common boiler fault codes
common boiler fault codes and their meanings for various popular boiler brands:
Worcester Bosch
- EA – Flame not detected
- E9 – Overheat
- A1 – Low water pressure
- A7 – Hot water temperature sensor fault
- C1 – Fan fault
Vaillant
- F22 – Low water pressure
- F27 – Flame detected when burner is off
- F28 – Ignition problem
- F29 – Flame extinguished during operation
- F75 – No pressure change when the pump is running
Baxi
- E119 – Low water pressure
- E133 – Gas supply fault
- E160 – Fan fault
- E168 – Error code not defined (often related to system issues)
- E110 – Boiler overheat
Ideal
- F1 – Low water pressure
- F2 – Flame loss
- F3 – Fan fault
- F4 – Thermistor fault
- L2 – Flame loss during operation
Glow-worm
- F1 – Ignition fault
- F4 – Ignition fault
- F9 – Overheat lockout
- F13 – Flow temperature sensor fault
- F16 – Flame detected when the burner is off
Ariston
- 108 – Lack of water in the system
- 501 – Burner lockout
- 302 – Heating sensor fault
- 104 – Overheating
- 301 – Domestic hot water sensor fault
These codes can vary slightly based on the model and series of the boiler. Always refer to the specific manual for your boiler model for the most accurate and detailed information.
