How much does it cost to fix Johnson Starley error code E31?

Typical repair cost for the Johnson Starley E31 fault is £90-250 including labour.

E31 High

Johnson Starley E31 Fault Code

Q: What does the Johnson Starley E31 fault code mean?

Your boiler has lost its connection to the thermostat or external controller, meaning the two devices can no longer talk to each other to manage your heating.

The Johnson Starley E31 fault code means: your boiler has lost its connection to the thermostat or external controller, meaning the two devices can no longer talk to each other to manage your heating.. It appears on 2 Johnson Starley models in our database.

Technical description: Remote control communication error

Typical repair cost £90-250 (including labour)

DIY fix possible

Check if the batteries in your wall thermostat need replacing.Ensure the thermostat is within signal range of the boiler.Turn the boiler power off and on again at the fused spur to restart the communication sequence.

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Johnson Starley models that show the E31 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Johnson Starley E31 fault code information on this page is sourced and cross-checked against the official Johnson Starley service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026