Propane boiler making puffing exhaust noise in extreme cold
When temperatures drop significantly and multiple zones call for heat, propane boilers can develop a rhythmic puffing exhaust noise that may escalate into a loud whistle. This issue can persist even after replacing the fan and cleaning the unit, forcing homeowners to shut the system down manually.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
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Propane boiler making puffing exhaust noise in extreme cold
- 1Replacing the fan and cleaning the unitDid this help you?
- 2Shutting off the boilerDid this help you?
- 3Replacing the circulatorDid this help you?
- 4Calling a qualified repair personDid this help you?
- 5Pulling the damper forward a bit to prevent it from getting hung upDid this help you?
- 6Squeezing the sides of the opening so the plate stops rubbing on the bottomDid 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.
“Boiler (Lochinvar) making puffing noise from exhaust. Only happens when its super cold and both zones (2 zone system) are calling for heat. Fan has been replaced and unit cleaned, yet issue remains.”source ↗
“Made this noise for about 20 minutes at which point became a loud whistle and I shut it off.”source ↗
Where this came up
People with this problem also raised
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- 3Cylinder misfire and white smoke from exhaust
- 6Why does my HVAC condensate pump sound like a jet engine?