BoilerFaultCodesThe 6 most common faults
01
E119 High DIY-safe
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
What to try first
Locate the filling loop (usually a silver braided hose with a valve) underneath the boiler.Open the valve(s) to allow mains water into the boiler.Monitor the pressure gauge on the front of the unit until it reaches between 1.0 and 1.5 bar, then securely close the valve.
02
E20 High Engineer
Your boiler has lost the ability to accurately measure the temperature of the central heating water, so it has shut down to prevent overheating.
Full guide for E2003
E110 High Engineer
Your boiler has detected that it is overheating and has automatically switched itself off to prevent damage.
Full guide for E11004
E125 High Engineer
Your boiler is struggling to pump water around your heating system correctly, which is preventing it from heating your home or water safely.
Full guide for E12505
E130 High Engineer
Your boiler has detected that the temperature of the exhaust gases leaving the flue is too high, causing it to shut down to prevent overheating.
Full guide for E13006
E133 High Engineer
Your boiler has stopped working because it cannot light its internal flame, which is likely due to an issue with the gas supply or the ignition process.
Full guide for E133on the Baxi Megaflo System
Pressure relief valvePressure sensorCentral Heating (CH) NTC SensorWiring HarnessPumpDiverter Valve
Based on parts cited in our fault code database. Your engineer will confirm what's actually needed after diagnosis.
Call a Gas Safe engineer if…
- You can smell gas or see signs of a leak
- The Baxi shows an Emergency or High severity code
- The boiler keeps locking out after repeated resets
- You've tried the DIY checks and the fault hasn't cleared
- There's visible water leaking from the boiler
- The flame is yellow or orange instead of blue