What to do if your central heating stops working

Switching on the boiler to find that you’ve no central heating or hot water is far from ideal. Especially if it happens in the middle of winter. But before you call a Gas Safe engineer, take a look at these 12 simple fixes that might just get you up and running again without the need for a call-out.

electrical sockets

Check your other gas appliances and electrical sockets

You might be in the midst of a power cut, in which case nothing will be working. So if your gas hob and power sockets seem OK, move on to the next check.

Check your isolator and trip switches

The electricity supply to your boiler might have been interrupted. So if any of the switches in your fuse box are 'off', switch them on again and give your heating another try.

isolator and trip switches
prepay customer

If you’re a prepay customer, check that you’re not out of credit

We know this sounds obvious, but it does happen!

Check your boiler pressure

Make sure the pressure gauge on your boiler control panel reads roughly 1 to 1.5 bar. If it doesn’t, carefully use your water valve to adjust the pressure as needed. We have a handy guide to fixing boiler pressure issues here.

Bear in mind that you may have to reset your boiler once you’ve re-pressurised the system. So if you’re in any doubt about how to do so check your user manual.

boiler pressure
thermostat temperature setting

Make sure your thermostat is set high enough

We recommend having your heating set to around 21℃. So if yours is lower, increase the temperature on the thermostat to see if that triggers the boiler. If this doesn’t work, try putting your heating on full for a little while.

Check that your timer settings are correct

If you’ve had a recent power outage – or even if you’ve brushed against the control panel – your timer settings might have been accidentally changed. Double check this and adjust them if you need to. Then set the heating to come on in 15 minutes’ time, to make sure it’s registering properly.

timer settings
temperature controller

Make sure your temperature controller is turned up

Your boiler will have two dials on the control panel. One for water temperature and one for your central heating. Make sure the heating temperature dial is turned all the way up and try your heating again.

Check your loft tank if your system is open vented

If you’ve got a small plastic or steel tank in your loft it means your boiler system is likely to be open vented, and you may need to check if the float ball valve has got stuck. Only attempt this if it’s safe for you to get to it. You'll find the float ball inside the small plastic or steel tank and you’ll see little or no water in there. Very gently, move the float ball valve arm to free it but don't use force. Once you’ve done this your water should start to circulate again.

open vented boiler system
frozen pipes

Make sure your pipes haven’t frozen

If it’s especially chilly outside and your pipes have frozen, you can try thawing them yourself using hot (but not boiling!) water. Or you can apply a hot water bottle or other form of warm compress to the affected pipe. Now give your heating another go.

Check that your pilot light hasn’t blown out

If your boiler has a permanent pilot light, you’ll need to check your manufacturer's instructions on how to relight it. And if you can’t get it to light again, have an engineer take a look. Any persistent pilot light issues should always be checked by a Gas Safe professional.

boiler pilot light
boiler reset

Try resetting your boiler

Your boiler’s reset button should be located somewhere on the front panel. Check your boiler manual for instructions on how to reset your specific system and see if this gets things going again.

Switch the boiler off and on again

You should find the power switch close to the boiler or in an airing cupboard. Switch it off for a few seconds and then turn it back on again to see if this kickstarts your heating.

boiler switching on and off

And if you’ve tried everything and you still have no heating or hot water:

Have a Gas Safe engineer come and take a look at it for you. Our British Gas engineers are here to support and you can book an appointment here.

If it’s cold outside take measures to keep warm indoors. Close any doors and windows and if you have draught excluders, use them. Pop some warm clothing on and consider using an alternative heat source, such as an electric heater, if you have one. Just remember to use heating appliances safely and keep them at least a metre away from anything combustible.

To keep your central heating running smoothly all year round, have it serviced annually by a Gas Safe engineer. If you have our HomeCare plan, you’ll already be covered for a boiler service each contract year. If you’d like to know more about a one-off service, you can get a quick and easy quote here.