Boiler displays E133, no ignition, often after gas supply interruption
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
Safety first: If you smell gas, do not attempt to reset the boiler. Ventilate the area, do not use electrical switches, and contact the gas emergency number.
User checks:
- Check that the gas meter emergency control valve is open.
- Confirm other gas appliances (hob, fire) are working.
- Press the reset button once and wait for the boiler to complete its ignition sequence.
Engineer checks:
- Bleed air from the gas line if recently worked on, following Gas Safe procedures.
- Check gas valve operation and burner pressure.
- Inspect and clean the burner and injector.
If E133 persists with a confirmed gas supply, a Gas Safe engineer must investigate ignition and gas valve components.