Your electric rate seems too low for the New York State region. Are you sure it is correct? If it is, then a heat pump will be cheaper to operate than an oil fired boiler.

What is the total area of the first and second floors? The best solution is to have a separate condenser for each floor. However if you are putting in new duct work, you should be able to keep floors at the desired temperature with one system and zoning.

No one on this forum will be able to advise you if a 3 ton system is adequate. You need to insist on the contractor performing a Manual J load calculation and giving you a copy of it to you. You have an old house which I presume has little insulation in the exterior walls. The calculation needs to be done carefully with some assumptions about insulation and air infiltration.

That was off the central hudson website, so have to assume it's correct...

The total area of the first and second floors is 1740 sq ft. This would be all new duct work, and I plan to spray foam the entire house as I have all walls open right now.

Thanks

To get a true electric rate, you need to calculate in all the surcharges and adjustments on the bill which can be substantial. If you have a bill from that company, just divide $/kWh and use that figure. Maybe they have a sample bill on their web site that would allow the same thing.

Is nat gas available where you live? What kind of shape is the boiler and tank in?

The Hudson Valley covers a surprisingly large climate range or is Hudson Valley the name of a burg? No matter, Mike_home's statement about the need for calculations is correct.

(Maybe crazy) idea for the pros here, but could the oil boiler be kept used for backup heat with a coil for the forced air? It might be worth considering for three reasons, first, cost could be favorable to electric strips, second, heat could be powered by a small generator in case of outage, third, you could use the oil of domestic hot water if gas is not available.

Good idea on the bill.

Gas is not available. Boiler and tank are new in 2007. The actual city is New Paltz, NY.

Adding a coil to the boiler is an interesting thought. Thing is the cast iron is all removed so I'd have to do something like like that to tie into the A/C ductwork that is not yet installed.

I am not a heat guy, but I am relatively certain that you can use your boiler to make DHW and heat the forced air. There are details that I can't address. The trouble with using it for back-up heat only is that it might be too expensive to keep it hot for stand-by heat. If you are using it for DHW, that would not be an issue. It may be way over capacity for hot water only. I don't know if that is a problem.

That is a very new oil system. I suppose you could sell it if you don't need it. It is new enough so there should be some interest in it.