BoilerFaultCodesWhat the manual says
Manufacturer manualSafety switch-off: Overheating temperature reached - Incorrect earth connection between cable harness and product, flow or return NTC defective (loose connection), black discharge via ignition cable, ignition plug or ignition electrode
From this model's manual
Verified against the Vaillant/Vaillant Home Regular Installation And Maintenance installation & service manual.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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All 33 fault codes on the Home Regular 12
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