High
E32 on Potterton Promax 15/2 HE Plus

Your boiler has detected that the water temperature difference between the flow and return pipes is too great, meaning the system is struggling to move heat efficiently.

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

Temperature differentiation fault (flow/return)

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 →E50View →

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