BoilerFaultCodesThe 6 most common faults
01
S.54 High DIY-safe
Your boiler has paused because the water pressure is too low or the water is not circulating properly around your heating system.
What to try first
Check the pressure gauge on the front of the boiler; it should be between 1 and 1.5 bar.If the pressure is below 1 bar, use the filling loop underneath the boiler to top up the system with water.Ensure all your radiator valves are fully open to allow water to circulate freely.
02
S.32 High Engineer
Your boiler is pausing because its internal air-flow fan is not spinning at the exact speed required to operate safely.
Full guide for S.3203
F.00 High Engineer
Your boiler is unable to measure the temperature of the water inside it, so it has safely shut down to prevent overheating.
Full guide for F.0004
F.01 High Engineer
Your boiler is struggling to accurately measure the temperature of the water returning to it, so it has stopped working to prevent potential overheating.
Full guide for F.0105
F.10 High Engineer
Your boiler has stopped working because it is unable to accurately measure the temperature of the water flowing through the system due to a faulty electrical connection or sensor.
Full guide for F.1006
F.11 High Engineer
Your boiler has stopped working because it is unable to accurately read the temperature of the water returning to it, causing it to shut down for safety.
Full guide for F.11on the Glow-worm EASICOM 3 25r
Central heating pumpPressure sensorFilling loopFan assemblyPrinted Circuit Board (PCB)Wiring harness
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 Glow-worm 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
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