Outdoor wood boiler conversion

[Larryjbjr]

OK, I just found this forum yesterday. I’ve done a little searching and looking but cannot find exactly what I am wanting to do.

So here are my thoughts.  I have an outdoor wood boiler that I have been heating my house with this winter using just strictly wood.  But I got this idea of possibly using waste oil to help cut back on how much wood I use.

 I was thinking of just taking a 55 gallon drum of motor oil and pumping it directly into the firebox whenever the boiler calls for heat. My original thought was just to simply have a metering system so that it would simply spray about a half a gallon of oil onto the wood in order to help get the fire burning quicker.  But after talking to some friends I thought there may be a way that I could actually convert the wood boiler into a waste oil/wood boiler.

 I was thinking kind of a hybrid system where I would continue to burn wood and  simply spray oil into the firebox when it was calling for heat. But I’m not sure if that would even work. Or how it would work.

 I figure I can get about 500 gallons a year of use motor oil from my employer. They also have Synthetic hydraulic oil, but my boss doesn’t think that would work for a waste oil burner.

 So I guess I have two questions right now.

 First of all, would synthetic hydraulic oil work for a waste oil burner?

And also, does anyone have any suggestions on how to use my outdoor wood boiler to also burn waste oil?

I’m sure there is a way to convert the outdoor wood boiler to burn only waste oil. But at this point I’m not interested in doing that. Simply because I don’t know if I could get enough waste oil to heat my house. But also because I think that would probably cost more money than I’m willing to put out right now.

[Nubs]

Hey, i'm new here also. i have done a dual burn outdoor water boiler in the past, starting on a new one now. its very doable but the only way i found to do it with low hassle, safe and reliable is to run a converted oil burner gun and enclose the front of the boiler to store the feed oil and burner @ around 40 degrees or more.
Any kind of drip system is to hard to control with temperature change in my opinion, I have seen 2 drip wood boilers run away and it will cook the life right out of them. If you try to control and or back down the burn rate with the damper if it does get away the unburnt  gases becomes pretty flammable and if you don't choke it off 100% and let it cool down it can reignite and blow the door right out of your hand if it does .

[Larryjbjr]

run a converted oil burner gun 

Care to elaborate on this? What is a converted oil burner gun?

the unburnt  gases becomes pretty flammable and if you don't choke it off 100% and let it cool down it can reignite and blow the door right out of your hand if it does .

I didn't realize that waste motor oil gases were that explosive. I assume you are still referring to a drip system.

What about an idea to just spray oil into the firebox when calling for heat, and limit that to, say, 1/2 a gallon and then shut the oil pump off?

I see that waste motor oil has about 140,000 btu/gallon. Now, is that only if sprayed in a fine mist? Or, can I expect those kind of btus by just spraying the oil onto the burning wood?

I'm still trying to understand this whole thing.

[Nubs]

When the oil gets hot and turns into vapor is when it can become a problem, just something to keep in mind.

This is what i have been running for about 8yrs now, last few yrs its been in a radiant forced air unit inside the shop. there should be threads here that explains how they work, i think it may be more involved than what your looking for though.
 

[Nubs]

I will try to go into more detail when i get some more free time but i don't think its what your looking to do.

[u1100l]

Waste oil is liquified tires.  Make it easy and start slicing up some Goodyears.

[Oilburner]

A " Hybrid" wood burner would work.
You could NOT just dump an amount of oil every so often. The oil would want to flash to vapor and there would not be enough air and the thing would smoke like a bitch and then probably over heat the boiler before dying down to nothing again.

The way to do it would be to Pump the fuel in a controlled and relatively constant manner. If the thing has a thermostat, then trigger  an amount of oil when heat is required and shut off when not.

You do not need ( or probably want) some superfine mist, anything that is better than a direct stream would be fine. A bit of flattened copper tube would be fine.  Spraying the oil on the coals/ wood will do the rest.

I would use either a Diaphragm pump like the little 4l/hr caravan type water pumps or the larger fuel pumps.  A gear pump would be good but I have not yet seen one capable of handling oil with any longevity. I make my own pumps using engine oil pumps and scooter motors and I literally pump 10's of thousands of liters with them over years without problem.

You could have 2 or more squirters on the pump to spread the oil around on the fire and just " tune" the output to the firing rate you wanted.

If you wanted to do away with the wood all together, just build a forced air type burner and it it in the fire box of the boiler.  I'm doing one for a spa heater and it will simply be a 2 Step. Idle when heat is not requires and ramp up to full power ( whatever I set that up at) and then back to idle.

[u1100l]

What is "idle"