High
E2 233 on Worcester Bosch 30i Junior

Your boiler has lost its connection to the internal thermometer that measures the temperature of the water heading to your radiators, causing it to stop following your heating demands.

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 temperature sensor disconnected

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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