BoilerFaultCodesYour heat pump’s engine has stopped unexpectedly and is unable to restart, meaning your heating and hot water will likely stop working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Compressor Stall Error
What causes this fault?
This fault occurs when the main pump inside the unit attempts to start but becomes stuck or cannot maintain enough power to keep running. It is often caused by an electrical failure in the control board or a physical blockage that prevents the internal mechanism from spinning freely.
This issue is more frequent during extreme cold snaps when the system has to work much harder to start up against high pressure.
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 L52 — 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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