Low
H13 on Worcester Bosch Greenstar CDi Compact

Your boiler is simply reminding you that it is time for its annual safety service as programmed by your installer.

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

A time has been set in the Service interval function i.e. 1 to 72 months and that time has expired.

Engineer required

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

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