High
Water temperature too cool on Worcester Bosch 24si II

Your boiler is struggling to reach the temperature you have set because it is not receiving enough gas or is failing to detect the water flow correctly.

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

Low gas pressure. Pot P1 not turned up. Stiff/sticking gas valve. Stiff/sticking flow sensor. Board 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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