I'm just curious if anyone has seen a loss in effeciency after installing a cold air line for the combustion blower?
Thanks
Using Cold Air for Combustion
- Freddy
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- Location: Orrington, Maine
- Stoker Coal Boiler: Axeman Anderson 130 (pea)
- Coal Size/Type: Pea size, Superior, deep mined
With an oil boiler they claim it's more efficient.... the cold air is more dense and helps the burn and, you are no longer using air from inside the house.
- coalkirk
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Should be just the opposite. Your house doesn't like a vacuum. If you use conditioned air from your home to burn coal (or oil, gas, wood) that air has to be replaced. Air gets sucked in around windows, doors, exhaust fans, anywhere it can find a pathway from outside. Then that cold air has to be reheated. Outside combustion air is the way to go. That's how 90% gas condensing furnaces get their 90% efficiency rating. They use outside air.traderfjp wrote:I'm just curious if anyone has seen a loss in effeciency after installing a cold air line for the combustion blower?
Thanks
Well your temperature *rise* would be the same when you tune for best combustion. Your inlet air is colder, so your stack/combustion temp is lower. In an oil burner application, you need to retune with a combustion tester so you do not have excess air which will waste energy.
Pluses would be you will never have to worry about a too tight house. Minuses would be that in an oil burner application you might get less atomization and thus more soot (smoke). In a coal application there is probably no down side, you want to keep the grates cold.
Pluses would be you will never have to worry about a too tight house. Minuses would be that in an oil burner application you might get less atomization and thus more soot (smoke). In a coal application there is probably no down side, you want to keep the grates cold.