Weil-McLain water heater makes rumbling, popping, or kettling noises during heating.

Safety first: Turn off power and allow the unit to cool before touching piping or opening any drains.

• Bleed air: Use air vents or purge valves to remove trapped air from the water heater loop. Air can cause localized boiling and noise.
• Check flow rate: Ensure circulator pumps are operating and valves are open to provide adequate flow through the heat exchanger.
• Descale if necessary: In hard water areas, professional chemical descaling of the heat exchanger or tank coil may be required to remove lime deposits.
• Verify firing rate: Have a technician confirm that the burner input is correctly set per Weil-McLain specifications.