Medium
87 on Keston Heat 55

Your boiler is providing hot water to your taps as normal, but it is refusing to activate the central heating for 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 BUT DHW OK

From this model's manual
Verified against the Keston/Keston Heat 45 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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Related fault codes

81View →

All 36 fault codes on the Heat 55

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

1674757677787980818283848586888990BCC FaultCylinder Thermistor FaultError 20Ext’ Interlock OffFalse Flame LockoutFan FaultFlame LossFlow/Flue Thermistor FaultFlow/Return ReversedFlue Thermistor FaultIgnition LockoutLow Mains VoltageLow Water PressureOutside Sensor FaultOverheat LockoutPCB FaultReturn Thmr FaultToo Many Resets

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