E50
Potterton
Gas Valve / Combustion Control Fault
Boiler shows E50, fan runs but no ignition, may indicate gas valve or combustion fault
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
Faulty gas valve, Incorrect gas valve adjustment, Blocked injector or burner, PCB gas valve drive fault
How to Fix / Troubleshooting
Safety first: Isolate gas and power. Only Gas Safe registered engineers may work on gas valves and combustion settings.
User checks:
- Confirm other gas appliances work to rule out supply interruption.
Engineer checks:
- Measure voltage at gas valve during ignition; if present but no gas flow, suspect valve failure.
- Check burner and injector for blockage; clean as per manufacturer instructions.
- Verify inlet gas pressure and burner pressure with a manometer; adjust valve if required.
- If valve and burner are OK, test PCB gas valve output and replace PCB if faulty.
After any gas valve work, a full combustion analysis must be carried out.
Advertisements
Repair Difficulty
Professional Required
5/5
Advertisements