BoilerFaultCodesWhat the manual says
Manufacturer manualTank NTC sensor not detected.
Shared across the Greenstar Zwbr 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 connection between your boiler and your hot water cylinder is broken or interrupted. The most common reason is that the temperature probe attached to your water tank has failed, or the electrical wiring connecting that probe back to the boiler has become loose or damaged.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Related fault codes
All 25 fault codes on the Greenstar 30HE
Seeing a different code? Every code this model can display, in one place.