High
35 on Ideal Maximiser SE 42

Your boiler's internal control module is failing to communicate with the fan, causing the system to shut down immediately after trying to start.

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

BIM is defective or not properly connected, when started, the fan will rotate for a moment and then stops.

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

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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Avoid the next call-out bill

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Related fault codes

All 40 fault codes on the Maximiser SE 42

Seeing a different code? Every code this model can display, in one place.

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