BoilerFaultCodesYour heat pump has stopped working because a sensor detected that the internal system is getting too hot, likely due to a lack of proper airflow or low refrigerant levels.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Compressor Discharge Temperature High Error
What causes this fault?
This fault occurs when the temperature of the gas leaving the compressor becomes dangerously high, causing the system to shut down to prevent internal damage. It is usually caused by the system struggling to move heat away efficiently, often due to a leak in the refrigerant gas or a mechanical part failing to regulate the flow correctly.
This issue is more frequent during summer heatwaves, as the high outdoor temperature makes it much harder for the unit to keep its internal components cool while operating.
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 9.1.28 — 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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