Oil sprays or drips into the chamber without lighting, vaporizes, then ignites all at once. Typical causes are delayed ignition from worn electrodes or a weak transformer, a nozzle that drips after shutdown, or a blocked flue that holds unburned vapor in the chamber. A bad puffback can coat a whole house in soot and blow the flue pipe apart.
Customer had a puffback last night, soot on every wall, check electrode gap and see if the pump's cutoff is dripping.
Also heard as
- puff back
Related terms
Light-off
The moment a burner ignites, and also the verb for lighting it.
Nozzle
The precision tip on an oil burner that atomizes oil into a fine cone-shaped spray, rated in gallons per hour.
Sooted up
Coated with soot on the fire side, from rich or poor combustion, so heat transfer and draft suffer.
Purge
Blowing air through the furnace and flue before ignition or after shutdown to clear out unburned fuel.