High
1 flash green on Main Insul 7

Your boiler has shut down because the water inside is getting too hot, too quickly, or cannot circulate properly through your heating system.

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 protection: Maximum flow temperature exceeded, Flow temperature rise rate too high, Excessive difference between flow and return temperature

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

E160View →

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