I would appreciate a review of an air-source heat pump quote
zone 7 Kenora Ontario, Canada.
I asked for a quote for an ASHP unit that would work for the time being as well as in the near future when the house is expanded…
Some background….
1-short term.. (with the building as is)
-to heat and cool my existing home, 850 sq ft 2×6 framed 20 yr old bungalow on conditioned 5 ft insulated crawlspace…
I completed an online manual J about a year ago and determined as best I could a heat load of about 25000 btu.
and…
2- Longer term, 2 yrs from now (expansion to 1900 sq ft) R30 ICF basement on expanded side with 4″ EPS foam on ENTIRE building from footer to roof line. 6″ EPS under the slab of the new side.
All windows are now 20 year old triple pane casement, will be replaced with new low e argon triple pane, assuming u.25 (Jeldwen 7000 series casement and fixed), R60 cathedral ceiling R 36 walls (2×6 with 4″EPS).
4 ft overhang on new side, 2 ft on existing. Glazing about 20% (its a lake house).
The manual J I completed for the building…taking into account the renovation to the existing as well as the new build showed a heat loss of about 60000 btu. I must confess though that this was much harder given the cathedral ceiling, ICF basement walls and foam on the exterior.
I am trying to get a system that is neither too big for right now and right sized for the future. That may seem foolhardy BUT…. my electrical company (HydroOne) has a brief window (July 31 Dec 31) for a new program that refunds up to $4k for an installed ASHP system. I can’t wait for two years since the program has a best before date and must act soon..
I asked for a quote from a local company…indicating I wanted either a Mitsubishi or Fujitsu hyper heat model, I was open to either mini splits or other. I have recently decommissioned a forced air oil furnace (80k btu at about 75% efficiency) and added baseboards to provide heat if no ASHP is in my immediate future and emergency heat if an ASHP can’t provide sufficient heat at the coldest temperatures.
I would appreciate a review of the equipment referenced in the quote for any thoughts as to size and applicabilty.
PUZ-HA42NHA5 VRF heap pump outdoor unit
EH17-MPA-L AHU heater
PVA-A42AA4 indoor vertical air handler
PAR-32MAA-J Mitsubisi was controller
ME-0001 Me curb mount stand
$13871
labour and line sets EXTRA
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Replies
I have to pull the trigger on this or a similar system soon....anyone have any thoughts whether these are appropriate for my application?
Tim,
I'll provide some feedback, but (as you might have guessed) it's hard for GBA editors or readers to provide the full services your require -- namely, heating and cooling load calculations, heating and cooling system design, and equipment specification. For more information on hiring professionals for these services, see Who Can Perform My Load Calculations?
In your case, you are planning to deliberately choose oversized equipment, with the idea that a future addition will increase your heating and cooling load. Since most systems in North America are already oversized, that approach is risky. It requires you to be very tough on your Manual J calculations -- you want to be aggressive and strict about your inputs. You need to be ruthless: You need to do your best to pare down your loads, so that no padding occurs.
could you not have 2 systems? Install a mini split (or 2 if you heat load calcs are correct) now, and deal with the expansion when you actually do the expansion. god knows what will change in that time, and you dont want to lock yourself into a floorplan/layout just because your 3 year old HVAC is sized specifically for it.
I like Ryan's suggestion a lot. Additionally you may find that the new space is used at different times or has different solar gain. You may find it easier to achieve comfort quickly in the new addition with a separate system.
What about using the heat pump on your existing house only and including a mini split system (single or multi) in your addition? That should reduce some possible challenges like tying the new ducts in the addition into the old ductwork.
Nb: I'm just a diyer but have been struggling with heating and cooling for some old additions and their poor connections to the main duct system.
Some great ideas...I will be talking to another HVAC Co. this weekend to get a better handle on my options and pricing.
I thought the price seemed pretty sky high considering there were no line sets included and no labour! Or maybe I'm wrong.... are these prices reasonable?
The cost of mini-split units spirals out of control very quickly once you increase the BTU output. Your plan doesn't make sense, but Ryan's suggestion does. It doesn't take a lot to heat 850 square feet. Install two of whatever that turns out to be, but one at a time.
An inverter based heat pump (as you are considering) at the oversizing you are looking at will outperform a correctly sized single speed heat pump.
I can't disagree with the logic of going with a single mini split for the existing building and adding another later. In defense of my first plan I was desperately looking for an easy way to serve the future needs as well...I think that I'll abandon that!
Could I get some help choosing the right equipment (Mitsubishi or Fujitsu) for my heat load? The heat load of the existing side will decrease somewhat when I add the 4" of foam to the exterior in the future and new windows. Since I'm increasing insulation ??% will my heat load decrease by the same ??%
In a perfect world it would be sized to provide adequate heat at full blast now and modulate with the improvements in the future.
Jon R.... I'm wondering about your comment... do you mean I SHOULD or SHOULDN'T consider my proposed plan?