Medium
NO DHW BUT CH ON on Johnson Starley Quantec C

Your boiler is working fine for your radiators, but a specific internal component is failing to switch over to provide hot water to your 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 domestic hot water but central heating operates correctly

From this model's manual
Verified against the Johnson Starley Quantec C 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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