Baxi Boiler E128 Error Code
Flame failure on Baxi boilers.
A flame failure lockout: the boiler couldn't establish or hold a flame. Baxi lists E128 among the codes a frozen condensate pipe can trigger, so a frosty morning is a strong clue. Otherwise the gas supply or the ignition is usually behind it.
Compatible models
Named as flame failure in the Combi 825 user manual and listed by Baxi among the frozen condensate codes; 128 also appears in the Baxi 124 and Duo-tec 2 Combi GA error tables.
Also shown as
The Combi 825 manual describes both E128 and E133 as flame failure. Check your own user guide for the wording on your model.
Difficulty
Start with the safe checks below; a worn part may need replacing.
Not sure you are reading the code right? See how to read Baxi boiler codes.
How to fix Baxi E128
Look for an outside cause first
Make sure the hob still lights and the prepayment meter isn't empty. In frost, switch the boiler off, find the condensate pipe outside and warm any frozen section with a heat pack or warm (not boiling) water.
Hold reset for 5 seconds
Press and hold the reset button for 5 seconds, as the Combi 825 manual describes. If the boiler fires and stays lit through a full heating cycle, keep an eye on it for a day or two.
When to call a technician
If the boiler won't reset, or E128 comes back with the gas and condensate pipe fine, the flame detection or ignition needs testing by a Gas Safe engineer.
Parts linked to E128
These are the parts an engineer usually checks for this code. They sit inside the sealed casing, so leave them to a Gas Safe registered engineer.
- Flame sensor (flame detection electrode)
- Ignition electrode and spark generator
- Gas valve and injector
- Condensate pipe and trap
Frequently asked questions
Which Baxi models show the E128 code?
Named as flame failure in the Combi 825 user manual and listed by Baxi among the frozen condensate codes; 128 also appears in the Baxi 124 and Duo-tec 2 Combi GA error tables.
Can I fix Baxi E128 myself?
Only the outside checks above. If they don't clear E128, the fix is inside the boiler and needs a Gas Safe registered engineer.
Other Baxi boiler codes
- E133Gas supply interrupted or flame failed to establish
- E118Low water pressure in the heating circuit
- E119Low primary water pressure (Platinum Combi)
- E110 / E130Overheat lockout (primary water or flue)
Last reviewed 2026-10-21. Codes and steps can vary by model; check your owner's manual.