High
OTHER FAULTS on Worcester Bosch 24i/28i Junior

Your boiler is struggling to control its internal temperature correctly, causing it to shut down to prevent overheating or inefficient operation.

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

FAULT POINT F. Primary water too hot (over 85°C) or too low (less than 75°C). Possible causes: thermistor/heat paste fault, low gas pressure, blocked flue/heat exchanger/burner, or gas valve sticking.

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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