Medium
H. on Halstead Eden Vbx

Your boiler has accidentally entered a testing mode used by engineers, meaning it is currently running at a very low power setting and may not heat your home or water effectively.

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

SERVICE mode (flashing H.) - appliance runs at minimum CH output

Shared across the Eden VBX 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.
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

H.View →

All 3 fault codes on the Eden Vbx

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

8.2 Diagnostic LED Indicators8.3 Faulting Finding Codes

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