BoilerFaultCodesWhat the manual says
Manufacturer manualReturn NTC fault
Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
What causes this fault?
This fault occurs when the boiler's control board loses communication with the sensor that monitors the temperature of the water coming back from your radiators. The most common reason is that the internal sensor has suffered an electrical failure or the wiring connecting it to the main board has become loose or damaged.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Related fault codes
All 52 fault codes on the Flexicom hx
Seeing a different code? Every code this model can display, in one place.