High
é1 on Remeha Avanta Plus 28c

Your boiler has reached an unsafely high internal temperature, likely because there is not enough water flowing through the system to carry the heat away.

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.

What the manual says

Manufacturer manual

Flow temperature is higher than the set maximum temperature. Insufficient water. No through flow. Too much air in the system. Deviation in the flow or return temperature sensor.

From this model's manual
Verified against the Remeha Avanta Plus installation & service manual, page 50.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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