High
F.49 on Glow-worm Easicom3 System

Your boiler has lost the ability to communicate with its controls due to a wiring or electrical issue.

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 Easicom3 System installation & service manual, page 43.
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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