Here’s what you need to know about your Chimney Dampers!

Here's what you need to know about your Chimney Dampers!
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When you’re not using the fireplace, the chimney damper keeps conditioned air from escaping via the flue. When you start a fire, open the damper to allow for appropriate ventilation and to let the smoke go.

A closed damper restricts airflow and poses a safety risk by allowing smoke to enter your home. Here’s how to figure out if the damper is open or closed.

What Damper Type Do You Have?

What Damper Type Do You Have?Chimney dampers are divided into two categories: If you’re not sure if your chimney’s damper is open or closed, start by defining the type of damper you have.

Throat dampers are popular because they’re convenient. A throat damper prevents cold air from entering your home by closing the bottom of your chimney.

Because the throat damper is integrated into the fireplace and visible at the top of the firebox, it’s simple to determine if it’s open or closed.

The neck, or upper section, of the firebrick that lines the rear of your fireplace, should slope towards the throat damper to channel smoke up and out while decreasing cold air input.

This damper, which is placed at the top of the firebox, swings down to close the throat when the fireplace is not in use. Most dampers are made of cast iron or steel and are black or rusted in appearance.

To open or close the damper, reach inside the fireplace opening and behind the lintel. You should be able to open or close it using a knob or rod (which is normally found on the front face of the fireplace) (located in the fireplace, above the firebox).

The chimney cap is sealed with a top-mount damper, which is an advantage over a throat-mounted damper because it keeps animals, birds, insects, and debris out of the chimney.

The top-mount damper is held open by a spring, and the control cable or handle is normally attached to the fireplace wall. The damper will be in the open position by default, and you will have to shut it by pulling on a chain or cable and working against the spring.

How to Determine Whether or Not the Damper Is Open

How to Determine Whether or Not the Damper Is OpenThe kind of damper you have will determine how to identify if it is open or closed. If you start a fire with the damper closed, your house will rapidly fill with smoke. For safety reasons, you should make it a habit to check if the damper is open before lighting a fire.

There are several techniques for determining if the damper is open or closed.

Feel around for a draft

An open damper allows air to freely move through the chimney flue. By moving your hand or face into the fireplace, you should be able to feel the cool air.

If you have a top-mount damper, this procedure is not failsafe. The presence of cold air in the chimney flue might make it appear as though the damper is open.

Visually inspect

A visual inspection is one of the most reliable methods of determining whether or not the damper is open. Simply immerse your head in the flames and raise your eyes.

The closed damper just over your head will impede your vision if you have a throat damper. You should be able to reach the closed damper if you reach up.

Check for daylight just at the top of the flue if you have a top-mount damper. The damper is closed if you can’t see daylight from the top.

Examine the controls

As long as you are familiar with the chimney and its controls, the present position of the controls (cable, rod, handle, etc.) can help you establish whether the damper is open or closed.

It’s preferable to do a visual check after glancing at the control location if you’re in an unfamiliar house.

If you’re not sure if the damper is open, don’t start a fire in the fireplace.

According to some websites, you can verify whether your damper is open or closed by simply lighting a fire in your fireplace. It is exceedingly risky to start a fire with a closed damper and should never be used as a test procedure.

When a damper allows smoke to enter a home, it can cause harm to the interior, valuables, and health.

Keep an eye on the flames and smoke, and open the damper as soon as you discover that the airflow is inadequate.

When you start a fire with a closed throat damper, smoke will instantly flood your house. If your chimney has a top-mount damper that is closed, smoke may take a few minutes to fill the house, but you will realize that there isn’t enough ventilation soon.

How to Open a Damper and Check the Controls

How to Open a Damper and Check the ControlsEven though you can feel a draft, it’s always a good idea to check the settings before lighting a fire because a partially open damper won’t allow for appropriate ventilation.

Various types of controls

Throat dampers typically feature a rod that you may push or raise to change the damper’s position (circled below):

Some chimneys have a knob that turns a rod to adjust the damper. These knobs are normally placed on the outside of the fireplace, positioned over the fireplace entrance but occasionally out to the side.

The spring-loaded design of top-mount dampers is used. They stay open until you close them and tighten the mechanism by pulling a chain or lever, which is usually situated on the side of the firebox.

The damper is open if the chain or handle is not tightly attached to the bracket.

What is the Best Way to Open a Damper?

What is the Best Way to Open a Damper?Check to see if you can push or lift the rod farther if you have a throat damper with a rod control within the fireplace. A knob control on the fireplace’s outside might be more difficult to use since you may not know which way to turn it.

There is a straightforward solution: to verify the damper position, turn it all the way in one direction and insert your head into the fireplace. If the knob has no index marks, it’s a simple method to figure out which direction shuts and opens the damper.

If you have a top-mount damper, pull down on the chain to see if you can close the damper. If you don’t secure the chain, the damper will quickly spring back up. It’s also a good idea to do this before lighting a fire to make sure the top-mount damper is fully open.

As you get more familiar with your chimney, you’ll be able to determine whether a damper is open or closed. Once you’ve become acclimated to the chimney and what a draft from the flue feels like, you should be able to detect if there isn’t enough airflow.

When you’re not using the fireplace, remember to close the damper to conserve your home’s conditioned air.


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