BoilerFaultCodesThe 5 most common faults
Your boiler has stopped heating because the water pressure inside your radiator system has dropped too low to operate safely.
Locate the external filling loop, which is a flexible silver hose connected to two valves under the boiler.Gradually open both valves to let water into the system while watching the pressure gauge.Stop opening the valves 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 failed to light the flame safely, and it now needs a manual reset to try restarting.
Check your oil tank is not empty and the fuel supply valve is open.Wait for the red light on the burner to illuminate, then press and hold the reset button for 3 seconds.If the boiler tries to start but stops again, do not force repeated resets.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage.
Full guide for Red neonYour boiler has stopped working because it failed to start the heating process, triggering a safety system that keeps the burner turned off.
Full guide for Lock-outYour boiler has detected that it is getting too hot and has automatically shut down for safety reasons.
Full guide for Red neon lighton the Grant Vortex Combi 70
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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