I continue to mull new equipment to replace my 9 year old oil fired hot air furnace & Lennox heat pump, especially since there appears to be an unusually good opportunity for better pricing due to a lack of business for even experienced contractors.
The general consensus among all contractors I've spoke to is that the old furnace is substantially over sized. It has a non-changeable (per the Mfgr.) 1 gph nozzle thus resulting in an approximate 111,000 BTU/hr output (138,800 x .20 efficiency loss). Only 2 of the several dealers I contacted would do a true calculation. Both came up with a +/- 56K cooling load and 75K heating load. Guess which dealers I would use?
I am contemplating switching to propane via a Carrier Infinity system & ICS 58MVC furnace plus a 5 ton 25HNA9 heat pump and comfort 2 zone control. Propane is in the lead since oil is, IMO, likely to be harder to get as the years go by due to global BS, more maintenance intensive, less efficient and far dirtier. I also like the variable/multi staging aspects due to comfort and possible increases in efficiency. Why fire 111K btu when all we need is, say, 60K?
So, here is my quandary: Is it possible to determine based on past usage how much fuel/energy a new system WOULD have used were it installed in years past? I ask this since it is impossible to predict future conditions, but do think one can ask "Well, if I had this installed last year what would I have used?", which then answers the "So, is the investment in new equipment worth it? question.
I figure if I can see a payback in roughly 4-6 years, assuming similar fuel pricing in the future, it's worth it. I'll invest for a longer term benefit, but can't see spending 5 figures just to switch equipment color!
Background details: 2800 s.f. open foyer colonial in NY, 9 years old w/ R19 walls, R 30+ attic, Anderson low E glass and quite a few windows. Average annual oil usage: About 850 gallons. Total electric bill is about $2400/year. Obvious energy loses/holes already plugged.