Check list for wood burning appliances.

Check all gasket material, the bypass damper, and on cast iron stoves, the seams, once a year; replace frayed or worn material. Re-cement the seams as necessary.

Check the catalyst gaskets and the gasket that seals the bypass mechanism.

Hint: One way to test the tightness of a gasket seal is to close the firebox door on a dollar bill. Pull gently on the dollar bill. If it pulls easily out of place, the seal isn't tight and the gasket should be replaced. Repeat this test in several locations to check the seal all around the door. Gaskets in good condition will provide an airtight seal.
A poor seal around a catalyst bypass allows smoke to pass through unburned, thereby increasing pollution.

Check the wood-loading door and the ash drawer for tightness. These two areas are subject to warp or worn gaskets. Poor fit may result in over-heating or may allow smoke to escape into the room.
Make sure the thermostat (if your stove is equipped with one) is working properly; replace as necessary. Refer to parts list in your owner's manual. A broken thermostat can prevent air inlets and dampers from opening and closing properly.

Check the flue twice a month and have it cleaned at least once a year. After cleaning, check the seals and retighten joints in the flue and to the stove. Buildup of creosote on the flue walls can re-ignite and cause fires. Tight seals and joints prevent leaks. Replace firebrick and other insulating materials when you see crumbling or if pieces are missing.
These insulating materials are critical to your stove's heating efficiency and pollution-reduction properties. Don't remove or tamper with the preset operating or temperature controls because it's against the law, it will void your stove's warranty, and it will create a safety hazard. The stove will be less efficient and more expensive to operate.

Thermostats control either primary or secondary air, or both. Tampering may ruin the precisely designed secondary combustion capabilities, resulting in lower efficiencies, higher operating costs, and greater pollution.

Don't abuse your catalyst. Don't drop or scrape the catalyst, remove the metal band (if your model has one), or use high-pressure air to clean. Don't clean the catalyst with water when it is hot and in the stove. Catalysts can be damaged, thereby reducing their effectiveness.