High
E31 on Ravenheat TS 90

Your boiler is having trouble communicating with your external smart thermostat or heating controls, meaning it cannot receive the correct signals to turn on or off.

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

OpenTherm communication error

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

E02View →

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