E09
Sime
Gas Valve Control / Modulation Fault
Boiler shows E09, burner stops unexpectedly, may relate to gas valve control
Advertisements
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.
Advertisements
Possible Causes
Defective gas valve coil, Loose gas valve connector, Faulty modulation control from PCB, Incorrect gas valve adjustment
How to Fix / Troubleshooting
Safety first: Turn off gas and power. Only Gas Safe–registered engineers should work on gas valves and combustion settings.
- Reset boiler: Attempt a reset. If E09 recurs quickly, do not continue to operate the boiler.
- Visual inspection (engineer task): Remove the case and inspect the gas valve wiring harness and plug. Ensure it is fully seated and not heat-damaged.
- Check coil resistance (engineer task): Measure the gas valve coil resistance and compare with Sime specifications. Replace the valve if out of range or intermittent.
- Verify modulation signal (engineer task): Using a multimeter, check that the PCB is providing the correct modulation voltage/current to the valve during operation.
- Commissioning check: After replacing a gas valve, the engineer must set burner pressure and combustion values (CO/CO₂) according to Sime instructions using a flue gas analyser.
Advertisements
Repair Difficulty
Professional Required
5/5
Advertisements