Question about ductless minisplit heat pumps
I live in a 1275 sq. ft. Cape Cod in southern New Jersey (zone 4A). My house was built in 1980, is two levels, is somewhat well insulated, has an unconditioned but insulated crawl space, has dual-pane Andersen windows (manufactured in the early 1980s), and it has asbestos shingle siding.
Prior to closing on the house this past January, I had a friend who is an HVAC professional assess the heat and cooling systems of the house. Heat is a 100,000 BTU propane-fired forced air system, while the air is a 1-ton Bryant central air system. My understanding is that a 100,000 BTU heater can heat a house three times the size of mine, but this heater was manufactured in 1996 and I have no idea what the efficiency rating is.
My friend the HVAC professional told me that the heater was on its last legs and he recommended a 5-head Mitsubishi ductless heat pump for $11K – of course I balked and I got a second opinion. Another friend who does plumbing and heating just replaced a control valve for a few hundred dollars and the propane heater is fine.
However, propane is expensive at $2.75 – $3.75 a gallon depending on current demand, and with the return ducts in my small house it often sounds like a 747 is landing in my living room. Plus, the heater itself is massive and it takes up over 1/3 of the crawlspace, so it’s a huge pain in the neck to service it and to replace filters, etc.
I really like the idea of the DMHP, but I really don’t think that I need five heads to the tune of $11K for a house my size as my friend recommended. ALL of the rooms in my house are less than 400 sq. ft. and most are less than 200 sq. ft. It’s my understanding that the smallest heads at 9000 BTU are too large for most of the rooms in my house.
Then I come to this site (GREAT FIND) and I read about homeowners who are heating homes of my size with a one-head system and some have a second head for cooling. I’m certain that my house isn’t as well insulated as homes using one head (envelope? noob here) but the house is well insulated in general. So I’m thinking that I could have the two-head system work in my house — now I’m talking $5K as opposed to $11K. Now I can get rid of my propane heater and the project would pay for itself in three or four years.
Could anyone out there offer any thoughts or suggestions?
Chris in NJ
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