Heat pump recommendations (central system)
I have been lurking here, pretty much since I bought my first new home, (11 years ago) and realized how little I knew about this huge purchase.
It’s a 1650 sq. ft. two-story house, in Montreal, Quebec, (zone 5a) built in 2007. It has central heating, electric furnace with the original 2.5 ton heat pump, which has just let go.
So I’m in the market for a new heatpump, and possibly a more efficient furnace to go with it. Of the 5 quotes I have had to date, nobody has suggested a manual J, and salesmen look at me like I’m an alien, if I show them the heat load calculation data that I have. Knowing that most systems are oversized, would it make sense to go with a variable speed heatpump and furnace?
I have seen talk of how it is hard to goof up on over-sizing the newer mini splits because of their ability to ramp down, and have seen a few central heat pump systems that can do the same.(obviously with less efficiency) On company has even suggested going up to a 3ton, because it can ramp down 50%. Does this make sense?
The home has been tested through the local energy audit programs, and has estimated that the home’s design heat loss would be 29900 Btu/hour, cooling load would be 18200 Btu/hour. Air tightness is 3.39 ACH/50
Any input would be appreciated.