Mains light Low

Potterton Mains light Fault Code

Also written as MAINSLIGHT — same fault.

The Potterton Mains light fault code means: your boiler is receiving power as normal and this light simply confirms it is switched on, not indicating a fault.. It appears on 2 Potterton models in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: Indicates that the mains electricity to the boiler is on.

DIY fix possible

Check your central heating thermostat or timer settings if you are not receiving heat or hot water.If the boiler is working correctly, no action is required as this light is a normal indicator.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Potterton models that show the Mains light fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Potterton Mains light fault code information on this page is sourced and cross-checked against the official Potterton service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026