High
8/2/5 on Worcester Bosch GB162

Your boiler's control system is confused because two different control panels are trying to act as the 'boss' at the same time.

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.

What the manual says

Manufacturer manual

Conflicting addresses. Both RC25 and RC35 are registered as Master.

From this model's manual
Verified against the Worcester Bosch Gb162 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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