Start with the basics
If you have a prepaid meter, ensure there’s enough credit. This is a common cause of why a boiler would stop working. Another basic check you can do is to check your gas appliances such as your cooker are working properly. It’s a good to idea to also check plugged-in electrical devices are working, to eliminate if the fuse box has been tripped.
Had a power cut recently?
Sometimes power cuts can reset your boiler timer. Getting it working again can be as simple as reprogramming the times. Look through the instruction manual for your boiler model for information on how to do reprogram it.
Check outside pipes
With freezing weather conditions, sometimes water condensate pipes that are located outside of your property can freeze up. If this is the case, the boiler will not turn on until the ice is thawed.
Adjust your thermostat
It sounds simple, but having your thermostat set lower than 21 degrees may stop your heating from coming on. Turn it up higher and see if that helps get your boiler started.
Check the boiler pressure gauge
Boiler pressures can drop regularly, especially if there is an underlying problem with the system. If the boiler pressure is one bar or less, the boiler may be unable to start. Topping up the pressure yourself is a pretty straightforward job. Follow your boiler manual to find out the exact process required.
Reset the boiler or check that the pilot light is on
If you have a boiler that was made before 2004, it most likely has a pilot light. If it’s off, read your boilers manual to see how to turn the light on. If you have a more modern boiler, check the process to reset it.