High
2921 on Worcester Bosch Greenstar 8000 Style

Your boiler is currently stuck in a technical testing mode used by engineers during setup and is not operating normally to heat your home.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Boiler electr. in test mode

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

2922View →2923View →

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