BoilerFaultCodesYour heat pump has stopped working because the internal control computers are unable to talk to each other.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No connection Outdoor PCB to Inverter PCB
What causes this fault?
This fault occurs when the main computer board and the motor controller inside your outdoor unit lose their ability to send signals to one another. The most common reason is a loose or damaged wiring connection between these boards, though it can also be triggered by a localized electronic failure on one of the circuit boards themselves.
This fault can be more frequent during periods of heavy rain or high humidity, as moisture ingress into the outdoor casing can sometimes interfere with sensitive communication wiring.
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 H1 — 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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