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Boilers: Boiler and heating controls 

The best central heating controls

Buying an efficient new boiler is only the first step in saving money on your heating costs.

Outdated heating controls waste your money

Upgrading from an old-fashioned thermostat to a programmable room thermostat gives you more options for controlling your heating

Out-of-date central heating system components and controls can lead to wasting energy and potential problems in several areas.

Hot water cylinder supplied by gravity-fed water - stored water is slow to reheat.

No cylinder thermostat - excessive stored water temperature and risk of scalding.

No cylinder insulation - heat is wasted through the surface of the cylinder.

No room thermostat - rooms are too hot.

Lack of thermostatic radiator valves (TRVs) - excessive room temperatures and poor heating system balancing.

Absence of boiler interlock - the boiler stays hot and cycles unnecessarily during programmed heating periods.

As a householder, you might not notice these issues, but they'll be wasting your money in the long run.

Also, take a look at our page on boiler energy efficiency to find out more about how much an inefficient one could be costing you, and to work out if you need a new one.

Get the best heating controls

The type of heating controls you need will depend on the type of heating system you have and whether your hot water comes direct from your boiler or via a hot water cylinder.

You should discuss which controls you need for your home with your heating engineer when you have a new boiler or heating component installed.

Talk to your boiler installer about the type of controls you need and how to set them

There are four main types of heating control:

timer – turns your boiler on or off at set times

room thermostat – measures how warm your room is and adjusts the boiler operation accordingly

programmer – lets you set different times and temperatures for different days of the week

thermostatic radiator valves (TVRs) – allow you to adjust the temperature of individual radiators and turn them off completely

To find out more about how each type controls your heating see our guide to boiler and heating controls.

Controls to use with heat-only boilers

Your system should include:

programmable room thermostat

separate timing capability for hot water

hot water cylinder thermostat

thermostatic radiator valves on all rooms except the one with the room thermostat

motorised valves - to control the flow of water from the boiler to heating and hot water circuits

automatic bypass valve - used to maintain a minimum water flow rate through the boiler when TVRs are operating

boiler interlock - a wiring arrangement to prevent the boiler firing when there is no demand for heat

Find out more about heat-only boilers.

Controls to use with combi boilers

Your system should include:

 programmable room thermostat

thermostatic radiator valves on all rooms except the one with the room thermostat

automatic bypass valve - used to maintain a minimum water flow rate through the boiler when TVRs are operating

boiler interlock - a wiring arrangement to prevent the boiler firing when there is no demand for heat

Using heating controls effectively

Effective heating controls let you take charge of when, where and at which temperature your heating is operating.

Simple changes that will make efficient use of your heating controls can make a big difference:

Turning down your thermostat by just 1°C can save you £55, according to the Energy Saving Trust.

Zone your heating to the rooms you use the most.

Programme your heating to only work when the house is occupied.

Set your thermostatic radiator valves (TVRs) to a low temperature.