Low
H29 on Worcester Bosch Greenstar 12i System

Your boiler is struggling to communicate with a weather sensor outside your home, so it is temporarily ignoring the outdoor temperature readings to keep your heating running.

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

Outdoor sensor defect (available when accessory outdoor sensor is connected)

Engineer required

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

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Related fault codes

H08View →

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