BoilerFaultCodesYour heat pump's internal electrical cooling system has become too hot and has shut down to prevent permanent damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Inverter High Temperature
What causes this fault?
This fault occurs when the electrical components that control the heat pump’s power supply reach an unsafe temperature. The most common reasons are a failure of the internal cooling fan or the thermal paste that transfers heat away from the electronics becoming less effective over time. Without proper cooling, the system is forced to stop to protect the expensive circuit boards from melting or burning out.
This fault is more common during the summer months or during sustained heatwaves, as the high ambient outdoor temperature makes it harder for the internal fan to keep the electronics cool.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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