BoilerFaultCodesYour boiler has lost its ability to communicate with its external controls, such as your thermostat, due to an electrical glitch in the internal data wiring.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: eBUS voltage fault
What causes this fault?
This fault occurs when there is an electrical conflict or a short circuit on the communication wires that link your boiler to your thermostat. The most common reason is a hardware failure in the external control receiver or a wiring fault that is preventing the internal computer from sending and receiving data correctly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like F.49 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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