Your heat pump has stopped working because its internal computer board is having trouble communicating with or powering the compressor.
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 main control system loses the ability to properly manage the compressor, which is the 'heart' of the machine. The most common reason is an electrical failure within the inverter circuit board or a breakdown in the wiring that provides power and instructions to the compressor.
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 LC6 — 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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