High Lockout
H1 on Ideal HP290

Your heat pump has stopped working because the internal control computers are unable to talk to each other.

Call an engineer soon

Book a Gas Safe engineer within 24 to 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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