What is your location?

What do your quoting dealers have to say?

Ask for a load calculation.

What is your cost/gal for oil; what is your cost/gal for propane?

Propane prices normally track oil prices. Of course you can get a high eff condensing propane boiler, but you get more BTUs from a gal of oil than a gal of propane. So you need to understand both efficieny and cost of both fuels to make a fair comparison.

I would think no more than a 125-150 KBTU boiler but that's just an educated guess depending on your location.

If fuel operating costs are close and there might be a chance of nat gas service down the road, I would lean toward propane. Anything about AC?

Just a few rambling thoughts.

IMO

tigerdunes thank you so much! The reason I am so confused is the load calculations seems to be all over the place. We have gone from 150,000 to 200,00 btu calculations. I went on line myself and seem to have 105,00 heat loss calculation,
Right now 4.12 for heating oil and 3 for propane. We are in climate zone 7 4100 heating hours per year. The biggest dispute seems to be how to calculate the load for the stone construction. Anything would be an improvement over the astronomically high bills last winter, but i want this furnace to last

Give me an idea of your location. I don't have time to look up these zones.

Did you get the load calcs in writing on the software letterhead? You should; that way you can make a comparison as far as design temperature used plus possibility of any errors.

Here is a down and dirty fuel comparison. 85% eff for oil, 95% eff for propane.

Cost per 100,000 btu of useable heat

Oil: $3.51
Propane: $3.45

Basically a wash.

Again any chance of nat gas service down the road?

IMO

Well, since you are a money pit... ;-) here's something else too consider. I swapped over to gas from oil three decades ago. The furnace was tiny compared to the oil-fired behemoth from the fifties. Natural gas - or propane - allows you to cook when the electric power goes out. Does that happen frequently in your area? I've got an 8kw, tri-fuel, standby generator that will run on petrol, propane or natural gas. Going with gas might be something to consider.

Another element in the equation is the age of the oil tank if it's in-ground, as steel tanks have a finite lifetime. Some communities still allow tanks to be pumped dry, then filled with sand to render 'em inert. Proper removal or mitigation gets pricey right quick.

Cheers

This post was edited by apg4 on Tue, Jul 15, 14 at 17:15