What is a Fireplace / Chimney Damper & Is It Important to Chimney Function?

For a fireplace to operate safely and efficiently, its components must all be fully functional.  The fireplace/chimney damper is important to chimney function all year long, whether the fireplace is in use or not.  Here are a few things you should know about dampers.

What does a damper do?

Dampers are usually made of metal and work like sealing flaps to regulate how much air passes between the firebox and the chimney.  The damper should be opened when there is a fire and closed afterward to prevent outside air from coming in and inside air from going out.

Where is the damper located?

Typically dampers are installed just above the firebox, right under the flue.  Sometimes dampers are mounted at the top of the chimney.  Dampers are opened and closed with a convenient handle attached to a pulley system.

The importance of fireplace/chimney dampers

As we mentioned, dampers control air flow.  When air inside the home is warm and a fire is not going, the damper keeps this warm air from escaping up the chimney while preventing cold outside air from entering the home.  It works the same in warmer months to prevent cool, air-conditioned air from being lost and hot outside air from coming in.  When the fireplace isn’t in use, it’s important to remember to keep the damper closed.  If you build a fire with a closed damper, it won’t take long for you to realize this when smoke starts billowing into the house.

Aside from controlling air flow, dampers also keep unwanted “things” from the outside from getting into the house.  This includes water from a leaking chimney, small animals and any kind of debris that might find its way into the chimney.  (Assure children that dampers won’t hinder Santa Claus!)

Can dampers wear out or be damaged?

The answer is yes and yes.  Over the years and with regular use, dampers can become warped, and it doesn’t take much warp to lose your air-tight seal.  Sometimes you can hear air hissing through a compromised seal, signaling the need for replacement.  A rusted damper is a sign that water is entering the chimney.  Rust can be cleaned off a damper, but this means you need to have your chimney looked at by a professional.

The pulley system also can wear out after much use, preventing the flaps from opening or closing.  You’ll know when this happens, and you can have a new one installed.

Like with a vehicle, basic use won’t always tell you when there’s a problem or when a problem is on the way.  Fireplace experts everywhere recommend annual inspections and cleaning to keep your system running properly and safely.

Hudson Valley Chimney of Poughkeepsie provides a full range of professional chimney sweep services.  If your fireplace components haven’t been looked at for a while or if you believe maintenance or repair work is needed, call us at (845) 471-1071.  We’re happy to schedule an appointment and answer any questions.