High
-. / Y on Ideal Maximiser SE

Your boiler is stuck on the heating setting and cannot control its temperature properly, leading to overheating or a lack of hot water.

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

Unit is constantly fired for the central heating and does not modulate in reverse direction. The central heating installation is overheated or not sufficiency heated; the hot water tank is not heated. Unit is constantly operative for the central heating, at the capacity adjusted with the hot water potentiometer.

From this model's manual
Verified against the 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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