There doesn t appear to be any visible source of a leak from your pix.
Chimney cleanout door leak.
The mudcap may be compromised.
Use a plumber s putty or even play doh to build a dam on the floor around the cleanout door area.
It s always below the chimney but it s usually in your utility room.
There could however be a problem in one of three areas.
I would say to get on a ladder take a look at the top of the.
What this is the metal door that is usually in your furnace room.
It has an angled top to shed water and it overhangs the brick to keep drips off the chimney sides.
The chimney crown is the cement part on top of the chimney.
Soot creosote chimney fragments can accumulate so.
Open the chimney cleanout door inspect the chimney base masonry chimney fragments falling from above see masonry fragments debris at the cleanout signs of heavy creosote deposits a completely blocked cleanout by decades of fallen debris.
The crown of a masonry chimney is a concrete top that ideally looks something like the one shown.
You can see that the very purpose of the chimney crown is to keep rain out.
On 2018 08 05 by mod replacing the chimney cleanout door replacing the chimney cleanout door assuming it is on the inside of the building would not explain a water leak problem through the chimney into the building unless in the course of replacing the door someone pounded on masonry and cracked or broke the chimney walls.
2 many chimney leaks are from cracks in the chimney crown.
Jsotola feb 21 18 at 23 22.
One of the most prevalent calls that we get is water coming in the hatch which is the actual clean out for your chimney.
He inserted a plastic hose and ran over to a floor drain.
The water penetration is coming in through the ground.
The metal chimney cap may be too small for the flue tile or 3.
The bricks go up around the tile flue liners but at the top you need something to stop the rain and snow from just falling in around the tiles.
A homeowner drilled a hole into the chimney pit about 4 inches below the metal clean out door and into the water sitting in there.