Medium
6 on Grant Vortex Eco External Wall Hung

Your boiler is repeatedly switching itself on and off instead of staying lit to heat your home.

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

Burner cycles on and off

From this model's manual
Verified against the Grant/Grant Vortex Eco External Wall Hung 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

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All 7 fault codes on the Vortex Eco External Wall Hung

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

1234521.0

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