High
23 on Ideal Maximiser SE 42

Your boiler has stopped working because its internal sensors or control system have detected a technical communication error.

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

Disconnect the connector of the sensor and press “reset”. When the same fault remains, short-circuiting in the cable loom has occurred or the control panel is defect, otherwise the sensor is defect.

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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All 40 fault codes on the Maximiser SE 42

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

- / A- / H- / Y= / H4 / A111213141516171819202122242526272829303132333435363738394041424344E / F

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