BoilerFaultCodesThe 6 most common faults
Your boiler is not starting up because it cannot light the gas flame required to heat your water.
Check that your gas emergency control valve is in the open positionIf you have a prepayment meter, check that you have sufficient creditPress and hold the reset button for several seconds to restart the ignition sequence
Your boiler has become too hot and has switched itself off as a safety precaution to prevent damage.
Check that your radiator valves are open and not turned to 'off' or '0'.Ensure your system pressure is between 1 and 1.5 bar on the pressure gauge.Press and hold the 'R' (Reset) button for a few seconds to restart the boiler.
Your boiler has been manually reset too many times in a short period and has now locked itself for safety reasons.
Turn off the power supply to the boiler at the fused spur switchWait for approximately 30 to 60 secondsTurn the power back on to clear the lockout memoryIf the boiler locks out again, do not continue resetting and call a professional to find the underlying fault
Your boiler has detected that the water pressure in the central heating system is too low to operate safely.
Locate the filling loop (a flexible silver hose) underneath or near the boilerSlowly open the valves on the filling loop until you hear water flowingWatch the pressure gauge and close the valves once the needle reaches 1.5 bar
Your boiler has shut down because it detected that the exhaust gases are getting too hot, which is a safety measure to prevent internal damage.
Full guide for 03Your boiler has stopped working because it cannot communicate with the unit that controls the gas supply.
Full guide for 04on the Alpha E-Tec S
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 Alpha 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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