By Lewis Wiggins, Gas Safe registered engineer · Updated
If your boiler stops working, check the power supply, that the gas is on, the pressure gauge (usually 1 to 1.5 bar when cold), your thermostat and timer settings, and whether the condensate pipe has frozen in cold weather. If it still will not work, call a Gas Safe engineer. If you smell gas, leave the property and call 0800 111 999.
1. Check the power
Make sure the boiler is switched on at the fused spur and that there has not been a power cut or tripped switch.
2. Check the gas supply
Check other gas appliances are working and that the gas is on at the meter. If you have a prepayment meter, check it has credit.
3. Check the pressure
Most sealed systems should read around 1 to 1.5 bar when cold. If it is lower, your boiler manual will explain how to repressurise using the filling loop. If the pressure keeps dropping, there may be a leak and you should call an engineer.
4. Check the thermostat and timer
Make sure the thermostat is set higher than the room temperature and the timer is calling for heating. Check batteries in wireless thermostats.
5. Check for a frozen condensate pipe
In freezing weather, the plastic pipe that runs outside from your boiler can freeze and cause a lockout. Pouring warm (not boiling) water along it can thaw it. Then reset the boiler.
6. Try a reset
Many boilers have a reset button. Only reset once or twice. If the fault returns, call an engineer.
If you smell gas
Do not use switches or flames, open windows, turn off the gas at the meter if safe, leave the property and call the National Gas Emergency number on 0800 111 999.
Still stuck? Request a boiler repair or call Lewis on 07867 388453.