How to Install a Boiler Vent Damper

What You'll Need
Boiler Vent Damper
Wire Cutters
Vacuum Cleaner

You can improve the efficiency of your boiler by installing an in-line vent damper. These are used to automatically shut off the vents to your boiler when they do not need to be open. By shutting off the vents when the boiler is not firing, you can help retain heat inside the house. As long as you can access the duct work, you can easily install a boiler vent damper. A vent damper will typically only cost a few hundred dollars to install but it will offer many benefits. It should pay for itself many times over in the first year alone.

Step 1 - Cleaning

If there is any dust is on the surface of the vents or ducts, this can make installing the duct dampers very difficult. It will also make controlling the air flow much easier. Use a vacuum cleaner to clean out the inside of the ducts.

Step 2 - Type of Damper

Most modern dampers are automatically connected to your boiler, this means that a small electric motor will open and close the damper. Check that you are installing a boiler vent damper which is suitable for use with your boiler and can be controlled automatically.

Step 3 - Measuring the Duct

Measure the size of the duct so that you will be able to choose a vent damper that will be a good enough fit. You will not get enough control out of a loose-fitting vent damper because air will escape around the gaps between the fans and the damper.

If you are interested in temperature control, find a boiler vent damper that offers this feature.

Step 4 - Check Location of Damper

Check that the proposed location of the damper will be ok without being a danger. If there is any water source in line with the damper then you will need to check that it will actually be able to fit.

Step 5 - Safety

When installing the vent damper you must ensure that the electricity is switched off. Add on an extra switch to your vent damper so that it's possible to easily shut it off the power whenever you need to perform maintenance. If you're wiring the damper directly into your homes breaker box then an individual circuit breaker might be a good idea, this will make it much easier to shut off the power when needed.

Step 6 - Attaching the Damper

Now the damper needs to be fixed to the inside of the duct. This can be done by using sheet metal screws which are typically included with the damper. Ensure that the damper is securely fitted to the duct so that it cannot move.

Step 7 - Connecting Power

Once everything else is complete it's just time to connect the power to the electric motor which will control the opening and closing of the damper. If you don't feel confident doing this by yourself then you might want to consider hiring a professional electrician to do this for you.