High
L52 on Ideal HP290

Your heat pump’s engine has stopped unexpectedly and is unable to restart, meaning your heating and hot water will likely stop working.

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.

What the manual says

Manufacturer manual

Compressor Stall Error

From this model's manual
Verified against the Ideal Hp290 installation & service manual, page 94.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the main pump inside the unit attempts to start but becomes stuck or cannot maintain enough power to keep running. It is often caused by an electrical failure in the control board or a physical blockage that prevents the internal mechanism from spinning freely.

This issue is more frequent during extreme cold snaps when the system has to work much harder to start up against high pressure.

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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