«Previous    Next»
Simple Hot Air Wood Furnace
Richard Ackerman, Columbia, S. Dak., recently sent FARM SHOW photos of an inexpensive outdoor "hot air" wood furnace he built out of an old wood stove.
"We lost our house to a fire and moved into an older house until we could rebuild. However, the propane heater in that house did not work well and was expensive to operate, so I decided to build my own hot air furnace," says Ackerman.
He mounted an old wood stove on a platform outside the house and built a sheet metal housing around it. He fitted the housing with a squirrel cage fan and ran two big pipes to the house. He insulated the stove with 8 in. of fiberglass and ran a metal rod into the house so he can work the stove's damper from inside.
"It doesn't take up room inside the house, and all the mess and smoke stays outside. The only disadvantage is that I still have to go out in cold weather to fill it with firewood," says Ackerman. "It's insulated so well that I don't think we lose any heat to the outside.
"I plan to build a new furnace based on this design for the house we're building. We'll locate it farther away from the house so we won't be able to hear the fan, and put a small shed around it. I made a thermostat out of strips of copper and a strip of steel. It regulates the fresh combustion air so we can fill the firebox full without it śrunning away.' Last winter I filled the firebox with wood at night in 20 below zero weather and it was still going the next morning."
A problem with this type of stove is that if the electricity goes off and the fan quits, the stove will overheat. "I put extra large pipes on the stove - 14 and 11 in. dia. - so if the fan ever quits, warm air will still circulate inside the house. I put a regular furnace filter on the cold air pipe and two air cleaner filters on the heat pipe."
Contact: FARM SHOW Followup, Richard Ackerman, 12730 Tacoma Loop, Columbia, S. Dak. 57433 (ph 605 225-3231; email: bhalvorson@nvc.net).

  Click here to download page story appeared in.

  Click here to read entire issue

To read the rest of this story, download this issue below or click here to register with your account number.
Order the Issue Containing This Story
2004 - Volume #28, Issue #5