Emergency
2 / C on Ideal Maximiser SE

Your boiler has detected that it is getting dangerously hot and has shut itself down to prevent damage or fire risk.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Safety sensor of the heat exchanger is overheated.

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 emergency 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 111 fault codes on the Maximiser SE

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

-. / A-. / H-. / Y-. H=. / H=. H0 / A0 / H0 / Y0A0H0L0U0Y001011 / C1C2 / F2 / P2 / U2C2F2P2U030044 / A4 / C4 / F4 / L4 / P4 / U4 / Y4A4C4F4L4P4U4Y005055 / A5 / Y5A5Y6 / A6 / C6 / H6 / L6A6C6H6L7 / A7A7C7F7H7L0088L9A9C9F9H9L9P9U0101001112131415016160171718018192021232425262728290293031323435363738394041041424360EF

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