Your heat pump has stopped working because of an internal electrical communication issue within its power control system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Inverter Error
What causes this fault?
This fault occurs when the heat pump's internal computer loses the ability to communicate with the system that manages the power sent to the compressor. The most common reason is a failure of the inverter circuit board or a loose connection in the internal wiring, which prevents the unit from regulating its energy output.
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 LC3 — 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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