BoilerFaultCodesYour heat pump has stopped working because the internal computer that controls the motor has detected an electrical problem.
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 control board detects an electrical irregularity or a communication failure with the motor that drives the heating process. It is typically caused by a component failure within the electronics or a physical fault in the compressor itself that prevents it from starting safely. In some cases, a loose connection or a sudden power surge can trigger this safety shutdown.
This fault can sometimes appear during summer or winter extremes when the compressor is required to work harder to maintain high temperature demands.
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 J65 — 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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