Furnace indicates gas valve or gas supply fault, no ignition despite fan and spark
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Critical safety: All gas-side diagnostics beyond visual checks must be performed by a certified gas technician.
- Basic user checks: Ensure the external gas isolation valve is fully open and that other gas appliances in the property operate normally.
- Visual inspection: With power off, inspect the Baxi gas valve and wiring harness for loose connectors or obvious damage. Do not attempt to open or adjust the valve.
- Professional tests: A technician will measure coil resistance, verify control voltage from the PCB during ignition, and check inlet and burner pressures with a manometer.
Do not attempt: Do not try to adjust the gas valve or bypass safety controls. If E09 persists, leave the appliance off and call a professional.
Repair Difficulty
Required Part
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