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Flame slow to stabilise during start up on Grant Vortex 15-20

Grant Vortex 15-20 fault code Flame slow to stabilise during start up

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

Insufficient air supply, incorrect nozzle, low fuel pressure, or insufficient draught

From this model's manual
Verified against the Grant/Grant Vortex 15 20 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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All 12 fault codes on the Vortex 15-20

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

26.036.0Boiler operating on overheat thermostatBoiler will not startBurner lock-outBurner pulsatesCombustion fumes smellFumes and puffing during startingOil odoursVisible smoke from flue or high smoke numberWater temperature low

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