A fireplace damper is a fairly simple device which controls the flow of air through the chimney. The damper is actually a metal plate which can be moved to either open or close the chimney. The idea of these dampers is that they will help to retain heat inside the house instead of allowing it to escape up the chimney. The damper is only opened when the fireplace is in use, and it is needed to remove fumes.
Most dampers are controlled manually using a knob inside the home. This means that they are very simple and are things that can actually be made by yourself if desired.
Step 1: Buying Components
Start the project by buying all of the components that you need to complete the project. You will be able to make the steel frame and plate, or alternatively you can buy these in standard sizes from most chimney supply stores.
All of the other components are available at your local home hardware store. Just make sure you have everything you need before starting and you shouldn't have a problem.
Step 2: Fixing Hinges
The steel hinges should be fixed onto the steel frame by using the bolts and the ratchet. The hinges need to be positioned in the middle of the long section of the frame.
Step 3: Fixing the Plate
The plate then needs to be fixed to the hinges using the bolts so that it is free to move out of the way.
Step 4: Preparing the Chimney
Drill two holes into the chimney around 2 feet over the fireplace. Drill two more holes into the steel frame so that they can be used to fix the steel frame into the holes inside the chimney.
Step 5: Fixing the Damper
Fix the steel frame inside the chimney by screwing it into the brick work. Make sure that you are using long enough screws to firmly hold the damper frame in place so that it doesn't move when the chains are pulled.
Step 6: Sealing
The edges of the frame should be sealed so that there are no gaps. The easiest way of doing this is to use the high heat silicone around the edges. If you're not happy with the seal, you will find that cold air still manages to enter the house. In this case apply another coat of silicone.
Step 7: Connecting the Chain
Cut two pieces of chain the correct length to reach the top of the damper from the bottom of the fireplace. Then bolt each piece of chain on either side of the steel plate.
Step 8: Testing
Pull each chain to ensure that the damper plate will open and close as it should do.
The damper should be shut whenever you're not u sing the fireplace. This will prevent any debris and cold air entering your room by falling down the chimney.