BoilerFaultCodesYour boiler has lost its connection to the gas supply due to an internal electronic communication failure, meaning it cannot ignite to provide heat or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Interruption of gas supply (internal error)
What causes this fault?
This fault occurs when the boiler's main control board loses the ability to communicate with the gas valve, preventing the system from releasing fuel for ignition. The most common reason is a malfunctioning printed circuit board (PCB) or a loose connection in the internal wiring harness. In some cases, the gas valve itself may have developed an electrical fault that keeps it from responding to the boiler's commands.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like E135 — 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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