Patricia Appelbaum is in the market for a new wood-burning stove, one without a catalytic element, to provide mostly supplemental heat for her 1,600-square-foot home. There are a lot of models to choose from, and that’s part of the problem.
“We understand that a non-cat stove needs a minimum temperature of around 500 degrees for an efficient secondary burn,” she says in a post in GreenBuildingAdvisor’s Q&A forum. “But we would like to have enough capacity to heat the whole house occasionally if necessary.”
Appelbaum’s family already has an older wood stove, a large model, that some people in the family like to run at a lower-than-optimum temperature. Before buying a new stove, she’d like to know whether having one with a smaller firebox would make any difference.
That’s the topic for this Q&A Spotlight.
A small, hot fire is best
A fire that burns quickly and intensely is the most efficient kind because it produces the most heat per unit of fuel, and also the least amount of air pollution, GBA senior editor Martin Holladay says. Hot fires also produce less creosote than low, smoldering fires that are starved for air.
“Going to a stove in the 50,000-55,000 Bth/h range can still work for a house with a ~25,000 Btu/h design heat load, but try not to go beyond that,” advises GBA reader Dana Dorsett. “Once the stove is up to temperature, it will still burn cleanly when throttled back to ~25% of its rated fire, which isn’t going to roast people out very quickly.”
The thermal mass of a stove becomes an important factor when the stove is used only intermittently but at high temperature, he adds. But there’s a caveat — when the output of the stove is…
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