I own a Charmaster Chalet wood burning furnace. It has a thermostatically controlled air draft control to regulate the heat output of the furnace. The control works by thermostatically adjusting the position of the draft door, thereby allowing more or less combustion air into the firebox as needed. The unit was purchased in 1987, and this fall the module that mechanically adjusts the position of the draft door failed. The part is not repairable. Do you know of any source of repair parts for Charmaster furnaces? I believe that the company is no longer in business. If you can offer any help, email me at email@example.com.