- Observing flames on the exterior of a boiler (known as flame rollout) is a severe safety hazard. You should:
- Shut off the fuel supply immediately.
- Turn off the emergency power switch or thermostat to cut power to the unit.
- Evacuate the area or building if the fire is spreading or cannot be easily contained.
- Call 911 if there is an active fire.
- Contact a certified HVAC professional to identify the underlying cause before attempting to restart the boiler.
- Flame rollout is typically caused by a restricted flue/vent, a blocked heat exchanger, improper gas pressure, or inadequate combustion air.
- Could you tell me a little more about what you’re seeing?
- Where exactly are the flames escaping from (e.g., the burner door, the venting, or near the exhaust)?
- What type of fuel does your boiler use (gas, oil, or wood)?
- Has the boiler received regular maintenance or cleaning recently?
