The more you utilize your catalytic combustor, the more you protect air quality and recover heat from your woodstove. When new, a catalytic woodstove emits less than 4.2 grams per hour of pollutants into the atmosphere, while a non-catalytic woodstove approved by the Environmental Protection Agency is allowed to emit up to 7.5 grams per hour of pollutants. Except during cold start-up when you should bypass your combustor, always use the combustor to recover heat from your smoke and protect the environment.
After 12,000 hours of use, a combustor is expected to have lost 25% of its catalytic function. This is a natural process called “wear-out.” Molecules of platinum and palladium aren’t actually lost, but their binding to smoke pollutants that can’t be removed by maintenance means gradually your woodstove will recover less heat from the smoke. Gradually you’ll notice less warmth, and eventually you’ll see dark pollutants from your chimney. (White steam is a normal emission from any EPA-approved woodstove, and water vapor is a natural harmless byproduct of catalytic reaction.)
Conscientious owners replace their combustors after roughly 12,000 hours even if the combustor is intact. The payback from your additional heat recovery is well worth your cost. This USA winter weather chart helps you plan when to replace your catalyst.
If you live in Zone 5, Northern Indiana or Western Massachusetts for example, replacing the catalyst after two and a half seasons is cost-effective. A conventional ceramic 6-inch round CC-001 replacement catalyst, including the $12.50 shipping cost, costs $56 per season to use.
Upgrading to a STEELCAT will cost you $71 per season of use. A steel combustor heats up faster than ceramic and you can engage your combustor at a lower temperature, recovering more heat from your wood.