High
Failure at point K on Worcester Bosch 24CDi BF

Your boiler is not detecting when you turn on the hot tap, so it isn't starting the process to heat your 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

Domestic Hot Water Mode: DEMAND indicator does not illuminate or pump does not run. Checks include flow rate (> 2.6 litres/min) and flow switch functionality.

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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