High
289 / CF on Worcester Bosch Greenstar CDi Compact

Your boiler's internal sensor that detects water pressure has lost its connection or has developed a wiring fault, preventing it from knowing if the system pressure is safe to operate.

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

Water pressure sensor not connected or short-circuit to ground

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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