Gas Heat Flue Economizer - Automatic Vent Damper System
The gas flue economizer or automatic vent damper closes off the top of this water heater after the burner finishes the heating process. The automatic flue damper traps heat in the furnace, boiler, or water heater and holds it in and around heat exchanger instead of allowing it to rise up the flue. The automatic vent damper is powered by the control voltage for the boiler. After the burners turn off and the noxious gases have been safely vented the automatic vent damper or gas flue economizer has a little motor that powers it to the closed position. All the heat is trapped inside the furnace, boiler, or hot water heater. Before this system came into to use all the heat around the exchanger or hot water tank was allowed to rise into the flue and vent to the atmosphere. With the automatic vent damper or gas flue economizer the heat remains inside the unit and this adds efficiency to the system by preventing the heat from escaping into the atmosphere. To prevent the burners from lighting when the damper is closed an end switch opens the circuit to the gas valve and ignition control (depending on the manufacturers specifications). If the burners were allowed to ignite with the automatic flue damper or gas flue economizer in the closed position then dangerous noxious combustion fumes would build up in the area where the furnace, boiler, or hot water is located and cause dangerous conditions for the occupants. Furthermore, the flames wouldn't burn correctly because the combustion gases wouldn't have a direct place to vent. If your furnace, boiler, or water is equipped with an automatic vent damper or gas flue economizer and it will not light a check of the automatic vent damper or gas flue economizer is warranted to make sure it is opening. A properly working automatic vent damper or gas flue economizer can save you in energy costs.
