BoilerFaultCodesThe 6 most common faults
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Locate the filling loop (usually a silver braided hose with one or two valves) underneath the boiler.Gradually open the valves to allow water into the system until the pressure gauge reads between 1.0 and 1.5 bar.Close the valves tightly and check the boiler display to see if the fault has cleared.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
Locate the external filling loop, which is a flexible metal or braided hose connecting two pipes beneath the boiler.Open the valves at both ends of the hose to allow mains water to enter the system while watching the pressure gauge.Stop filling once the needle on the pressure gauge reaches the green zone, typically between 1.0 and 1.5 bar, then tightly close both valves.
Your boiler has stopped working because it can no longer accurately measure the temperature of the water circulating inside it.
Full guide for F.00Your boiler has stopped working because it is unable to accurately measure the temperature of the water returning to it from your radiators.
Full guide for F.01Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside the system due to a faulty electrical connection or sensor.
Full guide for F.10Your boiler has detected an electrical fault with one of its internal temperature sensors, causing it to stop operating as a safety precaution.
Full guide for F.11on the Glow-worm Ultimate3 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 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
Avoid the next call-out bill
Monthly cover means no unexpected bills when your boiler breaks down.
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