Medium
0 4 on Grant Vortex Blue

Your boiler is warning you that the water in your area is extremely hard, which causes significant scale build-up inside the internal components and will eventually prevent the unit from heating water efficiently.

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

Very hard <370 mg/l calcium carbonate

From this model's manual
Verified against the Grant/Grant Vortex Blue installation & service manual, page 18.
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

0 1View →0 2View →

All 25 fault codes on the Vortex Blue

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

1 32 23 14 021.026.036.0BURNER panel LED flashing fast (2/sec)Burner reset light green/red alternate flash (0.5s)Burner reset light green/red fast flash (0.2s)Burner reset light orange steadyBurner reset light orange/green alternate flash (0.5s)Burner reset light orange/green fast flash (0.2s)Burner reset light red fast flash (0.2s)Burner reset light red flash (0.5s on, 2.5s off)Burner reset light red flash (0.5s)Burner reset light red steadyBurner reset light red/green inverted flash (2.5s on, 0.5s off)Burner reset light red/orange inverted flash (2.5s on, 0.5s off)CH PUMP panel LED flashing fast (2/sec)DHW PUMP panel LED flashing fast (2/sec)DHW PUMP panel LED flashing slow (1 per 2s)FLOW panel LED not lit with hot tap openOVERHEAT panel LED lit

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