Medium
4.12 on Ideal Logic Max Heat

Your boiler is providing central heating as normal, but it is currently unable to heat your hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

No DHW Operation

From this model's manual
Verified against the Ideal Logic Max Heat 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.

What causes this fault?

This fault occurs when the boiler's internal components stop responding to a request for hot water, even though the central heating continues to work. The most common reason is a failure in the communication between the flow turbine, which detects when you turn a tap on, and the diverter valve that directs heat to your water.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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