High Lockout
J12 on Ideal HP290

Your heat pump's engine is drawing too much electrical power, causing the system to shut down to protect its internal circuits.

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

Inverter High Current

What causes this fault?

This fault occurs when the heat pump's internal power supply detects a sudden surge or excessive electrical demand from the system's moving parts. It is most commonly caused by an electrical failure within the compressor or the circuit board, where the component tries to draw more power than the system can safely handle. As a result, the unit shuts down immediately to prevent permanent damage to the sensitive electronics.

This fault is more common during the height of winter or peak summer, as the compressor has to work much harder to meet temperature demands, putting more strain on the electrical components.

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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