High
396 on Grant Vortex Eco

Your boiler is struggling because the ventilation system providing fresh air to the unit is insufficient or blocked, preventing safe and efficient operation.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Vent B (cm²)

From this model's manual
Verified against the Grant/Grant Vortex Eco installation & service manual, page 30.
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 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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Related fault codes

397View →398View →

All 53 fault codes on the Vortex Eco

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

10121821.02226.0313636.04454616992116143198232286348429594727728729A1.2A1.3A2.2A3.2Blinking REDBurner lock-outConstant REDDHW PUMP indicator FLASHINGFast flashFlashes redFlashes red/greenGREENGREEN blinkingLED offLock-outLockoutLOW PRESSUREOFFORANGEORANGE blinkingOverheatOverheat thermostatREDRED blinkingRED fast blinkingRED steady ONSlow flash

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