High Lockout
Hd on Ideal HP290

Your main heat pump unit is unable to talk to the secondary unit, meaning the system cannot coordinate properly to heat your home.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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 Master Heat Pump to Slave Heat Pump

What causes this fault?

This fault occurs when the electrical link between the two main heating units is broken, preventing them from sharing data. The most common reasons are a loose or damaged communication cable, or a failure in the electronic control boards that manage the system's signals.

This fault can sometimes occur after periods of heavy rain or storms if moisture enters the external wiring enclosures and interferes with the communication signal.

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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Related fault codes

H1View →H2View →H3View →

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