The gas fireplace is associated with warmth, comfort, and beauty.
Unfortunately, these adjectives are left out the door when the fireplace stops working the way it should. This includes a situation where there is cold air coming from the gas fireplace.
Cold air comes from the gas fireplace when there’s a flue or air intake in the firebox. This is designed to maintain airflow but can lead to cold air coming in. To fix this, find the flue in the firebox, inspect the clamp, and remove it. Now close the flue to make sure air does not come in. Please note, there are building code regulations where the c-clamp is mandatory. Check this before making any changes.
This will ensure cold air does not come in through the fireplace.
This article will look at why cold air comes from a gas fireplace and how to fix it.
Table of Contents
Best Fireplace Screen For Cold Air (EDITOR’S CHOICE)
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How To Fix Cold Air Coming From Gas Fireplace
1. Turn Off The Gas
Before looking for a gas fireplace draft stopper, you need to turn off the gas to the fireplace.
This will ensure you can play around with the different components and fix this problem properly. If you don’t do this, it’s possible the cold air will continue to come in and you might endanger yourself during the process too.
To turn off the gas supply, there will be a valve near the bottom.
Turn it off and make sure it is on that setting before moving forward.
2. Find The Flue in the Firebox
You are now going to look for the flue in the firebox.
This is going to be located near the top of the fireplace and should be accessible if you take a flashlight to see where it is.
Since the area can be dark, you will require a light source while looking around.
Once you find the flue in the firebox, you will notice where the cold air is coming from. It will become obvious as most gas fireplaces are installed with one that has an air intake built into it.
If you didn’t know this, you wouldn’t realize where the cold air is coming from!
If the gas fireplace makes the house cold then it’s time to shut things down. You will need to get to the flue and close it off.
3. Remove The C-Clamp
So, how do you go about closing off the flue?
The first thing you are going to notice is a damper or c-clamp attached to the flue. This is designed to make sure the air intake is locked OPEN at all times.
Why does this happen?
In many states, strict building code regulations are stating the gas fireplace should not be sealed with indoor air. This means there has to be a locked OPEN air intake that allows for external airflow.
If this does not happen, it will not pass an inspection.
This is why any time a gas fireplace is installed in those regions, there is a flue in the firebox with the c-clamp in place.
You will have to read up on this for your region before making any changes.
If it is required, the next best option is to set up a fireplace cover that goes in front of the fireplace. This will shield the room from the cold draft.

4. Close The Flue
The last step is to close the flue assuming it’s legal to do so in your region.
You are going to want to close the flue with anything that seals the air from coming in. This is going t vary depending on the flue itself and how large it is.
Take your time, inspect the flue, remove the damper/c-clamp, and then move forward with a long-term solution.
Final Thoughts
These are the things to focus on when learning how to stop cold air from coming through the gas fireplace.
If cold air is coming from a gas fireplace, it’s likely due to the flue being locked open using a c-clamp or damper. This is to allow airflow from an external source. To fix this issue, read the building code in your region first. Some states require the air intake to remain open. If not, you can turn off the gas supply, find the flue in the firebox, remove the c-clamp, and stuff the flue to stop the cold air.
This will resolve the issue right away.
If it is illegal to do so, just buy a fireplace cover to block the cold draft instantly.
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