High
30. on Remeha Quinta 30

Your boiler has switched itself off because the water inside is not circulating correctly, causing a significant temperature difference between the water heading to your radiators and the water returning to the boiler.

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 temp. Difference between flow and return 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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