BoilerFaultCodesThe 6 most common faults
Your boiler's heating element has safely shut itself down as a precaution, usually due to a temporary interruption in the ignition process.
Ensure your oil supply valve is fully open and there is fuel in your tank.Wait at least 60 seconds for the system to reset.Locate the red reset button on the burner unit and press it firmly once.
Your boiler has stopped working as a safety precaution and needs a manual reset to try and restart the burner.
Check that your oil tank has sufficient fuel and the isolation valve is open.Locate the red reset button on the burner control box.Press the button firmly once to attempt a restart; if it fails again immediately, do not keep pressing it.
Your boiler has stopped working because the water level inside your heating system has dropped too low to operate safely.
Locate the external filling loop, which is a flexible braided hose connected to your pipework.Open the valves at both ends of the hose to let water into the system until the pressure gauge reads between 1.0 and 1.5 bar.Close both valves tightly and remove or disconnect the hose if required by your specific model setup.
Your boiler has lost all power and is effectively switched off.
Check your home's main fuse box to see if a trip switch has flippedCheck the fused spur switch located near the boiler to ensure it is turned onEnsure the plug connecting the electrical supply to the boiler is firmly pushed in
Your boiler has stopped working because the water pressure inside your heating system has dropped too low to operate safely.
Locate the external filling loop (a flexible metal hose) connected between your mains water supply and the boiler pipework.Open the small valves on both ends of the hose to allow water into the system until the pressure gauge reads between 1.0 and 1.5 bar.Firmly close both valves and ensure no water is dripping from the hose connections.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent any damage or safety hazards.
Full guide for Overheat thermostaton the Grant Vortex Eco External Wall Hung
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 Grant 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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