registre à commande

CONT: With conventional gas furnaces, little can be done to prevent losses of heated house air up the chimney when the furnace is firing. What can be prevented, though, is the loss that occurs when the furnace is not firing. A positive vent damper consists of a tight-fitting hinged damper door mounted in a steel collar and fitted into the flue pipe just before the pipe enters the chimney base. A fail-safe interlock switch prevents the furnace from firing unless the damper is completely open. This device may also be used with propane furnace.