High
E50 on Potterton Promax 15/2 HE Plus

Your boiler is struggling to accurately measure the temperature of the water it is heating, so it has shut down to prevent overheating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Hot water thermistor fault

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E20View →E28View →

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