BoilerFaultCodesThe 6 most common faults
Your boiler has detected that the water pressure inside the system is too low for it to operate safely and efficiently.
Locate the external filling loop, which is a silver braided hose with one or two small valves connecting your cold mains pipe to your heating pipes.Open the valve(s) slowly to allow 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 restart the boiler to clear the error.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Locate the external filling loop, which is usually a flexible silver hose connected to the pipes underneath your boiler.Open the valves at both ends of the filling loop to allow cold mains water into the system.Watch the pressure gauge on the front of the boiler and close the valves once the needle reaches the green zone, typically between 1.0 and 1.5 bar.
Your boiler is currently unable to light the burner, which means it cannot produce any heat or hot water.
Check your gas meter to ensure the supply is on and you have credit if using a pre-payment meter.Ensure any other gas appliances in your home, such as a hob, are working to confirm gas is reaching the property.Press the 'Reset' button on the boiler control panel once to see if it successfully re-ignites.
Your boiler has detected an internal error that has caused it to stop working, and it needs to be restarted to attempt to clear the fault.
Locate the 'Reset' button on the boiler control panel.Press and hold the button for 2-3 seconds.Wait a few minutes to see if the boiler ignites and the fault code clears.
Your boiler has detected an issue with the sensor that reads the temperature of the water, which prevents it from heating up correctly.
Full guide for 28Your boiler has detected an issue with the water pressure or the flow sensor, which is preventing it from heating your home or water reliably.
Full guide for 40on the Main Eco Compact System
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 Main 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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