BoilerFaultCodesThe 6 most common faults
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Locate the external filling loop, which is usually a flexible metal or silver braided hose underneath the boiler.Open the two valves at either end of the loop slowly to allow water to enter the system.Watch the pressure gauge on the front of the boiler until the needle reaches the green zone, ideally around 1.5 bar.Close both valves tightly and ensure the filling loop is disconnected if required.
Your boiler has stopped working because 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 your boiler.Gradually open the valve(s) 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 valves tightly to stop the flow of water and check if the error code clears.
Your boiler has stopped because the water pressure inside the heating system has dropped too low.
Locate the filling loop (a silver flexi-hose) underneath the boilerOpen the small valve or tap attached to the loop until you hear water enteringWatch the pressure gauge on the front of the boiler until the needle reaches 1.5 barClose the valve tightly and check for any visible leaks
Your boiler has detected that there is not enough water flowing through the system, meaning it has switched itself off to prevent overheating.
Check your system pressure gauge; if it is below 1 bar, locate the filling loop under the boiler.Open the filling loop to allow water into the system until the gauge reads between 1 and 1.5 bar.Close the filling loop tightly and reset the boiler using the reset button or dial.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Locate the filling loop, which is a silver braided hose with one or two small valves under the boiler.Gradually open the valves to let water into the system until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.Close the valves tightly and check the display to see if the error code clears.
Your boiler has detected that the water pressure inside your heating system is too low to operate safely.
Locate the filling loop (usually a silver braided hose with one or two valves underneath the boiler).Slowly open the valve(s) to allow water to enter the system while watching the pressure gauge on the front of the boiler.Stop filling once the needle reaches the green zone, typically between 1.0 and 1.5 bar, then ensure the valves are fully closed.
on the Main Insul 7
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