High
é2 on Remeha Avanta 28c

Your boiler has detected that hot water is flowing in the wrong direction or is blocked, which usually means the system lacks enough water or has trapped air preventing a proper flow.

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

Return temperature is higher than the flow temperature. Insufficient water. No through flow. Too much air in the system. Sensors not wired correctly. Deviation in the flow or return temperature sensor.

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

E4View →E6View →

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