How to Fix / Troubleshooting

Safety first: Turn off power and allow the heater to cool before bleeding air or opening pipework.

Restore proper flow: Clean filters and baskets, open all valves fully, and ensure bypass valves are correctly set.
Bleed air: If bleed points are provided, release trapped air from the heater and nearby high points in the system.
Descale elements: Inspect and descale or replace heavily scaled titanium elements following Elecro guidelines.
Check pump sizing: Ensure the circulation pump is correctly sized and that motorized valves are not slamming shut, causing water hammer.

Persistent banging indicates a serious flow or scaling issue that must be corrected to avoid damage.

Heater makes loud banging or knocking noises when heating.

Possible Causes