Verified boiler fault code
Main Heating E133 Fault Code (Eco Elite System)
Interruption of gas supply or flame failure.
Safety disclaimer
Fault code summary
- Manufacturer
- Main Heating
- Fault code
- E133
- Fault type
- Gas supply, Ignition, Flame failure
- Severity
- lockout
- Reset
- The manual says turning the selector to Reset for a minimum of 5 seconds can relight the boiler when E133 is displayed; repeated faults require investigation.
- Applicable models
- Main Eco Elite 24 System ErP, Main Eco Elite 28 System ErP
Quick answer
Interruption of gas supply or flame failure.
What does this fault code mean?
Interruption of gas supply or flame failure.
Common causes
- Gas supply interrupted.
- Ignition failed.
- Flame not detected.
Symptoms
- The facia displays E133 and the burner does not remain lit.
What can the homeowner safely check?
- Check only that the boiler has power and whether other household gas appliances are affected.
Boiler reset information
The manual says turning the selector to Reset for a minimum of 5 seconds can relight the boiler when E133 is displayed; repeated faults require investigation.
When should I call an engineer?
Contact a suitably qualified heating engineer when the fault persists, the boiler locks out, or the manufacturer instructions do not resolve it. For gas appliance work in the UK, use a Gas Safe registered engineer.
Engineer diagnosis
- Investigate gas supply, ignition, flame detection and associated wiring.
Applicable boiler models
Related fault codes
- E110 — Eco Elite System
Safety thermostat operated.
Read fault code - E119 — Eco Elite System
Water-pressure switch not operated; the manual states this is shown below 0.5 bar primary-water pressure.
Read fault code - E125 — Eco Elite System
Circulation fault in the primary circuit.
Read fault code - E131 — Eco Elite System
Interruption of power supply while in fault mode.
Read fault code - E160 — Eco Elite System
Fan or fan-wiring fault.
Read fault code - E20 — Eco Elite System
Central-heating NTC fault.
Read fault code - E28 — Eco Elite System
Incorrect PCB fitted.
Read fault code - E50 — Eco Elite System
Hot-water NTC fault.
Read fault code
Manufacturer documentation
Main Eco Elite System Installation & Service ManualE133 indicates that the gas supply has been interrupted, ignition has failed or the flame has not been detected.
Last verified
2026-09-12
Frequently asked questions
What does Main Heating E133 mean?
Interruption of gas supply or flame failure.
Can I reset a Main Heating E133 fault?
The manual says turning the selector to Reset for a minimum of 5 seconds can relight the boiler when E133 is displayed; repeated faults require investigation.