Photo of automatic flue vent damper (C) Daniel FriedmanGuide to Automatic Vent Dampers Oil Fired Heating Equipment

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Automatic vent dampers:

Here we explain Automatic flue vent dampers, what they are, how they work, and why they can save money on heating bills. This article series answers most questions about central heating system troubleshooting, inspection, diagnosis, and repairs.

We describe how to inspect, troubleshoot and repair heating and air conditioning systems to inform home owners, buyers, and home inspectors of common heating system defects.

We also provide a MASTER INDEX to this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need.

Automatic Vent Dampers on Heating Equipment Flues

Automatic vent damper, (C) Carson Dunlop AssociatesHeating costs can be reduced by any measure that makes sure that as much as possible of the warmth produced by burning a heating fuel (such as natural gas) is sent into the occupied space rather than lost elsewhere.

[Click to enlarge any image]

An automatic vent damper, such as illustrated in Carson Dunlop Associates' sketch here and in our photograph just below, reduces heat loss in buildings where gas-fired heaters are installed.

When the heater is off the electric motor turns the vent damper to the "closed" position so that heat is not lost from the boiler nor the building by natural convection.

When the heater is about to turn on, before the burner is ignited the automatic vent damper motor opens the vent so that combustion gases can flow freely through the flue vent connector and out of the building's chimney.

Don't confuse an automatic flue vent damper with two other "damper" devices: a heating system automatic duct damper or a duct fire damper.

Exactly what is an automatic flue damper?

Photo of automatic flue vent damper (C) Daniel FriedmanAn automatic flue damper is a device which closes the heating flue when the furnace or boiler is "off" so that we won't continue to lose building heat up the chimney - it's a device to reduce heating costs and save on heating oil consumption.

At left we show an automatic flue damper installed on a gas-fired heating boiler in Two Harbors, Minnesota. This is a Weil-McLain automatic vent damper model RGP-KSF / RVGP-KS. For this model the company specifies:

When the heating system has turned off at the end of an "on" cycle of burning fuel, the automatic flue damper electric (see sketch above and photo at left) motor turns a baffle inside of the flue vent connector pipe to a position "across" the pipe so that the airflow inside the pipe is blocked or stopped.

We define and describe in more detail the differences between automatic flue dampers, barometric dampers, fire dampers, and draft inducer fans at TYPES & MODELS of DRAFT REGULATORS

The articles at this website describe the basic components of a home heating system, how to find the rated heating capacity of an heating system by examining various data tags and components, how to recognize common heating system operating or safety defects, and how to save money on home heating costs. We include product safety recall and other heating system hazards.


Continue reading at BACKDRAFTING HEATING EQUIPMENT or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.




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