Medium
4.15 on Ideal Logic Max Heat

Your boiler is providing central heating for your radiators as normal, but is failing to heat your hot water tank or taps.

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 HW But CH Ok

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 or external controls fail to signal that the hot water needs heating, even though the central heating for your radiators is working fine. The most common reason is a faulty motor or sensor that prevents the heat from being diverted away from the radiators and toward your hot water cylinder.

Engineer required

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

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