Low
b52 on Potterton Powermax HE

Your boiler is currently reheating the hot water cylinder and this message is a status update rather than a critical failure.

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

Indicative cylinder temperature. O.K. Cylinder being re-heated. Press RESET button to scroll display

From this model's manual
Verified against the Potterton Powermax He installation & service manual, page 39.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This message appears when the boiler's internal sensors detect that the hot water stored in the cylinder has dropped below the target temperature. It indicates that the burner has successfully fired up specifically to boost the water temperature back to your desired setting. It is a normal part of the boiler's operation and shows the system is working as intended to ensure you have hot water available.

DIY fix possible

Wait for the boiler to finish the reheating cyclePress the RESET button to scroll through the display and clear the messageCheck that your hot water timer is set to an 'on' period

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