Safety: Turn OFF power and gas before tightening any internal components.

Check wall mounting: Ensure the heater is firmly fixed to the wall using appropriate anchors. Tighten any loose mounting brackets.
Inspect fan: Check the fan for debris or damage. Replace the fan if the wheel is imbalanced.
Secure panels: Tighten all accessible screws on the front cover, internal baffles, and flue collar.
Flue support: Make sure the flue is properly supported and not transmitting vibration into the heater.

Water heater vibrates excessively or rattles during operation.

Possible Causes