BoilerFaultCodesThe 6 most common faults
Your boiler has detected a problem with how it disposes of waste gases or condensation, causing it to shut down for safety.
Check the white plastic condensate pipe outside for signs of freezing or blockagesThaw a frozen external pipe using a hot water bottle or warm (not boiling) waterRestart the boiler by turning the selector switch to the reset position for five seconds
Your boiler has switched itself off because it has reached an unsafe temperature, usually due to a lack of water flow or a blockage.
Check that the boiler pressure is between 1 and 1.5 bar on the gaugeEnsure all radiator valves and the isolation valves under the boiler are fully openAllow the boiler to cool down for 30 minutes and press the 'Reset' button
Your boiler water pressure has dropped too low for the system to operate safely, which is usually caused by a natural loss of pressure over time or after bleeding radiators.
Locate the filling loop (usually a silver flexible hose) underneath or near the boiler.Slowly open the one or two taps/valves on the filling loop until you hear water flowing.Watch the pressure gauge and close the valves tightly once the needle reaches between 1.0 and 1.5 bar.Check if the E119 code has cleared or press the 'Reset' button.
Your boiler is struggling to move water around the system, which is causing it to overheat and shut down for safety.
Check that the boiler pressure is between 1.0 and 1.5 barEnsure all radiator valves and isolation valves under the boiler are fully openGently bleed air from your radiators using a radiator key
Your boiler has failed to light or maintain a flame, which means your heating and hot water will not work until the gas supply or ignition is restored.
Check that your gas meter has credit and the isolation valve is openCheck if other gas appliances, like your hob, are working correctlyPress and hold the 'R' reset button for 5 seconds to attempt a restart
Your boiler has sensed that water is not moving correctly around the internal system before it attempts to ignite.
Check that your central heating valves (at the boiler) are fully openEnsure all radiator valves (TRVs) are turned to their highest settingAttempt to reset the boiler by turning the selector switch to 'R' for five seconds
on the Potterton Gold System ErP
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 Potterton 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