Heating with modulating condensing units
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So far my looking into the use of a modulating condensing unit has left me with
the following;
They are high tech
They cost more than some older tech
They need good water with proper hardness and PH
They need a tech that is trained to maintain them
They do not condense if the return water is above 125 degrees.
Many install set ups include primary, secondary and what I call tertiary loops which to me add cost.
I can’t understand how we go from $1000 to heat water to $8000 for all the parts for a fairly basic
boiler room set up and that does not include the heat emitters in the rooms.
This thread is about hydronic heat with fuels. I have some homes where mini splits are not an option for primary heat.
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So far to really get the cost and maintenance under control it looks like
HTP Phoenix modcon water heater piped properly for safety via and open loop system with infloor or in wall or in ceiling PEX.
Far more expensive but liked would be to use radiant wall panels sized large enough for low return water temps and add a heat exchanger to separate the water, closed system. This system materials go up substantially adding a several thousand but a bit less labor.
Interested in actual installed systems that work well that are simple and lowest cost. I hope some of you post pictures of your hydronics wall and all. I can post some of one I built decades ago as a newbie to hydronics.
One note of safety, pressure and temperature relief valves need to be operated annually as per instructions, they can stick as I have had happen. Customers that do not get annual servicing need to know that there are reasons to service even though nothing is going wrong with a system. secondary high limits, low water shut offs, low water pressure shut offs all are good things to have.
My boiler choice right now is a modcon water heater.
They don't short cycle, and they condense easily and they can provide domestic hot water at low flow rates and no cold water sandwich.
HTP phoenix and some others fit the bill with stainless steel tanks for longevity.
The phoenix is priced right at $2,000
Condensing units have very low cost flues, PVC pipe, and easy low cost labor to install.
Set back control is available,
Seems like the best chance at getting close to the 95% AFUE rating since many install of mod cons in old 180 degree systems will not perform as they should.
Be nice to pipe in just one circulator, direct to zone valves using an ECM circulator that is variable speed to deal with changes in loop flow rates.
Where is John Barba (expert hydronics adviser) when you need him....
Richard McGrath... if you have any similar installs lets see them posted.
AJ,
Pretty large house so there are several remote manifold locations . System has been on roughly 1 year and gas bills have been 738.00 . Young builder trying to learn about EE houses . He is now understanding that the architect is not the guy to listen to and that the trades need to meet and discuss before it goes to a table to be drawn .
Yes this system has 6 pumps , at design they use a total of 118 watts , so far they have averaged about 60 watts , have not reached design as of yet . average SWTs are 100* F , this one condenses ALL THE TIME . These radiant floors are responsive to setback due to the Graphite coating and tubing directly below the hardwood .
Solar thermal panels and 535 gallon , 8" insulated wall Coccoon tank will be installed this spring . We expect that after these are installed this customer will pay the utility 112.00 per year including meter charge . The Versa Hydro is solar ready and Energy Star rated as such .
http://mechanical-hub.com/langans
Richard, that system is impressive. A 7267sqft home can afford that system and it should.
Right now i am working on building systems for 1000-2000 sqft homes and keep the costs under control too...
Any examples of small systems with one or two pumps?
Here is one of the pics from Richard's hydronic wall
State of the art with Delta T circulator and more.
AJ,
The phrase you are looking for is "modulating condensing boiler," not "moderating condensing boiler."
The words you chose describe a web editor, not a boiler. It seems to me that I am always moderating and condensing.
Can words truly describe a web editor?
I'll try... patient beyond the call of duty...
Thanks Martin for moderating my modulating...
Richard: where is this 7000sqft+ house located?
JIn, read the link, Spring Lake, NJ. We have homes that size and much larger on the lakes up here. The turn of the century great homes were divided up later in the 20th century but now with all is going in reverse as property taxes are rising to $15,000 to $50,000 on the lakes and more.
I was asked to bid on a minor system redo for a remodel on the lake, the price ballpark was going to be $200,000 plus for the HVAC modifications... I gave the project away to the best in the area. The boiler room was like stepping into the basement of a hospital.
Which is pretty ridiculous ...
50 000$ in taxes..mouahahah
I sometimes wonder how humans have manage to survive this far in time
while being so ridiculously stupid.
Anyhow, ~5500HDD location and only 740$ for heating a 7000sqft home.
Richard you will need to provide maths for that, very intriguing!!
Jin, when the bank account adds a few million weekly, folks spend a bit more than I and maybe you do. Not ridiculous when you have that much income. And their lake home is their small cabin away from their main home at 100,000 sqft and who knows the taxes...
adds a few million weekly ..ahahhaha
let's stick to topic will ya! :)p
Looking again at the following link on Richard's work ..
http://mechanical-hub.com/langans
I hope that those "mansions" feature external basement insulation ...
cause i do not see any from the interior side!
Jin,
Not that it matters but that basement stays 71* without any conditioning . That is the way I designed it and that is exactly what happened . That slab charged one time at start up . The piping losses thankfully through sheer luck are exactly what the basement requires at design and since There are no windows and 80% of the exterior walls are 12' inside excavated footings that hold up the 12' verandas and yes all of the exterior walls are insulated to the outside . In addition to that this homes footings are 6' above water table due to it's elevation on site . You may also notice that supply and return piping is not insulated , this was also done intentionally since to keep install costs down . I will explain , this house was done with 1 Supply water temp as most of my designs are done . This is why the basement zone has never called after initial charge of the 3,396 s.f. x 4" slab .
One room drives the SWts , that would be the room with the highest required average water temp at design . This home has 22 zones of radiant and you'd be hard pressed to find a .5 degree variation between areas at any time . This type of zoning also really goes a long way toward avoiding overheated rooms due to SHG . Floors cannot overheat since when the required surface temp is reached the zone satisfies and flow ceases . Too many people worry about hardwood floors when if you have a clue it is unnecessary to worry about such things , also due to these higher than needed temps no energy is wasted and it is very fast to respond to set back . Hardwood usually has issues due to moisture and that has been taken care of in this home also , Rh is a nice 60% all year long , and the indoor temp during summer months is 74* because the A/C ducting and equipment was sized properly , balanced ventilation and all .
I always do the math my friend . I have been doing this for quite a long time without advertising , business cards , none of it . People call me to fix what others screw up . I will do better than show maths my good man . In March when a complete year is up I will post utility bills . No math states anything better than actual data , wouldn't you agree ?
This system will only use the energy required to heat it and do DHW at any time , best thing about this system is the fact that if we ever get below design the system will handily respond and keep my customer comfortable with ease down to -20* although the electrical usage will increase due to flowing more water at those times .
All that and an engineered plumbing system for 12.25 per square foot , not too bad considering it is a 5 bath home with every extra you could have damn near .
AJ ,
you'd be amazed at what can be done in a smaller home . You have my number .
Richard: what do you mean it goes itself...
do you mean that it is heated from solar thermal panel since day one ?
60%RH ??mm ok
You know you sound like an add for yourself right ? :p
For the non initiated such as myself,
could you please explain what is going on here.
Is this house solar + gaz + electric heated?
What is going on here is a rather large home is being provided space heating and hot water at a rate that no other technology can reach . PERIOD . It is being done with NG . No solar panels as of yet as stated in my comment . I just re read that and my other comments and cannot figure out what you mean by " it goes itself" , it is pretty early though , maybe I missed it . What part of " Solar panels , tank will or should be installed this spring " are you having trouble with ? This customer is now thinking of combi panels in case you are interested , you should check into them , they really are quite a nice technology and since the solar thermal is integrated makes using that also a little less hard to justify . As if any FREE amount of useable ENERGY should have to be justified on a site where GREEN is in the name .
Jin , maybe where you are from it is common practice to ask someone for detailed explanations then when they give it to sound insulting (" you know you sound like an ad for yourself right ") . If trying to share some of the methods I employ to make these systems work properly and how others can avoid some common mistakes and strategies , OK . Most would find it offensive , I do .
60% RH . Sounds like you have a problem with that ? Oh well , others do not . Maybe you should thoroughly read the link supplied by yourself , I believe in AJ's last discussion . I believe you will find 60% within that document . I honestly do not know how anyone else designs homes , I design them for the occupants who pay me and their desired comfort . This does not mean I will do anything that would cause problems within however .
I am guessing you are one of those guys who reads everything just far enough through to support your viewpoint then stops as if there is no further text . Maybe you're an inspector .
http://www.buildingscience.com/documents/bareports/ba-1405-draft-climate-specific-passive-building-standards/view?searchterm=passive%20house
For all who are truly interested in being part of the team who will lead the industries into a Better built environment .
http://www.healthyheating.com/Integrated-Building-HVAC-Design-Course.htm#.VJA143uUKdk
Richard,
You wrote, "As if any FREE amount of useable ENERGY should have to be justified on a site where GREEN is in the name."
GBA has always evaluated, and will continue to evaluate, renewable energy equipment based on several criteria, including the following:
1. Is the investment in the equipment cost-effective compared to other alternatives?
2. Will the equipment produce, over its expected lifetime, enough useable energy to justify the embodied energy required to manufacture the equipment?
Equipment isn't free. Solar thermal collectors require copper, for example. Copper mines come with a heavy environmental toll, and copper mining is a dangerous job. That doesn't mean that we shouldn't use copper; it just means that copper isn't free. It isn't free from an economic perspective; nor is it free from an environmental perspective.
A luxury home that is 7,000 sqft needs someone like Richard and his HVAC set up. Why? Look, a home like that is not the place to install twenty mini splits to start with, and to end with IMO.
The other factor is, choice. Like I have said and Richard we go over choices with customers and they choose what they want for what their needs are. Not GBA's or Martin's or Jin's or even global warming.
But, I bet Richard cares as much as all of you and I do. We care about the planet. All of us are living here and moving in the right direction. How green am I? I have done the one single most productive thing a person can do and many of my friends have, which is to have less offspring. Those missing folks from the planet produce 0 pollution.
0
Jin, please be nice. Richard is a great source of info as to do with hydronic heat. For those that have hydronics we need Richard. If you don't have interest in it and prefer some other source, then be nice and if here see what you can learn. I am here to learn, hydronics have their place for me anyway. I also would love to start installing mini splits, I like PGH, I like PH without the plaque...as you know I do not think much of OSB.
Jin, 60 RH is relative humidity. Richard is saying the basement is getting "free" conditioning and that he planned it that way. I have done the same.
Martin and others ,
I do not disagree with everything you believe or think . There are many ways to do similar things towards similar ends . At the end of the day the consumer will decide what he wants . There is more than one way to collect and store energy for use as you need it . They don't all require a manufactured panel , or an expensive tank . or a closed / open loop GSHX .
Ypou do realize that the equipment you tout contains refrigerant . This si far from friendly and farther from Green . Environmentally friendly does not mean environmentally friendly .
We throw away garbage that makes energy , some companies are now using it . We are surrounded by water that contains energy , some use it . The sun comes up everyday and gives us energy , use it , that same sun gives energy that is not being used . Solar Pv panels heat up and lose efficiency , why not collect that , keep the electricity flowing batter and use the waste for another purpose . the fact that you are getting that power for free does not mean you should waste it when there is more there for the taking .
Mechanical solutions are not the end all be all in this fight . Stop reading what others write and do your own work . You'll be amazed at what can come right out of your head .
A relative humidity setpoint of 60% would be an upper-bound limit, a "dehumidify to a maximum" not a "humidify to" number. This would be to keep the humidity below the high mold-risk potential during humid-air summer ventilation.
An interior RH that high is risky for wood-sheathed buildings as a wintertime setpoint in colder climates. It would demand true perfection on air sealing between the sheathing and the conditioned space (and lower vapor permeance too) to keep the sheathing from getting moldy. The dew point of 70F / 60% RH conditioned space air is about 55F, which means any time the sheathing is lower than 55F any conditioned space coming into contact with the sheathing will be adding to the moisture burden. In US climate zones 4 and higher the outdoor temperatures are lower than that for most of the hours in a year.
A 60% RH is also higher than health professionals advise, since it's a humidity level at which dust mites populations explode, fungal infections of the skin can get started, and on the threshold of mold blooms too. Health pros put the upper bound of at 50% RH, even though most people tolerate 60% well.
Dana explained my point of bringing up the 60%RH better than i would've done.
AJ: Richard has provided many many words and no explanation on energy savings as of yet.
I did not wish to offend Richard, but i've been asking for basic numbers
of COP or efficiency to try and UNDERSTAND why he is so vigorously defending his work and hydronic systems as being more energy efficient. .
Still waiting Richard
I'm not interested in specifics on a X project or setup
i wish to know, how you achieve high efficiency of energy on your system
for water heating/space heating
please ( is that polite enough ???)
Jin ,
Hydronic systems are the only way to achieve all ASHRAE standards in a house . This along with DOAS are the path to healthy buildings and after that fact healthy , productive people . Look into ASHRAE standard 55 , for soon it will be the recognized standard . As opposed to what I have witnessed through these last couple of days and discussions I design systems for the occupants , not the building , I also design for comfort , in case you did not know comfort involves all the senses which human beings possess . here are your basic numbers for this home in the link . Remember that while the system was running for the first several days we were charging a slab to steady state and the doors were wide open as folks moved in and workmen finished their jobs .
Htg Load x 24 x DD x CF 91000 x 24 x 5250 x .605 6,936.930,000
_____________________________ = 1,229.952 Therms x .92 per
AFUE x Q x DTD .94 x 100,000 x 60 5,640,000
Q = BTU content / fuel unit
DTD = Design temp difference
CF = correction factor ( Table C , IBR H-22 manual
Answer is 1,131.556 Annual gas usage .
A bit more math that is area specific . 1,229.952 therms = 36,047.831 Kw 36.047.8 x .14 = 5,046.69 dollars. If you used electric stuff with a COP of 4 you still would have spent 1,261.67 . There's your plain and simple math . True thermal comfort , plenty of hot water , peace and quiet , no noise , no air blowing around . Just warmth .
By the way , many of the folks who I work for will not accept the look of panels on the roof or ground and would never tolerate hearing HPs in there homes . As Aj stated , these are people with money . Take a look at the next link , think this guy wants to use Mini Splits . 22,000 sf home . 8,000sf snow melt in driveways and 92 x 24 front porch . Pay that electric bill . This job went to another contractor by the way , one I know , I'll be in there within the first winter , guaranteed .
http://ramirezarchitects.com/in-progress/shadowlawn-house.html
Please see the chart I attached below also . Just noticed how the math looks different than the way I entered it , sorry . Sure you'll figure it out .
One more point , I performed the wet work in this house and had nothing to do with A/C or RH except to argue with the tin guy and council the homeowner . I would have chosen 50% Dana , but as I read the attached link above 60% is mentioned .
A 22,000' house heated with mini-splits WOULD be quite a spectacle, eh? ;-)
A 22,000' house is something of a spectacle no matter what, and probably beyond the 4-sigma tick on the distribution of house sizes in the US.
Keep conflating therms (a unit of energy) with kw (a term of power), just to force the reader to into interpretation modes, eh? :-)
Since "BTUH" means BTU / hour ...
..and...
..."KWH" means KW x hour...
....you can't just "divide both sides by H" and end up with meaningful units, since one is a unit of energy, the other is a unit of power. A therm is 100,000 BTU, a KWH is 3412 BTU, so the conversion is 29.31 KWH = 1 therm, or dividing out the "H", 23.21 KW = 100,000 BTU / hour.
Nobody is arguing that mini-splits or Daikin Altherma (which probably would beat a COP of 4 in that climate in a hydronic slab application) are going to be cost competitive on marginal-cost with natural gas in every market. At 14 cent electricity and a likely COP of 3.5 or a bit higher (in a NJ location) it would be competitive with gas at New England residential rates.
In New England 1,131 therms would cost more than $1,261.67 (the calculated cost if heated with heat pumps at a COP of 4 with 14 cents/kwh electricity), but in New England the cost of electricity is also substantially more, and the seasonal efficiency of mini-splits lower than 4.
Missing from "...your plain and simple math..." is the annual cost calculation of the natural gas usage, which won't assume to be zero simply by virtue of it's absence. For the record, if you can convert therms to USD, Euros, Rand, Yen, BitCoin, (any currency but Rubles :-) ) we'd be better able to make the marginal cost comparison.
The power use of the hydronic system also hasn't been calculated, thought that is arguably one step beyond "...plain and simple math...".
The more complicated lifecycle cost math is still important, but there aren't many reasonable ways to heat 22,000' buildings. Low temp hydronic GSHP or condensing gas are probably the more reasonable options, with natural gas being cheaper than GSHP on a lifecycle basis.
There's only so much that makes sense when comparing a 22,000' mansion to a more typicaly house 10% that size, and with a budget less than 5% that of a luxury mansion. But getting the heat load of a 22,000' house that low is no mean feat, despite the fairly optimal shape. There are plenty of existing 2200' houses in NJ that use more than 1,131 therms for space heating (but those houses don't even meet current code-min.)
Dana ,
You are correct . I did forget a step in my conversion . 1,229 therms at .92 = 1,131 . At further look the conversion is right . Correct me if I am wrong but a KW is 1000 watts just as a kilogram is 100 grams . A therm is 100,000 BTUs . power is energy and energy is power . You just stated that it also
29.31 KW = 1 therm . correct ?
29.31 x 1229 = 36,021.99 , Sorry but if you add an H the numbers don't change .
Did you miss the part about 1,229 therms is 1,131 dollars or did I really need to locate a $ sign in the equation . I pout the information in very nicely but when it posted it got to look like what I would call jumbled , Again , I apologize as I did when I edited the first time .
Again , every job is area , customer , building specific . We cannot , any of us use a boiler plate system . Hell I use all kinds of fuels , equipment types and control and piping strategies . They are all different .
By the way dana , hydronic slabs are very difficult to control and guarantee comfort with . Mass has a new address and it's in a better neighborhood at the area of the boiler . In this way we can prevent all kinds of nasty thing s like short cycling , overshoot , slow response .
Richard,
You are going to drive us nuts.
You wrote, "Power is energy and energy is power."
No!
Power ≠ energy.
Energy ≠ power.
Since this appears to be a new concept for you, I suggest you read Understanding Energy Units.
Power is energy per unit time. Just as miles per hour is not the same as miles, power and energy are not the same thing, any more than speed is the same as distance. Though there is a relationship (distance is the numerator term, but not a unit of speed) it's sloppy and often confusing to use kw for kwh, or BTU for BTU/hr. It's sometimes obvious in the context- a 100,000 BTU burner, for instance, since burners do not contain units of energy, they are specified at an hourly energy rate. But when you're skipping between a heat load number (which is a power number), energy content per unit of gas, and or annual energy use (also broadly power number, but you are specifying the unit of time= "annual") , the intent can get lost in the translation.
Thus 29.31 KW is NOT equal to 1 therm. 29.31 KWH = 1 therm, neither which has a time dependency.
29.31 KW is 100,000 BTU per hour , both of which are power, time dependent, but on different unit of time (Joule per second vs. BTU per hour). But 100,000 BTU per hour is also 876,000.000 BTU per year, or 27.7778 BTU per second, or 1667 BTU per minute. The units matter, the numbers change, and the "H" counts, since it defines the unit of time over which the energy is being distributed. We all use units of energy per year or energy per second or hour in different aspects while discussing heating & cooling, and the units really do matter.
Yes, you really DID need to put the "$: in front of the 1,131, since you didn't actually write " 1,131 dollars", or give a dollars per therm rate. What you wrote was: "Answer is 1,131.556 Annual gas usage." Who the hell uses 1/10 of a cent units when talking US currency, other than at a gas station or electric power rates? Nobody rounds to the nearest $0.001 when using annual cost numbers, they usually stop at the decimal point. I really had no clue what that number meant in that expression. (But I'm blind, remember? B-) )
BTW: Yes, a KW is indeed 1000 watts, but a kilogram is more than 100 grams (typo?)
I agree that controlling slabs is a bit unruly and that it's easier to control a system with the bulk of the thermal mass inside an insulated buffer. The slab reference was only to imply "very low temperature radiation", which can of course be had by other means. (I designed my own home's hydronic system buffer-centric since the individual room loads were way too low to count on modulation. In retrospect I coulda done it with a Versa or Phoenix, but didn't.)
Hydronic heat is used in some houses. What I was hoping to do with these threads is discuss building the best hydronic systems. Can we do that?
Do we have to keep discussing KW verses KWHr or $1.00 verses 1 dollar???????????????
Richard obviously is a dang good hydronics person. I don't care if one home is not in the norm Dana, there is not one person alive who needs to be told that as we all know that. What we don't all know is how to build an hydronic system with modern boilers and modern circulators and modern piping layouts that use the least amount of parts to do the best job.
Please can we learn about hydronics? Please?
By the way Dana, where I build much of what is being built is far larger than a home you or I own. That is the market here and in much of the country for hydronic systems.
And yes, I love mini splits. Love em. Want one!!!
So we have a hydronic person here to help us with hydronics.
I love this fact. But I guess I am in the minority here again and again and again.
ECMs are a great circulator and anyone reading these threads should look into there use if you have a hydronic system.
Richard, A.J., and Jin,
It doesn't matter if this is a green web forum or a hydronics forum; clarity is still valuable.
It's important to distinguish between a kW and a kWh for two reasons:
1. When you use the right units, your writing is clearer and easier to understand.
2. If the author is uncertain of the units, there is a good possibility that the author doesn't understand the topic being explained. Since anyone writing on this site doesn't want to be misunderstood, and doesn't want to be mistaken for an author who doesn't know what he or she is talking about, we need writers to use the correct units.
All three of you would occasionally benefit from slowing down and thinking through what you are trying to say before you rush to the keyboard and click the "Post" button. If you have some thought to share, please take the time to write in a sentence, with punctuation, and with the right units (kW or kWh) affixed to your numbers -- for everyone's sake.
(Et oui, Jin, je sais que c'est malheureusement difficile quelque-fois d'écrire en anglais... une langue difficile...)
( Ah , jamais aussi difficile que le francais, que vous maitrisez toujours aussi bien :)
Pas d'excuses pour mes manques grammaticaux en anglais mais bon ...je tacherai de faire mieux
maitre Martin :p )
deleted ..
Richard: while it is obvious to everyone that you design/build high quality efficient hydronic systems, and i do not think anyone here doubted that, using natural gaz for heating on efficient condensign units (90%+ eff. right? ) does not consitute a "green" feat in itself, it is an economical/comfort based decision.
At your current local prices, i can easily understand why a client with a "mansion" 7K sq.ft + house will benefit from using your NG hydronic systems both for comfort and for economical reasons.
( 0.92/therm is equivalent to ~0.03$/KWh ...am i right on this? i am a n00b when it comes to NG , therms etc.. )
Unfortunately the future cost of NG is unknown,
though i doubt that this would be of concern to the owner of a 7000sq.ft house.
Do you have a pricing idea you could share with us for this particular setup ?
What about similar system but sized for a small very efficient house ?
So shall we try to move on with this and go back to topic of AJ, which probably concerns you more than anybody else here.
Jin, hydronic set ups are much more expensive than the least expensive hot air set up.
In my area, for example say one quote I had, simple hot air with AC NGas $5-10,000 depending on a few things and home size and whether in a development or custom one off. Twice that for hydronic and AC or more.
You are right that hydronic is a choice. These days it goes into custom more expensive larger homes. What else would you like to know?
Price shoppers go with basic hot air and soon enough will use mini splits if ever super insulating PGH homes start to become popular. With the price of oil dropping, won't happen tomorrow.
I posted it before but a new home was resold and remodeled lately here, and the bid I was looking at had to be $200,000 just to update the heat system during to remodel. Not my home size but we have a lot of them going up.
Anyway, hydronics are fun, interesting, it's water flowing, I love it. And am ready to switch to ECM circs. when possible.
AJ- I'm as happy as anyone to have a competent "wet head" posting here, but the looseness of terms is confusing sometimes, and in potentially consequential ways.
Did anybody REALLY understand immediately (or even on the second or third read) that "...1,131.556 Annual gas usage. " was in units of dollars? I was thinking it had to be some unstated therms to CCF number at whatever mix was coming down that local pipeline or something, then decided that it had to be therms, somewhat contradicting the calculation's he had posited just prior to that number. Maybe I'm an idiot (probably am- just ask my wife :-) ) but it seemed like some random number, the result of some calculation that hadn't been included in the writeup (which in fact it was.)
I apologize if asking for unit clarification wrecks the thread, but it's not going to wreck anybody's carpal tunnels to add the "H" or "$", where appropriate, and it sure makes the content a lot clearer.
Mon établissement avec le français n'est que légèrement mieux que mon Hindi. (Online translation. Yes, it's that bad! :-) ) But my comprehension of both financial & design math, and the relationship between terms & units related to energy & physics is better than either.
The fact that the budget, scale, and design of the house is different from what most people can afford to build kinda does matter, when one is posing the approach as a paradigm to be followed even by those of lesser wallet (as Richard seems to be proposing.) A lot of extra-comfort issues come with a price tag others may not be willing or able to afford. Micro-zoned hydronic heating has the comfort edge in the bag, but it's not the only way to reasonably heat a house, particularly very low load houses.
Response to Martin .
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Richard,
You are going to drive us nuts.
You wrote, "Power is energy and energy is power."
No!
Power ≠ energy.
Energy ≠ power.
Since this appears to be a new concept for you, I suggest you read Understanding Energy Units.
Answered by Martin Holladay, GBA Advisor
Posted Tue, 12/16/2014 - 18:34
Martin ,
I am quite familiar with communicating with my peers . When we are engaged in a discussion it is customary that we have been paying attention to each olther and not being dismissive or sarcastic and can quite easily distinguish whether ewe are talking about BTU/h or KW/h at any given time . Your regulars however have some sort of complex where they think they should pick apart someone whose methods are different than what they read in some paid for study .
I do find it quite amusing that most of the rating agencies and labs have hydronic based systems within their confines , NREL , ASHRAE , I could go on but won't .
As to your reference of me being new to this and my punctuation , grammar and the like professor , you are sadly mistaken . The math above is an annual fuel consumption estimate , maybe you and your crew here have never seen one because someone else did not publish it . It was quite clear when I entered it but got jumbled when posted . I am just a lowly hydronics designer , not a very good keyboard operator even when I am capable , more about that in a moment .
BTU/h would be 91,000 , hours would be 24 , Degree days would be 5,250 and correction factor would be .605 .
The second part od the equation would be AFUE .94 , fuel content (not/h) 100,000 ( if the fuel were electric the number would be 3412 , not 3412/h) , Degree temperature difference 60 .
Now lets do the math
91,000 BTU/h x 24 hours x 5250 DD x .605 = 6,936,930,000
.94 AFUE x 100,000 content x 60 DTD = 5,640,000
6,936,930,000 divided by 5,640,000 = 1,229.952 therms (for integrity sake , I just corrected this , it said BTU) , per year . If fuel was electric the annual usage would be 36,047 KW .
Nat. gas usage 1,229.952 x .92 = 1,131.56
There , that should post right .
As for my punctuation and formatting , that is not my strong suit admittedly , however , in face to face debate no punctuation , formatting is necessary and that is what my day to day consists of and I am very good at it . Besides not being a very good keyboard operator to begin with I suffered the near loss of my left ring and middle finger in October and am further challenged . Stop breaking my balls for trying to share valuable knowledge with your readers and folks who need help from someone truly qualified .
I will share no formulas , math or the like as these are all things I get compensated handsomely for and have decided not to give it away for free and on top of it spend a couple hours a day trying to explain it to non peers and confuse them further .
Dana ,
I do not believe for a minute you that stupid to not know what i mean when I post . Stop being a provocateur and antagonist .
Daniel , Thank You . If I ever require help in design I will reach out to you .
Martin , In case you forgot , we are supposed to be building healthy buildings . Not just so the building is healthy but the occupants also . First cost has nothing to do with that goal .