Is Your Chimney Damper is Opened or Closed?

Many homeowners know their chimney damper, aka fireplace damper, needs to be opened before starting a fire but don’t know how to tell if the damper is open or closed. When we get calls about dampers at Magic Mountain Chimney Sweeps, we are always happy to provide answers. Dampers are, after all, a crucial part of fireplace safety. Learn all about fireplace damper basics below.

What Does a Fireplace Damper Do?

Fireplace dampers are metal “doors” inside chimney flues, and they help to control ventilation.

Read on to learn details about the important functions of dampers:

• Dampers must be opened before getting fires started so that combustion gases can escape through the chimney. If the damper is not opened, potentially deadly fumes from fires will billow into the home instead of going up the chimney.
• When a fireplace is not in use, the damper should be closed to operate as a “seal.” Otherwise, cold air will enter the home. Although heat rises, cold air sinks in the direction of the gravity pull. With an unsealed chimney, utility costs will typically spike because air warmed by central heating in winter will go up the chimney instead of staying inside the home.
• It is important that a damper is in good operating condition so that air cannot freely pass through the damper doors when they are closed. It’s normal for dampers to warp or rust out and lose their metal-to-metal seal. Contact Magic Mountain Chimney Sweeps if you are unsure about the effectiveness of your damper or conduct the following simple test with your standard throat damper:
• Place a dollar bill between the two doors of the damper as it closes. If the damper grips the dollar bill all the way across, your damper has a sufficient seal. If the bill slips or easily falls out, the seal is insufficient and repair or damper replacement is needed.

How to Open and Close Your Damper

There are two types or locations of dampers. Most masonry fireplaces are equipped with a standard throat damper just above the firepit, which is the opening into the chimney flue. You may, on the other hand, have a top-mount damper, which is located at the very top of the chimney flue.

How to Open and Close a Throat Damper

There are two basic ways to open and close a throat damper. Your damper may have a ratcheting lift or push rod that you push up or pull down. Typically, to open the damper, push up or lift the rod all the way. Pull it down to close the damper.

Another type of damper is a screw-type or rotary control damper. Typically, you will close the damper by turning it counterclockwise all the way, which causes the rod to hang down low. To open the damper, turn the knob clockwise as far as it can go, which pushes the rod upward.

Top-Mount Chimney Damper

A chain or cable is used for top-mount chimney dampers. Typically, you will release the chain or cable, which should result in the damper springing up to an open position. Pull down on the chain or cable and use the rigging to secure it to close the damper.

Magic Mountain Chimney Sweeps

For top-quality chimney maintenance services, including damper repair and replacement, contact Magic Mountain Chimney Sweeps. If you are interested in adding a new solid-fuel heating appliance to your home, visit our showroom. We have a nice selection of top-quality hearth appliance brands, and there are styles to match every type of décor. Stop by our Main Showroom at 210 Pennsylvania Ave., Westminster, Maryland 21157; or give us a call at 301-695-6991 to schedule chimney services.