Low
E83 491 on Potterton Promax 15 & 24

Your boiler's internal memory backup battery is running low, which means it may struggle to keep the correct time or save your heating schedule during a power cut.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

Programmer Battery

From this model's manual
Verified against the Potterton Promax 15 24 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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