Baxi boiler error codes
9 codes that Baxi publishes for its boilers, each with what it means, the likely cause, what you can safely check and when to call a Gas Safe registered engineer. Tap your code:
Gas boiler: do only the checks its user manual gives you — read the pressure gauge, top up through the filling loop, press the reset button, thaw a frozen condensate pipe at ground level. Keep the casing on and leave sealed parts alone. Anything else is for a Gas Safe registered engineer. If you smell gas, call the National Gas Emergency Service on 0800 111 999. Codes that need one are marked Gas Safe engineer.
Read this first
Baxi boilers show an E and a number. On the Platinum+ 40 Combi, whose 2019 user guide this page follows, a three-digit code is shown in two halves: E133 appears as “E1” alternating with “33”, while a two-digit one like E50 appears as “E” then “50”. The guide sorts the nine codes in its table into three kinds: faulty components (E20, E28, E50, E125, E160) that need your installer or service engineer; overheating (E110, E130) and gas or ignition (E133), where you may reset once by holding the selector on reset for five seconds; and low water pressure (E119), which goes away after repressurising.
E119 Water pressure too low
- What it means
- The water pressure switch has not operated: the primary (heating) water pressure is below 0.5 bar.
- Likely cause
- Water lost from the heating system. Baxi says a pressure that needs regular topping up points to a fault or a leak.
- What you can safely check
Gas boiler: do only the checks its user manual gives you — read the pressure gauge, top up through the filling loop, press the reset button, thaw a frozen condensate pipe at ground level. Keep the casing on and leave sealed parts alone.
- Read the pressure gauge. With the system cold and the boiler off it should be at least 0.5 bar; running, normally 1.0 to 2.0 and never above 2.5.
- Repressurise the system with the “Easy-Fill” filling link under the right-hand side of the boiler, the way your installer showed you. The boiler should then work.
- When to call a Gas Safe registered engineer
- Contact your installer or a Gas Safe registered engineer if you have to repressurise regularly, or if the gauge reads 3 bar or more (Baxi calls that a fault and says to contact your installer or service engineer as soon as possible).
Source: Baxi, Platinum+ 40 Combi user guide (2019): 5.3 fault indication, table of error codes Checked 2026-09-28.
E133 Gas supply interrupted or flame failure
- What it means
- The gas supply was interrupted, ignition failed, or the flame was not detected. The display shows “E1” then “33”.
- Likely cause
- No gas reaching the boiler, or a failed ignition.
- What you can safely check
Gas boiler: do only the checks its user manual gives you — read the pressure gauge, top up through the filling loop, press the reset button, thaw a frozen condensate pipe at ground level. Keep the casing on and leave sealed parts alone.
- Make sure the gas supply has not been turned off.
- Turn the selector switch to the reset position and hold it there for at least 5 seconds.
- When to call a Gas Safe registered engineer
- If the boiler does not relight, or E133 comes back regularly, contact your installer or a Gas Safe registered service engineer.
Source: Baxi, Platinum+ 40 Combi user guide (2019): 5.3 fault indication, table of error codes Checked 2026-09-28.
E110 Safety thermostat operated
- What it means
- The primary water overheated and the safety thermostat operated.
- Likely cause
- Overheating of the water in the boiler.
- What you can safely check
Gas boiler: do only the checks its user manual gives you — read the pressure gauge, top up through the filling loop, press the reset button, thaw a frozen condensate pipe at ground level. Keep the casing on and leave sealed parts alone.
- Turn the selector switch to reset and hold it there for at least 5 seconds.
- When to call a Gas Safe registered engineer
- If the boiler does not relight, or E110 comes back regularly, contact your installer or a Gas Safe registered service engineer.
Source: Baxi, Platinum+ 40 Combi user guide (2019): 5.3 fault indication, table of error codes Checked 2026-09-28.
E130 Flue sensor operated
- What it means
- The flue temperature sensor (NTC) operated: the flue system overheated.
- Likely cause
- Overheating in the flue system.
- What you can safely check
Gas boiler: do only the checks its user manual gives you — read the pressure gauge, top up through the filling loop, press the reset button, thaw a frozen condensate pipe at ground level. Keep the casing on and leave sealed parts alone.
- Turn the selector switch to reset and hold it there for at least 5 seconds.
- When to call a Gas Safe registered engineer
- If the boiler does not relight, or E130 comes back regularly, contact your installer or a Gas Safe registered service engineer.
Source: Baxi, Platinum+ 40 Combi user guide (2019): 5.3 fault indication, table of error codes Checked 2026-09-28.
E20 Heating sensor fault
- What it means
- Central heating temperature sensor (NTC) fault.
- Likely cause
- A faulty component.
- What you can safely check
Nothing for the owner to check: this one is for a Gas Safe registered engineer.
- When to call a Gas Safe registered engineer
- Gas Safe engineer Make a note of the code and contact your installer or a Gas Safe registered service engineer: Baxi lists it as a faulty component.
Source: Baxi, Platinum+ 40 Combi user guide (2019): 5.3 fault indication, table of error codes Checked 2026-09-28.
E28 Flue, air pressure or condensate fault
- What it means
- A flue sensor fault, an air pressure switch fault, a blocked flue, a blocked condensate drain or a wiring fault.
- Likely cause
- Baxi lists it with the faulty-component codes, and notes it may also mean a blocked flue or condensate drain.
- What you can safely check
Nothing for the owner to check: this one is for a Gas Safe registered engineer.
- When to call a Gas Safe registered engineer
- Gas Safe engineer Make a note of the code and contact your installer or a Gas Safe registered service engineer: Baxi lists it as a faulty component.
Source: Baxi, Platinum+ 40 Combi user guide (2019): 5.3 fault indication, table of error codes Checked 2026-09-28.
E50 Hot water sensor fault
- What it means
- Hot water temperature sensor (NTC) fault. Shown as “E” then “50”.
- Likely cause
- A faulty component.
- What you can safely check
Nothing for the owner to check: this one is for a Gas Safe registered engineer.
- When to call a Gas Safe registered engineer
- Gas Safe engineer Make a note of the code and contact your installer or a Gas Safe registered service engineer: Baxi lists it as a faulty component.
Source: Baxi, Platinum+ 40 Combi user guide (2019): 5.3 fault indication, table of error codes Checked 2026-09-28.
E125 Circulation fault
- What it means
- The water is not circulating properly in the primary (heating) circuit.
- Likely cause
- A faulty component.
- What you can safely check
Nothing for the owner to check: this one is for a Gas Safe registered engineer.
- When to call a Gas Safe registered engineer
- Gas Safe engineer Make a note of the code and contact your installer or a Gas Safe registered service engineer: Baxi lists it as a faulty component.
Source: Baxi, Platinum+ 40 Combi user guide (2019): 5.3 fault indication, table of error codes Checked 2026-09-28.
E160 Fan fault
- What it means
- A fault in the fan or its wiring.
- Likely cause
- A faulty component.
- What you can safely check
Nothing for the owner to check: this one is for a Gas Safe registered engineer.
- When to call a Gas Safe registered engineer
- Gas Safe engineer Make a note of the code and contact your installer or a Gas Safe registered service engineer: Baxi lists it as a faulty component.
Source: Baxi, Platinum+ 40 Combi user guide (2019): 5.3 fault indication, table of error codes Checked 2026-09-28.
A code that is not listed here
Other Baxi models use other codes. For a code not on this list, Baxi’s user guide tells you to contact your installer or service engineer; Baxi’s literature library has the guide for each model.
We list only codes the source below states. If your code is not here, it may belong to a model the source does not cover: your model’s manual is the authority.
Related pages
Source
Every code on this page comes from this page, published by Baxi and read on the date shown. Meanings are written in our own words; nothing is taken from other makes, other models or third-party code sites.
- Baxi: Platinum+ 40 Combi user guide (2019): 5.3 fault indication, table of error codes Checked 2026-09-28.