BoilerFaultCodesYour heat pump’s main engine is struggling to pull enough power to start up correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Compressor Start Error
What causes this fault?
This fault occurs when the heat pump's compressor tries to turn on but cannot reach its required operating speed. It is usually caused by an electrical component failing to provide the initial 'push' needed to start the motor, or a blockage preventing the internal parts from moving freely.
This issue is more frequent during the first cold snap of autumn, as components that have sat idle during the summer may struggle to restart under increased demand.
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 L5E — 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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