BoilerFaultCodesThe 6 most common faults
Your boiler has tried to light several times but has been unable to create a flame, meaning you will not have any heating or hot water.
Check if other gas appliances in your home, such as a gas hob, are working correctly to ensure gas is reaching the property.Verify that your gas pre-payment meter (if applicable) has sufficient credit.Try resetting the boiler by following the instructions in your user manual to clear the fault.
Your boiler has shut down because it has detected it is getting too hot, which is a safety feature to prevent damage.
Check that all radiator valves are fully open to allow water to flow.Ensure there are no blockages in the system by checking if any external pumps are running.Try resetting the boiler via the control panel once it has cooled down.
Your boiler has stopped working because the water pressure in the central heating system has dropped too low.
Locate the metal braided filling loop underneath or near your boiler.Slowly open the one or two valves on the loop until you hear water flowing.Watch the pressure gauge until it reaches between 1.0 and 1.5 bar, then close the valves tightly.
Your boiler has detected that the water pressure in the central heating system is too low or too high for it to operate safely.
Check the pressure gauge on the front of the boiler or under the casing; it should be between 1.0 and 1.5 bar.If it is below 1.0, use the external filling loop valves to top up the system until the needle reaches the green zone.If the pressure is too high, bleed a radiator to release water and lower the pressure.
Your boiler has failed to light after several attempts and has locked itself for safety, leaving you without heating.
Check that your gas pre-payment meter (if applicable) has credit.Ensure other gas appliances in your home, such as a hob, are working correctly.Press and hold the reset button for five seconds to attempt a restart.
Your boiler has switched itself off because it became too hot, acting as a safety measure to protect the internal components.
Wait at least 15 minutes for the unit to cool down completely.Check that all internal registers and warm air vents are open and not blocked by furniture.Press the 'Reset' button on the control panel to see if the heater restarts.
on the Johnson Starley J32 System ET
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 Johnson Starley 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