Grant Vortex Eco External Wall Hung Fault codes & diagnostics

6 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

System Oil 2008-2015
Download the Grant Vortex Eco External Wall Hung manual The official installation & service manual (PDF) — the exact document these fault codes were verified against. PDF

The fault code is already on your display

Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Severity at a glance

Each cell = one fault code. Hover to identify.
6 Unrated
Just want the most common Grant Vortex Eco External Wall Hung faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes

All 6 documented codes

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Status & diagnostic codes

1 operating states & engineer diagnostics

Not faults — these are normal operating states. Tap to expand.

21.0 Diagnostic Your boiler is currently running at its maximum designed heat output, which is a status message rather than a breakdown of the appliance.
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