How to safely handle a carbon monoxide leak from a furnace
Carbon monoxide leaks from heating equipment require immediate professional intervention rather than temporary DIY patches like furnace cement. Trying to plug the leak yourself or guessing what the monitor numbers mean prevents you from safely addressing the danger and protecting your family.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1turning off the gas to the water heater and furnaceDid this help you?
- 2patching with furnace cement or mortar mixDid this help you?
- 3installing carbon monoxide detectorsDid this help you?
- 4Taking the detector outside to test if the reading drops back to zeroDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“All of a sudden it’s 004. I know that’s small but should I check for something specific? I know nothing about carbon monoxide.”source ↗
“mine did the same thing after a couple years, crept up to 003 then 005 out of nowhere.”source ↗
Where this came up
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