Medium
34 on Alpha C25 Xtraflame

Your boiler has detected that a secondary heating circuit, such as underfloor heating, has become too hot and has automatically shut down to prevent damage.

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

Low temperature zone 2 safety thermostat operation

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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