High
Water Circulation LOCKOUT on Potterton Suprima HE

Your boiler has shut down because it cannot move water around its internal system effectively, causing it to overheat for safety reasons.

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

Manual reset. Casting thermistor exceeds 80C four times, or flow direction is incorrect (casting thermistor higher than flow thermistor).

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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