Low
11 on Ideal Maximiser SE 42

A diagnostic switch inside your boiler's control panel has been accidentally left turned on, and simply needs to be switched back off.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

The test switch on the control panel is switched on; put it back in off position.

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.

DIY fix possible

Locate the control panel on your boiler.Find the internal test switch.Flick the switch back to the 'off' position.

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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 / A121314151617181920212223242526272829303132333435363738394041424344E / F

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