Why does my water heater closet smell bad?
Foul and musty odors in a water heater enclosure often stem from unmanaged maintenance like a neglected tank or tiny, hard-to-detect gas leaks around the pilot valve. Because the heater itself may run perfectly fine, finding the exact source becomes difficult and prevents homeowners from safely clearing out the persistent stench.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Getting the system inspected by a professional
- 2Flushing the water heater
- 3Checking for issues with nearby AC units, drainage pans, or combustion chamber seals
- 4attempting to use a dryer duct to draw the gas out the flue
- 5calling a landlord's plumber or a technician
- 6calling the gas company
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“Every time I pass by the closest with the tankless water heater it stinks, it's a very foul smell.”source ↗
“Not sure what's causing the smell and how to get rid of the smell, water heater works perfectly fine.”source ↗
“It's a musty pungent smell. Not sure how else to describe it. I honestly don't know the last time it was flushed, we just moved in.”source ↗
Where this came up
People with this problem also raised
- 6Burning smell coming from HVAC vents
- 2Why does my washing machine smell musty even with the door open?
- 29Why does flushing one toilet pull water out of another?
- 2Why does my hall closet smell like cat pee on certain days?
- 4Why does my diaper pail still smell so bad?
- 12Why is my AC air handler wet and smelly?