title of this thread. So we will have to wait until this is all sorted out and winter comes again before we can see the savings. Our friends who have the ground-loop system here near us are thrilled with their energy savings, so it's our hope that when all is said and done, we will be too.
Colleen - can you confirm/clarify the following?
1. per your comments in #4 and #29, the fan coil unit was 'spitting water' _last_ year, but hasn't this year? (my ? in #32) - that is, it hasn't been a problem since turning down the fan speeds.
2. per your photos in #21, the lines in the exterior 'chase' are only condensate drain lines, not chilled water lines right? so the insulation levels aren't super critical.
3. do the condensate drain lines have p-traps, to keep air and bugs from moving in/out? (#18_6) Probably not a big issue; but without a trap, air flow over the drain hole in the drip pan and/or whole-house pressure differentials could draw warm air up these drain pipes, where it might _cool_, but also could pick up humidity.
Sounds like air in the system was blocking the flow of chilled water (#18_4); [ and/or too slow pump ] ...wish I had been smart enough to think of what could be blocking it! ;) Just for reference, could you tell us which of the 3 fan coil units' chilled water lines air was drawn out of, based on the locations and in/out temps you gave us in #21_5? Also, any idea which pump was set at low? Sounds like it was delivering chilled water to one of the heads, but which one would be nice to know.
Sorry to say this, but a lot of us are probably hoping for the hot, muggy weather to return... ;)
forgot to add:
Colleen: Interested to know more about your 'floating geo field'... >.< and what % anti-freeze, what type, when added, and how this compares to your friend's 'trouble free' system?
Dana: Interested to know more about reduction in heat transfer due to anti-freeze...
Colleen wrote:" BOTH gave us numbers in terms of the system paying for itself - 7 for heating, 11- 12 years when adding cooling."
Interesting... are you saying that Both contractors did a comprehensive Energy Audit of your home?
Or did they have access to the complete NYSDERA Audit?
Or did they merely use the "Savings Calculator" at the contractor's website?
http://www.vanheegeothermal.com/
Enter your address and Viola.... A "fly by" Audit ....
With savings calculated to the penny!
I noticed that I could SAVE $909.59/year on my cooling bill alone.
Pretty amazing since I currently pay about $200/year.
John,
Thanks! Great post.
I too ran the 'calculate your savings' link on the website John linked to. Amazingly, though I didn't do quite as well as John, I could apparently save $1055.75 a year on the roughly $700 a year it costs to heat and cool my 56-year-old house and 12-year-old studio. Does that mean Duke Energy will be writing me a check?
Dana - in reply to your questions in #53 & 54
1. Correct - the fan-coil unit in the loft (pictured above w/AccuRite) is the one that spit water onto our hands last year. It has not done it this year in either time we tried to run them for AC
2. The exterior chases pictured house both condensate and water lines and are heavily insulated. See ? #40, 2nd to last paragraph.
3. The installer could not remember if there is a p-trap in the chase or not. He didn't believe so. Said we can tell because if there is not, when it's running we will feel air blow out of them. It's been too cold here to give that a try.
4. He got air out of 3 of the 4 units. The one without air was the loft unit, pictured above.
5. I believe the low set pump was to the LR, but I'm not 100% sure on that.
6. The floating geo-field. UGH! When they came to dig the trench to the river and sink the field, I asked if it would be alright to put mirafy (construction grade breathable landscape fabric over the top of it to help act as a weed barrier as we are getting overgrown. They discussed it and said yes, so I went out and bought some. The guys wrapped the field which is now believed to be a problem and I'll attach a pic here. FYI - we are getting ready to dive down soon to cut it away.) This work was done February 6, 2012. I'm attaching pics. They were out because the house was not getting warm and nothing was happening with the fan-coil units, then we found FP flashing on the Water Furnace - Freeze Protection. They came out and worked on the system, got air out of the lines and added more antifreeze to the geo-field loop. The next morning the field was floating but the house was warm. They came back a week later and the field sank the day before they arrived. I honestly can't remember what was done indoors, but they worked on the system for a few hours. It seems that when we would run the floors, the fan-coil units would air-lock. We had two whole zones not working at one point. It was just continual. And our Oil Boiler was called upon because we were cold, but the boiler, which has always given us all we ever needed in heat was NOT keeping the house warm either! Then the field floated again a month after the first time (Dec 29 and Jan 31). It sank the day before they arrived a week later. The system was worked on again, more air, new pumps in a few places, the boiler was left on another 24 hours until the house warmed up, then we were able to shut it down and I don't believe we needed to use it the rest of winter. However I did notice and finally mentioned that I never heard the Water Furnace shut off at that place where it comes into the house from outside. (there's a pic in the 1st batch of that equipment). And I was freaking out about our National Grid bill which was off the charts. Our contractor said the system should be shutting off and our bill should be only about $200 or so a month in the winter with the Geo, based on their other clients and their own places - things our size. Now they feel that the mirafy over the geo-field is a problem because it doesn't allow the water to flow past and through it, so it iced up (which we can't figure out since it's 10' down, at least. BUT they will be really happy when it sinks into the river-bed... which to us means, no water is flowing through it! They also feel that their salesman must not have known that our in-floor radiant was not put in with the ceramic plates to clip the pecks up to the sub-floor as is required in Geo, even though we sat here and explained to both companies about our in-floor radiant (in part of the house only) because WE installed it. So they are feeling it is too cold in the crawl space and that little flex in the lines is why it's not heating adequately and is continually calling for heat.
Our friends have a loop in their pasture off their home.
I truly apologize to all for the lengthy replies - I do not know how to give the info I think you are looking for in a more abbreviated way.
Sorry for the duplicate - deleted and full reply posted below.
Hi James & John - thank you for your questions. No, we did not use a calculator such as seen on the website mentioned. Both salesmen who came here took info from our past year or two worth of utility bills including the current price of oil that day, they counted and measured all of our windows and doors, asked about the age of and wrap of the house, insulation, measured the house, both basements and both crawl spaces (from our survey) and then they came back with a cost/savings ratio for us. Interestingly enough, they both said we would only need about 8-12 gallons of fuel oil a year to back up the Geo as based upon weather data for our area from the past 20 years.
I can tell you our bill for Fuel Oil was: 2010 season $2029, 2011 was $2760 (and was projected to be $4000 for 2012 from our fuel oil carrier).
The NYSERDA audit was not done until we had chosen a contractor and signed a contract.
Colleen, don't worry about the lengthy replies, they are appreciated. The main problem we have here is that people will post interesting problems, we get part way through discussing them, and then they never come back with follow-up information. Better that we get all the way to a conclusion.
Thanks David.
I am just reporting that we are still cold and rainy here. I will let you all know what happens when the weather decides to become more summer-like again.
It has been 2 years since I posted here last and I'm sorry to say that our system went from really bad, to worse, then back to pretty bad. After multiple requests to our contractor to bring in an outside expert to which we were told "we ARE the experts", then having to ask if we needed to get a lawyer when they said they couldn't take this out and give us our $ back, they did bring in an HVAC Geo Expert they are friends with. This happened in Spring 2014. John took utility bills for multiple years, suggested changes in the house to the system, had sensors put on at multiple places, then went out side. He told me that the worst place for a Geo system is in the river and that if 800' worth of vertical wells were put in, our system would work like a rock-star. There was a question as to where those vertical wells could be put IF they were to be used. Our report stated that as the system was (before changes) it was costing us more than Fuel Oil alone. If his stated changes were made, it would increase our efficiency by 7%. (Still no where near where we were told it would be when sold our system) He left saying, "We'll collect more data now and see what it tells us." John has not been back. The humidity in the house while AC is on has gone down to 60% (not the 48-52% we had before Geo, but were told we would get). In order to achieve this the house has to be 64-66º and we can only run certain wall units (splits) or the Air Handler in a certain combo or the system doesn't take out any humidity. Last winter, as soon as it got cold (mid-Nov) the oil boiler had to be used as back-up - it ran the whole winter. The Geo could not warm the house & the water coming in from the river was, for the 2nd winter, at 17º. We went through 450+ gallons of fuel oil. Because of this, we have had no other option but to seek legal help as our Contractor says there is nothing they can do. We now need to see an Expert Witness in GeoThermal. I'm sorry for this long absence and long post, but I had hoped things would be fixed and we would have the system we expected. Can anyone recommend a GeoThermal Expert Witness that we can hire to look at this system and give testimony? Thanks so much. I can answer any questions anyone has.
Colleen,
I don't have the name of a heat-pump expert who can help you, but I wish you the best of luck.
I have just re-read some of these posts. Your example is a cautionary tale for anyone considering the installation of a ground-source heat pump or a water-source heat pump. Assembling a one-off site-built HVAC system from a variety of parts is always risky.
Colleen ,
You may contact me and I can give you the names of the folks you need to testify and fix this thing if that is possible . If a man built it a man can fix it , but at what cost . One thing Martin and I will always agree on is that design and commissioning is key and are rarely free or cheap .
[email protected] . 732-581-3833
As I read through I was on the edge of my seat to see the solution. Only at the last two Answers from Martin did I realize the posts were two years old! These poor people really have been through the grinder. Lessons learned for everyone? Maybe "simple and sufficient" is the motto. If they had to do it over? How about no radiant in floor, no ground source heat pump, no mini splits, just good insulation and 8kw PV and electric resistance heat and regular air con.
Since they have the in floor radiant they could cool straight from the river and just run a de humidifier and forget the air con. Cooling with in floor radiant works well in dry hot climates, but should work fine with a dehumidifier on the East Coast.
Ven is quite correct . Monitoring RH and mixing the water to 3* above dewpoint will absolutely handle sensible load , lateht can then be done with a dehumidifier . Abandoning the system now would make this tragedy worse than it is at present .
It is a shame that more contractors , many more , are not properly trained in The laws of thermodynamics and building science so they could provide proper systems . When will the industries come together and quit bickering ? Until HVAC contractors learn their trade from someoine other than manufacturer's Reps we will continue to do the same things wrong .
I'm sorry you didn't get enough help here to fix the problem, and are on to litigation. I wasn't active here when your query first came around, and you have certainly piqued my curiosity as to how to get the system running better. If you have data from the monitoring that was put in, I'd be interested to take a look. Things like water flow rate and temperatures on both sides of the loop, the model of the heat pump so we can compare conditions you are running to its specs ...
I'm suspicious that the coils in the river are simply too tightly clustered, and they start to ice up, and then once they are iced up, the thermal resistance out to the flowing water goes way up.
It seems as though GeoThermal units are always a high-maintenance problem. I can't see how they would outperform ductless mini's that go for $2,500 per install. Spending $35,000 on a geothermal system that needs constant repairs and upkeep does not make sense.
Everyone, thank you so much for your responses. Charlie Sullivan, I don't know how to gather that data but if you know a way, we will get it for you. You are the 1st to mention perhaps it is the coils too tightly wrapped. Because we were told last year the river is the worst place for the field, I wonder is it because we are in a constantly moving river-current which does not freeze over all winter, unlike a pond or lake?
As we stand today, the company who has maintained our boiler system but has no GeoThermal expertise is sending out their most Sr estimator to look at our system and give us a price on disconnecting it, to put us back the way we were, which would mean going back to regular AC units - which also would mean holding up siding installation that was due to start 8/11/15.
Richard McGrath, I will be calling you and truly appreciate your help.
If you all would like, I will continue to update here with the rest of this very sad, disheartening, expensive-beyond-our-comprehension saga.
Colleen,
I came across this discussion today. As an owner of a geo system (in central NY) that was affordable, and works great, I hate to see it when people get systems done that don't work or work poorly. It just sours people to a heating technology that can really work well.
I put a post on a geo forum that is frequented by some very competent installers, on your behalf. There has already been one reply. Here is the link. I hope you can get some help there with your system.
The link I just tried to add to the post triggered the GBA spam filter. Anyhow navigate to the Geoexchange forum. Go to the maintenance and troubleshooting forum. Title of my post is "Geo system issues (not mine)". There is already one offer to look at your system by a Waterfunace Geopro dealer at no charge.
[Editor's note: Here is the link: https://www.geoexchange.org/forum/threads/geo-system-issues-not-mine.6509/ ]
In a pond or lake, the temperature at the bottom tends not to get below about 40 F, because water any colder than that is less dense and rises to the surface. The coil sitting there will cool the water next to it, which will rise, and get replace by more 40 F water. So the 40 F water is replenished by natural convection.
In a river, the water can churn a lot more and you can approach 32 F throughout. That lowers the efficiency because you are working from a lower temperature, but I think the more severe impact is that you are closer to freezing temperature, and you can more easily ice up the coil. Ideally the flow of the river would be sufficient to move the water through before it freezes, but it would seem that you'd want the coils loosely packed to improve your chances there.
A google image search for "pond geothermal" reveals that your loop is a lot more densely packed than many. There are widely spread versions like this:
http://geothermhvac.com/wp-content/uploads/2012/03/Pond-Loop-2.jpg
or loosely coiled version like this:
http://prostar-mechanical.com/heatpump/geopics/geo/pond_loop4.jpg
There's also a company that makes clips to space them apart:
http://www.geopondclips.com/
I tend to think that the wide spread version would be the best bet in your situation, although I can certainly understand your reluctance to continue experimenting and preference to revert to your original system.
As for finding a way to provide the data you have, what form do you have it in? The options for file attachments here include a lot of formats ...
Sounds to me like a clogged condensate drain. Except sensors should be shutting down your unit if they are clogged. all that means is the cold coil (evaporator), like a glass of ice has water dripping onto a coaster, has water dripping into a pan which has a drain pipe. That drain pipe gets clogged. Blow it out with an air compressor or suck it out with a shop vac. Changing your air filters and using quality ones reduces the amount of dust and dirt going down that drain pipe. If your unit is humidifying beyond putting the same water back into the air that it took out then it is both heating instead of cooling and is leaking lake water from the geo loop into the unit.
Another offer to help from over at Geoexchange from my post there.
Colleen,
could you please contact me at [email protected].
I am one of the board members of the NY Geothermal Association, and we are seeking quality assurance for geothermal systems in NYS. I am also a Certified Geoexchange Designer and Installer.
I stepped over your Scott Smith's thread on the geoexchange forum yesterday, and would like to get to the bottom of this.
I read through this thread here, many opinions, but not much informations on why the system does not perform to your satisfaction.
This morning I communicated with the representative of the heat pump manufacturer, the owner of the company who designed and installed your system (and modified it in 2014), the geothermal expert (John) who came in in 2013 and evaluated your system (who is also a board member of the NY geo association, a mechanical engineer, and one of the most knowledgable people about geothermal I know). I also have a phone calls into the sales person (who is not with the company anymore) who sold you the system, provided the estimate and designed your system.
Right now I am trying to find out the facts and again, would appreciate if you could email me with your contact info, so we can get to the facts.
Thanks
Hi everyone - I am going to answer/comment to everyone in this one reply to help keep things simple..
.
Scott Smith, I have gone to GeoExchange as you suggested and have posted there as well as emailed Mr Jenser. Thank you for your help, advice and proof that a geo system in CNY really can work properly!
Charlie Sullivan - thanks for the explanation of perhaps our coils being too tight. Compared to the pics (links) you have provided, it is easy to see the difference. I do not recall seeing any Gator Clips on our coils and none show in photos I took at the time. When the "expert" was brought in by our contractor last April, he advised on multiple changes to be done inside the house first - then said, "and we'll collect the data from all of this next year and see what it says." So I don't know exactly what was done, but we are happy to look for whatever you may need to gain more data, if you wish. I can email you the pdf of the report done last April, too.
Todd Conradson - you are correct in that the tubes were clogged which is what caused 3 of 4 MultiAqua mini splits to leak down the walls & thru the ceiling. We were never advised to clean out a drain tube but I have been faithful in cleaning the filters every month they are used. They are reusable filters which MultiAqua sent with the units. The water sitting in the pan only to be blown back into the house appears to be the humidity issue has been slightly fixed. Whatever the techs did last Spring has brought the humidity down in the house from 78-80% to abt 60% - which is still too high yet the house will be 64ª which is way too cold.
Mr Jenser, I have emailed you our contact info and replied briefly on the other site. We appreciate your help. Thank you very much for the calls and investigating you have and are making on our behalf. If there is an easier way to share the facts of this case to you, we will gladly do all we can to accommodate your request.
Again, THANK YOU everyone!
Hello, Colleen. I am brand new to this community and have read with interest (and much sympathy) your trials with your geothermal hvac system. Have you had any resolution to your problem? If so, can you tell us how it was resolved? Or have you chucked the system altogether?
Thanks, Colleen.
As we close out 2015 tonight, we still await some kind of resolution for our GeoThermal system that has never worked properly since it's install nearly 4 years ago (March 2012). Chris & Martin from NEGeo were very helpful and supportive but 1. we are out of their territory & 2. I've not been able to get back in touch with them. Chris even called Water Furnace on our behalf and we were supposed to receive a call from WF but it never came. We have been blessed with a warm winter so far, but in Upstate NY we know this won't last. Our lawsuit allows us to have the system evaluated by a certified GeoThermal Designer of our choosing and the work performed by someone of our choosing, or the system removed and us put back the way we were. Any helpful advice will be greatly appreciated.
I think it would be sad to entirely rip it out--I'd rather see a certified designer fix it up. But it seems like it's really hard to find someone to do that. I guess all I can really suggest is that if you have proposals you'd like to have independently evaluated, you could post them here.
Thank you Charlie - I will do just that.
Thought I'd take a few pictures this morning of our system readings for everyone here... the temps have dropped here in the NE so we have had to turn on our boiler for backup. Keep in mind that the Water Furnace still runs continuously WHILE the boiler is running, causing our electric bill to remain super high. As I write this, it is 9ºF outside at 7:40am ET. If anyone has any advice, please feel free to share.