You might find this link interesting. Oil is cheaper for the heat output, but then you would need a tank and yearly or possibly every two year maintenance.

Here is a link that might be useful: Fuel comparisons

I'm from down here in the south and we don't have oil burners here, though I have a general idea on how they work, since I did help fix one back in the 70's.
Has anyone ever tried modifying the system for using used motor oil or cooking oil in them? Seems that would provide a chance to get free heating in part. Just curious..

Thanks Baymee:

Looked at that fuel comparison, seems like oil replacement is the best option. At my age (61) I also have to look at payback time. Here in B.C. Canada, we have gotten a price for a new 86% effecient oil-boiler at $3600 installed. And we already have a 250 gallon tank. Wheras, the propane boiler is $7500 plus, including installation.

As for daddo, yea, could look at cheaper fuel, but we do buy the more expensive bio-fuel. 20%canola-80%oil. Eases my conscience a bit-lol.

Just in case you guys were wondering what it costs to heat a 1700 sq.ft. home here, it goes like this= 4 cords firewood-$660-60 gallons propane-$275, and this years total oil bill was-$720. or approximately $1700 per year.
I suppose in todays world, that isn`t all that bad. The reason for the different heat sources is this old house is a four level split. *And when the power goes out cause of a wind storm, we like to have that back-up.

Thanks again for the feedback. George

Daddo, there ae several companies that make waste oil furnaces and places that have large fleets of vehicles or other business' that can get hold of vast quantities of used oil find them handy. But they can be a maintenance nightmare if you aren't careful with what your burning of you get lax with normal preventive maintenance. The don't burn clean either so its not something your neighbors would not appreciate either. Check out Reznor Waste Oil furnaces.

Daddo, oil burners have significantly improved since the '70s. Nowadays, they produce no smoke. I am very familiar with a waste oil burner, having run one for 3 years; securing the raw vegetable oil and motor oil, filtering it, and using it for heat. They don't burn as clean as an oil burner, but most of the time, there is no visible smoke.

$3600 is an excellent price; almost too good of a price for an installed oil boiler, even in the USA.

My family has been in the heating fuels & equipment sales/service/installation business for many decades. We've never used AFUE as a sales tool since we install *systems*, and AFUE doesn't show system efficiency. The ultimate efficiency of an oil fired system is in the hands of the installer/system designer & burner tech. Proper sizing, piping, zoning, control strategies, and burner setup are what make the difference. Many systems I see are oversized, poorly piped, have no zoning and burners are setup poorly.

Oil fired boilers are the norm in my area of the Northeast.

$3,600 is a pretty cheap price. The only guys installing boilers for that in my area don't perform heat calcs, and don't include new backflow preventers, low water cutoffs, feedwater valves, air scoops, expansion tanks, isolation valves, oil filters, firomatic valves etc. (combustion testing optional) LOL, I used to work for a few outfits like that.

"(combustion testing optional) LOL"
you get the old fashioned combustion test, lift the door, look at the color of the flame, "Yep, that looks good"
Bachrach, who's he? We don't have anybody working here named Bachrach! LOL

Thanks everyone:

The replacement boiler is an Airco-Olsen. From what I have read, this is a decent quality product. Depending on nozzle size-btu output is variable between 78,000 and 120,000 btu`s. My current old American Standard says it has a maximum output of 83,000 btu`s. So this new one looks like the right fit, maybe even able to drop down to a 0.65 gph nozzle.

We only have a one zone heat system, but with the auxillary heat we only burn 700 litres per year. So, even with a new boiler, I doubt that we would lower our consumption to much less than 600 litres. Thats why I said,"if I replace that old boiler"-lol. Also, just love that wood heat-cant beat it for comfort. Thanks again for your input..George

propane piping should be hardpiped for safety. galvanized outside black pipe inside. 90k btu per gallon. #2 fuel is
140k per gal. you are correctthat your useage is low but a new riello burner is superefficient and clean in an old unit
definitely advantageous

'you get the old fashioned combustion test, lift the door, look at the color of the flame, "Yep, that looks good"
Bachrach, who's he? We don't have anybody working here named Bachrach! LOL'

Oh the time I could save if I didn't use a wet kit, electronic combustion tester, didn't test pumps, didn't check/replace pump strainers, didn't check safeties, and filled out the service tags with made-up numbers.

I know plenty of techs that say they can tune a burner by sight and sound. These are the same hit & run types that perform half a dozen plus annuals per day.

Dream on but don't waste your money on a changeover. Your cost per BTU is significantly MORE with propane which would rule propane out as an alternative.
Now if you think that an impovement of 7% justifies investing $3600 for a new oil fired boiler then consider the following:
The math is simply this. You are spending $770 per year , so your savings would be 7% (93%-86%) of $770 or about $55 per year.
Take the cost of the boiler and divide by $55 and you get 65 years to get your money back. It gets worse; if you put that $3600 in a bank you could get (at 5%) $180 a year in interest so the answer is you can NEVER get your money back. In fact, you would be losing $125 a year forever.
So, despite the fancy claims, forget it.

Many thanks joeplumb:

You are right-on!! Even though this old American Standard boiler is 34 years old, it has been good to us and still is, we have replaced the motor twice, and the circulating pump twice in 20 years, and aside for our yearly maintenance ($130) it doesnt owe us anything.

And like I tried to explain in one of our earlier posts, it isnt a panic situation if it quits, we have a propane insert and a wood insert for heat as well. Since I retired 3 years ago I have experiemented with organizing our heat, and found that if I run the boiler until the temp reachs 70 degrees, then the wood insert will maintain that temp for at least 4 hours until the boiler kicks in again.

No, I think we will just keep it, and take your advice and not spend the bucks -if it aint broke dont fix it. thanks again.