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Central heating controls

Heat your home more efficiently and save on your energy bills ...

This page looks at various types of heating control. Your system won't have all of them.

Programmers/timers | Room thermostatsHot water cylinder thermostats | Thermostatic radiator valves


A timer or programmer allows you to control when your heating and hot water comes on and when it goes off.

This is handy because it means you can programme your central heating to fit around the way your home is used. If you’re not at home or are in bed asleep, then the heating doesn’t need to be on.

Most programmers are digital (they have a little screen). Older systems may have a non-digital timer that works by moving 'tappets' around a dial.

Here's a film about how to use a digital central heating programmer:

And here's a film about using a mechanical (non-digital) programmer:

The trick is to set your heating to come on half an hour before you get home or get up, and set it to switch off half an hour before you no longer need it. This is because an average home takes around 30 mins to heat up when the heating comes on and 30 mins to cool down when it goes off.

Say you get up at 7.30am, leave for work at 8.30am and get home at 6.00pm. It would make sense to set the heating to turn on at 7:00am, off at 8.00am and on again at 5.30pm. In the evenings you should set the heating to turn off half an hour before you go to bed.

Your programmer may also have the option of setting different on/off times at the weekend.

A well-insulated home warms up faster and cools down more slowly - meaning you can set the heating to come on later and turn off sooner, saving energy and money. Play with the timer to see what works best for your home.

Setting the hot water timing depends on the type of boiler you have. A combi boiler only heats up water when you turn on a hot tap, so you don’t need to programme it. But if you have a hot water tank, the water in the tank will need to be heated up every now and then during the course of the day.

The amount of times the water needs to be heated depends on how big and how well insulated your hot water tank is, and how much water your household uses. Try an hour in the morning and an hour in the evening - if you don’t run out of hot water, that’s enough!

What do the different settings on my central heating controls mean?

  • ‘Auto’ or 'Twice' means the heating will go on and off during the day at the times it has been programmed to do so.
  • ‘24hrs’ or ‘On’ means the heating stays on all the time.
  • Off’ means the heating will remain off all the time.
  • ‘All day’ or 'Once' means the heating will switch on at the first ‘on’ setting you have programmed and then remain on until the last ‘off’ setting of the day.
  • ‘Boost’ or ‘+1hr’ switches the heating on for a one hour ‘boost’ of heat.
  • ‘Advance’ moves the programmer to the next ‘on’ or ‘off’ setting in the daily cycle.

Room thermostat

Room thermostats are usually found in a hallway or sitting room. Their job is to monitor the temperature in the house and send a signal to the boiler telling it to switch off when the house is warm enough.

Thermostats are normally set between 18 and 21ºC. This is a comfortable temperature for most people. Some people need to keep their home warmer than 21ºC due to their age or health problems.

Some modern heating controls now combine the timer and the thermostat, allowing you to set different temperatures for different times of the day.

Here's our film about setting a programmable room thermostat:

Hot water cylinder thermostats

Hot water tank/cylinder thermostats regulate the temperature of your domestic hot water by switching off the heat supply from your boiler once the set temperature has been reached. They can save you money, and avoid wasting energy by over-heating your water.

If your hot water tank has its own thermostat, set it to around 60°C: hot enough to kill harmful bacteria like legionella, but not so hot that you’re wasting energy. If you find 60°C too hot, mixer taps can help.

Click here to read more about hot water cylinders (including thermostats and cylinder insulation).

Thermostatic radiator valves

Thermostatic Radiator Valves allow you to control the temperature of a room by regulating the flow of water through the radiator.

If, for example, during the day you spend most of the time downstairs, you could set the TRVs on the downstairs radiators to medium or high, and leave the upstairs radiators on low.

It’s not generally a good idea to turn radiators off completely for weeks or more, because very cold rooms can develop damp and mould. Instead, set the radiators in rooms you’re not using to low, and close the doors so that the heat from your warm rooms doesn’t travel there.

Smart Heating Controls

With smartphones and tablets, it is now possible to control your heating system with a software application or ‘app’. These new apps allow you to turn your heating and hot water on and off or adjust the temperature from wherever you are, as long as you can connect to the internet.

There are advantages to being able to control your heating while you’re out. For example, your heating may be scheduled to come on at 5.30pm. But if you were unexpectedly delayed in getting home, you could use the app on your phone to tell the heating to come on later, saving you money on heating the house unnecessarily.

Some apps go further and will use the GPS technology in your smartphone to automatically increase the heating as you get closer to your home or decrease it as you leave home. Family members or housemates can be added to your account and the app will monitor who is coming home first or who is last to leave. Some apps will control the heating depending on the current weather forecast – for example, the app will reduce the temperature setting if the forecast is for unseasonably warm weather.

There are a number of products that offer smart heating controls – the table below gives a few examples.

HiveiOS & AndroidNo£199
TadoiOS & AndroidYes£249 one-off cost or £6.99 per month
ClimoteiOS & Android plus SMS for non-smartphonesNo£299
Nest ThermostatiOS & AndroidNo, but thermostat learns the household's habits£249

This information is available to download as an easy read leaflet.

Download the PDF

Download this PDF document

This information is available as a freely downloadable PDF from this page.

For more domestic energy advice, view all our advice pages.

Your gas heating and hot water: How it works

For boilers with a mechanical (non-digital) timer.

Your gas heating and hot water: How it works

For boilers with a digital timer.

Priority Services Register

If you live in the green or blue areas, we can sign you up to your local priority services register if you're over 60 or you rely on electricity for medical or mobility reasons or you have a hearing or visual impairment or a long-term health condition.

Click here for details.

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