Medium Warning
1-2-3 on Remeha Gas 350

Your boiler has detected a general issue that needs checking to prevent a full breakdown.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

General warning signal

What causes this fault?

This fault occurs when the boiler's internal computer detects an inconsistency in the electrical signals required to keep the system running safely. The most common reason is that the components responsible for lighting the flame or monitoring its presence are beginning to wear out or are sending weak feedback to the main control board.

DIY fix possible

Check that your home's gas supply is activeEnsure the system water pressure is between 1.0 and 2.0 barRestart the boiler by holding the reset button for two seconds

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