High Lockout
Fault 56 154 on Worcester Bosch Greenstar CDi Compact

Your boiler's internal pump has been manually overridden or is stuck in a manual operation mode, which is preventing it from working automatically 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

Pump (PE) operated manually.

What causes this fault?

This fault usually occurs when the boiler's internal pump has been set to run at a fixed speed or manual mode during a service or repair, and it hasn't been switched back to automatic control. It can also be caused by a communication failure between the boiler's main brain and the pump, or a physical blockage that forces the pump to behave abnormally. Without the ability to adjust its speed automatically, the boiler shuts down for safety to prevent overheating.

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

C1View →C7View →H11View →

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