High
2956 on Worcester Bosch 1000

Your boiler has detected that water is not circulating correctly through its internal heating unit, preventing it from producing heat safely.

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

Hydraulic configuration at the heat exchanger activated

What causes this fault?

Configuration mode active

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

2955View →2957View →

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