[cstreit]

I built a furnace similar to mothers for my shop. in 2006 my heating costs (electric is my only other alternative) were $800. In 2007 after building the heater the cost was $125.

...and old timers trick is drip-feeding waste-oil into wood stoves for shop use. I wouldn't do it in the home. Too messy, too hard to clean. THere is a fair amount of soot that will settle in your chimney. I use a t-pipe to make cleanout and settling easy.

Cost me about $150 to make, 90% of that cost was the insulated flue. I used an old water tank and a big aluminum dish. (Mothers improved design).

However this year I am going to spring for a commerical unit (though still drip feed). Why? If the oil-feed gets out of hand, things can go back quickly. I had a needle valve get slightly jammed with crud and the adjustment went out. I opened it further. When the jam cleared too much oil got in, drip pan overflowed and the stove temp spiked to well over 1200 degrees from it's averate op temp of 600-700. It got scary. I slammed the intake damper and all was well... ...but had I stepped out for 10 minutes? Oi! The commercial units have thermo controls, overflow protection, and other safety items that a homemade solution will not. Too much $ in my shop to risk it, good experiement though!