BoilerFaultCodesWhat the manual says
Manufacturer manualIgnition fault (lockout) Went out when lit
From this model's manual
Verified against the Vaillant/Vaillant Ecomax Pro 28e installation & service manual, page 26.
What causes this fault?
This fault occurs when the boiler successfully lights but then immediately loses the flame signal, causing it to shut down for safety. The most common reasons are worn-out sensors that can no longer 'see' the flame or a gas valve that isn't providing a steady enough flow of fuel to keep the burner lit.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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All 29 fault codes on the ecoMAX Pro 28E
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