Boiler fault codes
Baxi Boiler Fault Codes Explained
Baxi codes start with E and a number. On older two-digit displays a three-digit code is split in two, so E133 flashes as E1 then 33. Read the whole code first, then use the pages below: some codes you can clear with a top-up or one reset, the rest need an engineer.
How to read a Baxi display
Older Baxi boilers with a two-character display, such as the Duo-tec, show two characters at a time. Two-digit codes appear as E then the number. Three-digit codes appear as E1 alternating with the last two digits, which is why so many people search for E1 on a Baxi when the real code is E119 or E133.
Other generations differ. The EcoBlue Advance uses E118 for low pressure and E117 for pressure above 3 bar, alongside symbols for "water pressure too low" and "resettable by user". The current 800 range shows a letter followed by numbers: E codes need a manual reset, while H and A codes usually clear once the condition behind them goes away. Check your user guide if the code on screen is not listed here.
Which Baxi codes can you clear yourself?
On the Duo-tec code table only E110 (overheat), E130 (flue overheat) and E133 (no flame or gas interruption) are resettable. Low pressure, E119 or E118 depending on the model, clears itself once you top the system up to 1 to 1.5 bar. Everything else on the list, including sensor faults, fan faults and circulation faults, points to a part that has failed.
- Reset once, by holding the selector or reset button for about five seconds.
- If the same code returns, stop resetting.
- In a frost, thaw the plastic condensate pipe outside with warm (not boiling) water first; a frozen pipe commonly locks a Baxi out on E133.
- Never remove the front casing. If you smell gas, open windows, shut off at the meter if safe, avoid switches, get out and call 0800 111 999.
When a Baxi code needs an engineer
Call someone when a resettable code keeps returning, when you top up pressure more than occasionally, or when the code names a component. Our Baxi boiler repair service starts with the £60 call-out at any hour, and the repair price is agreed with you on site before any work starts. Gas work is carried out by Gas Safe registered engineers. For pressure problems in more depth, see the Baxi boiler pressure guide and how to reset a Baxi boiler.
| Code | What it means | Can you clear it yourself? |
|---|---|---|
| E20 | Central heating temperature sensor fault | No, call an engineer |
| E28 | Flue sensor fault; in a frost, check for a frozen condensate pipe first | No, call an engineer |
| E50 | Hot water temperature sensor fault | No, call an engineer |
| E110 | Overheat: the safety thermostat has tripped | Yes, once; call if it returns |
| E117 | Water pressure too high, above 3 bar (EcoBlue, Duo-tec GA) | No, call an engineer |
| E118 | Water pressure too low (EcoBlue, Duo-tec GA, 800 Combi) | Yes, once; call if it returns |
| E119 | Water pressure below about 0.5 bar (Platinum, older Duo-tec) | Yes, once; call if it returns |
| E125 | Water is not circulating round the heating circuit | No, call an engineer |
| E130 | Flue overheat: the flue sensor has tripped | Yes, once; call if it returns |
| E133 | Gas supply interrupted or no flame detected | Yes, once; call if it returns |
| E160 | Fan or fan wiring fault | No, call an engineer |
| E168 | Control board lockout, sometimes after a power supply problem | Yes, once; call if it returns |
Baxi codes explained
- E1On most Baxi boilers with a two-digit display, E1 is not a fault on its own: it is the first half of a three-digit code, shown as E1 then two more digits. The digits that follow tell you the real fault.
- E119E119 means the water pressure in the heating circuit has fallen below the minimum the boiler will run on, about 0.5 bar. The boiler shuts down until the pressure is restored.
Questions people ask
What is the most common Baxi fault code?
Low pressure, shown as E119 on many models and E118 on some. It is usually cleared by topping up the system to 1 to 1.5 bar with the filling loop.
Why does my Baxi flash E1 and then another number?
The display can only show two characters, so three-digit codes are split. E1 then 19 is E119, E1 then 33 is E133.