Otherwise the flue may be blocked.
Chimney cleanout door installation.
Flanged frame for masonry installation 10 2 x 10 2 door measures 8 x 8.
Birds could have made nests there or parts of the chimney could have collapsed.
Installing a cleanout door on the outside of your chimney gives you clear access to the bottom of the chimney to remove ashes and soot.
8 x 8 cast iron chimney clean out door with flanged frame for masonry installation.
Adding a chimney cleanout door requires cutting the opening and installing a manufactured door that s designed to prevent cool air from entering the chimney.
Typically a cleanout opening is near the bottom base of the chimney.
This metal chimney vents an oil fired heating boiler.
Here shown during installation you can see that this metal chimney includes a removable cleanout door at the bottom of the tee used to turn from horizontal to vertical in the chimney run.
Use a mirror to inspect the interior of the cleanout door and flue.
The horizontal tee connects through the wall to a boiler on the other side.
If i had hired a pro to provide and install a door it would have cost at minimal three times or more than what my investment was by doing it myself.
The doors are available through online.