High
F.49 on Glow-worm Energy Regular

Your boiler's communication wires are experiencing a electrical short or power clash, meaning the boiler and your thermostat can no longer 'talk' to each other.

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.

What the manual says

Manufacturer manual

eBUS fault: Voltage too low. Short circuit on eBUS, eBUS overload or two power supplies with different polarities on the eBUS

From this model's manual
Verified against the Glow Worm Energy Regular installation & service manual, page 30.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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