High Lockout
E2222 on Worcester Bosch Greenstar Si Combi / i System

Your boiler has detected an electrical fault with the internal sensor that monitors water temperature, causing the system to shut down for safety.

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 sensor short circuit error

What causes this fault?

This fault occurs when the boiler's internal computer receives an incorrect electrical signal from the sensor that monitors the temperature of the water leaving the unit. The most common reason is that the sensor has suffered an internal electrical failure or the wiring connecting it to the main control board has become damaged or loose. Because the boiler can no longer safely verify how hot the water is, it shuts down to prevent overheating.

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

E9 224View →A7View →

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