BoilerFaultCodesThe 6 most common faults
Your boiler has temporarily stopped working because the water pressure inside the system has dropped too low.
Locate the filling loop under your boiler or near the pipes.Open the valves slowly to let mains water into the system until the pressure gauge reads between 1 and 1.5 bar.Close both valves tightly and reset the boiler.
Your boiler has detected that the water pressure inside the system has dropped too low to operate safely.
Locate the external filling loop, which is usually a small silver braided hose with one or two valves located underneath the boiler.Open the valve(s) slowly to allow mains water into the system until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.Close the valve(s) tightly and check that the error code clears.
Your boiler has lost track of how hot the water inside the heating system is because a temperature sensor has failed.
Full guide for E20Your boiler is struggling to clear exhaust gases safely and has turned itself off to prevent a potential hazard.
Full guide for E28Your boiler is struggling to detect the temperature of the water it is trying to heat, so it has shut down to prevent overheating.
Full guide for E50Your boiler has detected that water is not flowing properly around your heating system, so it has safely shut down to prevent overheating.
Full guide for E125on the Baxi Platinum+ 40 Combi
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
Avoid the next call-out bill
Monthly cover means no unexpected bills when your boiler breaks down.
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