High
18. on Remeha Quinta 30

Your boiler has switched itself off because the water inside it has become dangerously hot, likely due to a blockage in the system or a pump failure.

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

Max. water temperature. Flow temperature too high.

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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