Odd smoke drafting on 1940's fireplace

jmprobert

New Member
Oct 1, 2019
2
Minneapolis, MN
Hey everybody, I'm new here so hopefully I'm following the proper posting rules.

My wife and I moved into a 1942 Cape Code style home that has a fireplace and ash dump. We had it inspected before last winter to make sure it was safe to burn and we were given the green light from the sweep until we smelled smoke downstairs and it was a little hazy too.

We went down and realized the the clean out door had a crack in the flange so there was an air gap there you could slip your fingers behind.

It seems odd to me that some smoke would have gone down the ash dump instead of up the chimney.

Either way, I'm replacing the clean out door and looking at this unit.

2 Questions
1. Is it normal for smoke to go down the ash dump?
2. If this isn't the source, does anyone have suggestions of another place to look for the smoke entering the basement?

The other half of the chimney used to be for utilities venting up but that's since been capped off both in the basement and at the top of the chimney when new furnace and water heater were installed by the previous owners.
 

begreen

Mooderator
Staff member
Nov 18, 2005
83,648
South Puget Sound, WA
Do both flues terminate at the same height at the top of the chimney? If so, that is most likely your culprit and not the ash dump. Negative pressure in the lower fireplace room is sucking smoke down the adjacent flue. The cure is to raise the main floor flue up 12-18".
 

Ludlow

Minister of Fire
Jun 4, 2018
1,423
PA
He said the second flue was capped top and bottom.

Do both flues terminate at the same height at the top of the chimney? If so, that is most likely your culprit and not the ash dump. Negative pressure in the lower fireplace room is sucking smoke down the adjacent flue. The cure is to raise the main floor flue up 12-18".
Think maybe some hot coals are falling down the ash dump? Another possibility is that the water heater has a power vent and is drawing smoke down the ash dump.