Low
S.34 on Heatline Monza

Your boiler has detected that the external temperature is very low and has automatically turned itself on to heat the pipework and prevent it from freezing.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

"Frost protection" mode

Engineer required

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

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