Green HVAC contractor
Salesi
| Posted in General Questions on
How can you go about finding an HVAC contractor that will provide a “best” solution based on your house type? We are building a new 1700 sq ft house on a crawl space with 2×6 walls with 2″ of polyiso and a rain screen. When I can find a contactor to provide a proposal, it is pretty standard based on past experience, blah, blah, blah. One contractor’s proposal was for a 100,000 btu furnace and 13 SEER central air. I guess what I am asking is, how do I find a HVAC company that will provide a energy efficient, green, solution? Not an off the shelf design, one size fits all. Thanks for anyone’s help.
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Replies
You're asking/expecting too much from an HVAC contractor.
Hire a certified engineer or other qualified party to run the heat load numbers and specify the equipment. Engineer's livelihoods and reputations are made on the accuracy of their numbers.
With the spec in hand, put it out to competitive bid with HVAC contractors.
HVAC contractors generally don't have the time or interest in making it perfect- they make their living by installing and maintaining equipment, not carefully analyzing each system and house (and it shows. :-( ) There are a few who can really dive in and calculate the U-factors of non-standard wall & roof assemblies, but that analysis takes time (=money), and that part of the task is more in the wheelhouse of engineers & (some) architects than pure HVAC contractors.
Have you done even a rudimentary or quickie online load calculation using freebie/cheapie tools such as loadcalc.net or coolcalc.com? Or even simple spreadsheet I=B=R type heat load calc? See:
https://www.greenbuildingadvisor.com/article/how-to-perform-a-heat-loss-calculation-part-1
https://www.greenbuildingadvisor.com/article/how-to-perform-a-heat-loss-calculation-part-2
https://www.greenbuildingadvisor.com/article/calculating-cooling-loads
A room-by-room IBR type calculation is usually good enough for sizing the equipment and an adequate starting point for designing ducts.
Apparently I am barking up the wrong tree as they say. Where would I find a certified, qualified engineer that can actually design an HVAC solution for our particular house? Thanks for the lines on heat loss, I will definitely run it for our house. Appreciate it.
Have you tried searching the local phone directory? Calling house architects and asking if they do that as a service or who THEY use for HVAC design and load calculations (as distinct from which HVAC installers they use) might dig up some sources.
Failing that, there are a few companies that will run the loads and spec the HVAC remotely online. A frequent guest-blogger on this site Allison Bailes' company Energy Vangaurd out of Decatur GA runs HVAC design & load calculations as a service, based on the information you give them on the house construction details.
https://www.energyvanguard.com/service-group/hvac-design
Where is the house located?