BoilerFaultCodesYour heat pump has stopped working because the internal safety system has detected a communication error or a power supply issue.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fault code displayed on Heat Pump Controller/Control Box interface (technical description not provided in the snippet).
What causes this fault?
This fault occurs when the main control system loses its connection with the internal components, essentially meaning the different parts of the heat pump are no longer 'talking' to each other. The most common reason is a loose or damaged communication cable, or a failure in the circuit board that processes these signals. Without this constant flow of data, the system shuts down as a safety precaution.
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 E01 — 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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