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Waste Oil Boiler To Heat Shop AND House?

My wife and I are buying a new (old) log house that comes with a 60x90 warehouse with 12’ ceilings. I was thinking of buying a $10,000 outdoor wood boiler. As we discussed our budget last nite, she asked where the wood would come from… Good question!!!



We have several hundred acres of woodlots in the northern Adirondacks… But does the wood magically appears cut split and dried, she asks???



Hmmm… she asks… what about the waste oil furnace I bought 15 years ago? Would that heat the warehouse??? And could we pipe the house from that??? She doesn’t much like my hobby, or encourage it, but at least she was thinking about were I’d be working…



Anyhow, the waste oil furnace I have is a very small unit that requires a constant watchful eye, as the oil drips faster as the shop warms up. And it’s hot air only…



Sooooooo… What about a BIG new fully self contained waste oil unit to heat the shop, and pipe the hot water, via very $$$ underground PEX to the house??? She asks???



The house is about 1200 SqFt, 1 story, well built machined logs with nice modern windows. Also a full basement… Currently heated with Oil hot water/baseboard with an adjacent wood boiler. We have no interest to lug logs indoors, so it’ll sit idle…



We budgeted $10,000 for the new heat unit. The contractor is accross the street for the underground pipes, and I’ll do all the plumbing, electric, and oil tank installation for storage. I’m thinking to have 3 or 4 - 275 gallon waste oil tanks.

Has anyone had experience with Clean Burn or Reznor? CB uses a dry tube system, and Reznor a cast Iron boiler. They’re both 1200 lbs, floor mounted, and the CB is about $1,000 cheaper, but steel, not Cast Iron. The CB uses 2.5 GPH, 1GPH less than the Reznor. I wonder why? The Reznor comes w with a built in air compressor, the CB does not, you have to supply your own air

Have you lined up a supply of waste oil?? Have you ever messed with drain oil, fry oil, waste oil before?? If you have no interest in lugging firewood indoors, you will quickly lose interest in waste oil. Waste oil furnaces tend to be pretty high maintenance affairs. The sludge and impurities make it worse than coal when used for heating fuel…If you could control the “quality” of the waste oil 100% and get it for nothing it MIGHT be worth looking into…One bad batch of oil and your system becomes a hazardous waste disposal problem…

Oil is rated at BTUs per gallon. If a gallon of oil is rated for 140,000 btu a hour per gallons and you burn 2.5 gallons a hour that’s 350,000 btus a hour input. If the boiler is 80% efficient subtract 20% to get the BTU output, So you need to find the total heat loss for your building. That is referred to as a manual J which now is performed using a program to figure out the size boiler, and GPM required four your application. A waste oil burner over 500,000 btu needs a EPA license.

My mechanic uses a waste oil furnace to heat his shop. It works wonderfully, but he does thousands upon thousands of oil changes and runs a waste oil disposal company on the side to supply it. It could be worth it if you can contract with a local source.

How about two waste oil boilers, one for each building.
That seems simpler and more efficient to me.

Have you thought about a geothermal system? With $10,000 to spend, this may be a possibility. You wouldn’t have to track down waste oil–you are using free heat from the earth.

Both structures are basically barns and could not be heated with solar or geo…Circuitsmith makes a valid point about using two boilers (heating units)

“Stumpage”…Since you own an extensive woodlot, you could allow do it yourself firewood harvesting on a “one cord for you, one cord for me” basis…You may have to go “two cords for you, one cord for me” if cordwood is plentiful and cheap…

I have a feeling before you get a clean, reliable waste oil heating system up and running, you will have spent A LOT of money and recovering your “investment” is going to take many, many years…

Both structures are basically barns and could not be heated with solar or geo.

I think that the geothermal heat would work. I live in the midwest and Iknow a couple of houses that heat completely with geothermal heat. I work on a university campus of 20,000 students and in another year the entire campus will be heated and cooled with a $66,000,000 geothermal system. The ground water from which the heat is drawn is a constant 55 degrees. Heat pumps will boost the temperature to the desired level and it is projected that the system will save at least $2,000,000 a year over the coal fired boilers that are now in use. The environmental gains will be very significant. We always have subzero days in the winter and these geothermal systems should work. If these systems can heat gymnasiums and auditoriums it should heat the barn like structures.

The geothermal systems have an advantage over the air to air heat pumps. I have a heat pump and it is effective to about 40 degrees. Below that temperature, a gas fired furnace takes over. Had the geothermal system been more common when I had my house built 21 years ago, I would have had this system installed.

The only way waste oil worked out for me (too much down time with the 1978 units in 1982) was to throw the waste oil (amd I had plenty from a VW shop) on the wood in the wood stove (the only heating in the shop was a homemade stove made from 2 55 gallon barrels on their side,upper was for radiation and lower was the wood.

Probably was not so “eco-friendly” throwing the oil on the wood but the heat output trippled.

That 55 degeree figure sonds low but I am not “Up” on my geothermal specs

Those double drum stoves put out a lot of BTU’s for the money invested…A friend of mine used two old tanks salvaged from a pair of large air compressors…Heavy gauge steel. He fed it big un-split logs and lump coal…Only needed stoking twice a day…It was used to heat a 4-bay workshop which had zero insulation…

That description of the workshop was dead on as long as all doos were closed). It was right at two cord of Doug Fir for the winter. My shop (no lifts) was built around 1920. I leased and did not renew that one as 1982 Northern CA was suffering from so many loggers being out of work.

My uncle heats his farmhouse each winter with wood he chops down throughout the year on the farm. Farmers maintain their fields by cutting back trees that encroach on their fields, and many sell it as firewood. You might be able to find it cheap if you go straight to one or more of your local farmers, and maybe even help with the work.

I may be wrong about the 55 degree temperature. The wells that provide the heat are very deep and several hundred of them have been drilled. The company is now in the process of running pipes all over the campus. I will be retired before the system is put into service–it is reported to be the bigges geothermal system installation that has ever been done in the U.S.

Heat from the buildings will be pumped into the wells in the summer to provide cooling. There is the energy cost to run the pumps, but this is reported to be less than the cost of coal in the winter or pumping the coolant for the summer to the top of a cooling tower.

How much have you budget for insulation ? Wood is a poor insulator though an excellent heat sink that requires constant heat over time to be efficient. Make sure every nook and cranny of air infiltration is sealed in your home and shop. If your warehouse, is stick built, insulate the walls on the inside with solid urethane foam board with reflective backing to minimize heat loss through the wall and ceiling studs which FG between doesn’t do. This can be a do it yourself, “inexpensive project”. Your heating needs are then cut dramatically.

Unlike a log home which needs constant heat source to reap its benefits, the ware house is more on demand unless you own SA. For that reason, I would separate the heating with wood (wood chips are clean and easy to manage indoors) for the home and your oil back up with your waste oil hot air furnace in the warehouse.

IMO, you have what you need, so put your money into sight preparation (insulation and sealing). The foam board works ! I and neighbors have used the building technique for years with great results in our “buildings” and homes.

I own a modern log home. It has milled logs with tongue and groove interfaces, foam insulation and caulking between the logs. A solid pine log has approximately 1.41 R factor per inch thickness. A typical 8" thick pine log has about an R11 rating. A typical stick built 2x6 wall with drywall and fiberglass insulation is R14. Here’s the kicker- a solid wood log has an additional benefit of much higher thermal mass. It absorbs more heat during the day (than a stick built wall) and gives it off at night. This increases the apparent R factor by about .1 / inch by most estimates. 8" log is now around an equivalent of R12. That’s not exactly a heat sink by comparison.

My home is built with 12" pine logs and easily outperforms “traditional” stick frame construction in efficiency. It stays warmer through the night and then cooler through the day as the significant mass of the walls regulates the temperature.

“My home is built with 12” pine logs and easily outperforms “traditional” stick frame construction in efficiency. It stays warmer through the night and then cooler through the day as the significant mass of the walls regulates the temperature."

I couldn’t agree more…that’s why ours is not a traditional stick built. Our 2200 square foot home using traditional 2x6 FG plus 1" wall/ceiling envelope urethane foam board with reflective backing insulation under interior sheet rock. Though technically adding only R4 to the insulating value of 6" FG to R18, it insulates the studs from heat transfer, which is the big disadvantage of stick built. This makes it nearly twice as efficient in use. It uses less than 4oo gallons (one fill up with dual storage tanks) heating oil per year in central Maine. This includes heating hot water with NO aux. heat source. Log homes do make excellent homes with their thermal mass (“heat sink” was poor choice of words). They were my first choice until I did the cost benefit analysis of this construction. Neighbor followed suit with his new house of 3000 plus square feet and heating has shown similar savings/advantages where oil/gas truck delivery is non existing during most of the winter.

Wow, 400 gal is fantastic for your area. I’m on the MA/NH border and use about 3 cords of wood on average for the heating season. It’s 75-80 deg F most of the time.

You must’ve had a grin from ear to ear when oil hit its high last year or so. A Guy I work with put in geothermal last fall. His electric bill is miniscule. About 8 years ROI for him.

One disadvantage of real log construction is difficulty in making changes. Something I hadn’t considered beforehand.

Our first choice was always a log home. The necessity of our location and inability to get fuel oil/gas deliveries when needed forced this decision. It was a fight with the contractor too but he came through and did an excellent job.
BTW, we “live” with less than 70 degree temps inside midwinter and program much lower when not around. That plus activating different zones only on demand probably has as much to do with savings as the insulation. Geothermal was a thought, but that amount of water access at best is spotty around here.
IMO, wood heat and log homes are an ideal fit. But after 27 previous years of heating with wood in other home, I don’t want to see another wood fire except for atmosphere. We let guest “do their thing” down below overlooking the lake. We do the thermostat up stairs.

Oh boy, lots of action on my post!!! I used my old email for this forum, I’ll have to update it!