No hot water? Here are some things you can check

It’s never a nice surprise to find that your hot water’s not working. But before you call an expert, there are a few things you can check yourself. Let’s look at how you can get your hot water running again without an engineer visit.

If you have no hot water, the first thing to check is whether your boiler’s stopped working. Different boilers can show faults in different ways – the display could change colour or show an error code. In that case, you might need a professional boiler repair.

If your boiler’s working but there’s still no hot water in the house, you should check:

●      The boiler is set to ‘on’ for hot water

●      The programmer is set to ‘heating and water’ rather than ‘heating only’

●      The timer’s working and showing the right time

You can also try resetting your boiler – there might be a ‘reset’ button for this. After pressing the button, wait a few minutes and then switch the boiler back on.

On older boilers, the pilot light is a small blue flame that’s always alight. If it’s not on, the boiler can’t work. Modern boilers – installed since 2005 – don’t have a pilot light.

If the pilot light has gone out, you should follow the manufacturer's instructions to relight it. But a pilot light that keeps going out needs to be checked by a Gas Safe engineer.

Don’t try to relight it if you smell gas – instead, call the National Gas Emergency Service on 0800 111 999.

The most common reason for not having hot water is that your boiler has stopped working. But if you’ve checked that already, here are a few more things you can try.

First, check if your other gas appliances are working. If they are, a tripped switch might have cut the power to the boiler. Go to your fuse box and turn the switch for the boiler circuit back on. If your boiler keeps tripping a fuse, you’ll need a Gas Safe engineer to come and find out why.

But if your other gas appliances aren’t working, look at your gas meter. If the meter says ‘ON’ (but you have no gas) call the National Gas Emergency Service on 0800 111 999.

If your gas meter says ‘OFF’, you might need to add credit. Next, try pressing a button to wake the meter up. Then, if there’s a shut-off valve, check it’s in the ‘on’ position. Finally, you should contact your energy supplier for help.

To check older gas meters (not smart meters), first turn off all your gas appliances, including pilot lights. After 30 minutes, see if the numbers on the meter have stopped moving. If they haven’t, call the National Gas Emergency Service on 0800 111 999.

Some older meters also have a valve on the gas pipe going to the meter. If the handle is at 90 degrees to the pipe, it’s off. Turn it parallel to the pipe to let the gas flow again.

Sometimes boiler settings and thermostat controls can get changed by accident. A child might have played with the buttons, or a dial could have been knocked as someone went past. The settings can also change after a power cut or when the clocks go forward or back.

If the temperature is set too low (under 21 degrees Celsius, for example) your boiler might not come on at all. Try setting it a bit higher. If the thermostat panel doesn’t show anything, you might need to change the batteries. You can find out more in our guide to boiler temperature settings.

If your hot water stops working when it’s cold outside, you could have a frozen pipe. Signs of this are:

●      No water from the hot taps, or only a trickle

●      You can see a pipe is frozen

●      Odd smells from the taps or drains

Never try to thaw a frozen pipe with boiling water, an electric heater or a blowtorch. They’re too hot and dangerous to use for this.

Instead, you can use a hot water bottle and a hairdryer. Find out more in our guide to fixing frozen water pipes. You can also watch our video:

If your boiler’s working but there’s no hot water, check your radiators. Are they not getting hot, or do they have cold spots?

If so, the radiators might have a build-up of sludge that’s stopping the water from flowing freely. A heating engineer can fix this with a chemical clean called a ‘powerflush’.

Trapped air in your heating system is another possible cause. You might be able to fix this by draining your radiators. To learn how, see our radiator troubleshooting guide.