High
31 on Johnson Starley Optima E20

Your boiler has detected a fault with the sensor that monitors the temperature of the water going to your radiators, meaning it cannot heat your home safely.

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

Centra heating supply sensor error (open or short)

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

30View →32View →

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