High
2964 on Worcester Bosch 1000

Your boiler is struggling to pump water through its internal system effectively, which is likely preventing it from producing heat or hot water.

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

Flow rate in heat exchanger too low

What causes this fault?

Circulation fault

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

224View →227View →

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