High
2 pulses on Worcester Bosch 35 RSF

Your boiler is currently stuck in a testing mode used by engineers and needs to be switched back to its normal operating setting.

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

Check service mode switch is in minimum position

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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