High
E31 on Ravenheat 100

Your boiler is having trouble communicating with your external thermostat or heating controls, preventing it from knowing when to turn on.

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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