High
L45 on Ideal HP290

Your boiler has identified that the internal fan is incompatible or incorrectly configured, causing the system to shut down for safety.

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

Wrong Fan Fitted

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 boiler's control chip fails to recognize the specific fan installed in the unit. The most common reason is a communication error between the fan and the main circuit board, often caused by the wrong part being installed during a repair or a software mismatch on the board itself.

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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