Medium
93 on Keston 30C

Your boiler is providing hot water for your taps but is failing to heat your radiators.

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 CH OPERATION BUT DHW WORKS OK

From this model's manual
Verified against the Keston/Keston 30c 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.

DIY fix possible

Check that your room thermostat or smart hub is turned up and calling for heatEnsure the central heating timer or programmer is set to 'On'Replace batteries in your wireless room thermostat if applicable

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Related fault codes

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All 31 fault codes on the 30C

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

8182838485868788899091929495BCC FaultFalse Flame LockoutFan FaultFlame LossFlow Temperature Overheat LockoutFlow Thermistor FaultIgnition LockoutLow mains voltageLow water pressureNo water flow lockoutOutside sensor faultOverheat lockoutPCB FaultReset the boilerReturn Thermistor FaultToo many resets

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