Engineer ambushes salesman, or “what do we do about HVAC?”
So at this point, I have done a Manual J load calc for my house that puts the heat load at around 20,000 BTUs. I know that I want an electric heat pump so I can eventually go net zero. I *think* that I want it to be the Bryant Evolution 280a, which has the highest HSPF (13) that I’ve been able to find in a ducted heat pump. Seems simple enough, right? “Quote me an installation for this unit.”
But so far I have been unsuccessful in getting any HVAC companies to bid. Not one. Four salesmen have come by, and no bids. Zero.
I reeeeeally try to avoid being the nightmare engineer customer, but none of them want to install what I’m requesting without some explanation, which inevitably reveals that they have no product knowledge for anything besides gas furnaces, let alone how to size a unit properly. One guy told me that a heat pump simply wouldn’t work, full stop (climate zone 4/5). Another one didn’t know that heat pumps came in non-minisplit configuration. Another didn’t recommend heat pumps because he said the supply air temperatures would be uncomfortably low (what is this, 1995?). Yet another insisted on quoting mini-splits and initially specified a 12k BTU heat in every bedroom before I protested (never actually got the quote). All of them have estimated grossly inaccurate heat and cooling loads ranging from 40-90k BTUs for my house.
Today’s salesman was actually interested in why my Manual J calculation was so different from what his crude app said. We went over his app’s output line-by-line and I was able to point out the exact errors built into it. For example: hardcoding an outside temperature of 0 degrees instead of something appropriate for the climate (18); only going up to R-30 for attic insulation; using a u-value of 0.96 for double-pane windows instead of something reasonable or letting you input a value (my windows are U-0.26). I could go on. I doubt I’ll get a quote from him–same as the last three.
What’s to be done about this craziness? Am I going to have to become a licensed HVAC professional myself just to install a freakin’ heat pump?
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