Central Heating Controls

VRC_470_CONTROL_ON_WALL_IN_KITCHEN A full range of heating controls will let you keep your home at a comfortable temperature without wasting fuel or heat, so you’ll reduce your carbon dioxide emissions and spend less on fuel bills.

If your home is heated by a traditional ‘wet’ central heating system of water-filled pipes and radiators running from a gas boiler. Then ideally a full set of controls should include a boiler thermostat, a timer or programmer, a room thermostat and thermostatic radiator valves (TRVs).

How much can you save with effective heating controls?

vailliant central heating gas boilers logoThe right set of controls will let you set your heating and hot water to come on and off when you need them and heat different parts of your home to different temperatures as required.

Here is a video of some specialised controls to go with the Valiant boilers we have been talking about:- Controls-2

According to the Energy Saving Trust the average savings you could make in a typical three-bedroom semi-detached home, heated by gas:

  • Install a room thermostat if you didn’t have one before: £70 a year
  • Fit a hot water tank thermostat: £30 a year
  • Upgrade to a factory insulated hot water cylinder: £40 a year
  • Turn down your room thermostat by one degree: £55 a year.

Heating controls can be upgraded without replacing your central heating system or boiler or if you are upgrading other parts of your heating system new controls can be added at the same-time. For example if you were replacing your boiler it would be sensible to service your system and bring it up to modern standards at the same time. So a power flush to clean out the radiators and pipework, add TRV’s to your radiators to get room by room temperature control and replace old thermostats and controllers with modern controls.

If you want to upgrade any aspect of your gas central heating call Steven Banks on 01462 636376

Types of Heating Controls

Room thermostats

EXOTEC_PLUS_AND_VRC_350These allow the heating to be on until the right temperature is reached then the heating is turned off until the temperature drops.


  • Your room thermostat should be set to the lowest comfortable temperature – normally in the range  18°C to 21°C. Experiment with turning your thermostat down a degree at a time to see  if you still feel comfortable.
  • You don’t need to turn your thermostat up when it is colder outside as the house will heat up to the set temperature whatever the outside temperature but it may take a little longer on colder winter days  so you might want to set your heating to come on earlier in the winter.

Programmable room thermostats

A programmable room thermostat allows you to set different temperatures for different times of the day.

Programmable thermostats are available that provide automatic time and temperature control of radiators.

Wireless controls make it easier to add controls throughout your central heating system with the minimum of fuss, mess and disruption.

Thermostatic radiator valves (TRVs)Honeywell TRV Thermostatic Radiator Valve

A thermostatic radiator valve controls the flow of water through a radiator allowing you to control the temperature of each room separately. Set them to the level you want for each room.

Cylinder thermostat

Honeywell cylinder thermostatIf your hot water is stored in a cylinder, the thermostat will prevent it being hotter than it needs to be by switching off the boiler when the right temperature is reached.


  • Turning the thermostat higher will not make the water heat up any faster, and the water heating will not come on if a time switch or programmer has switched it off.
  • Cylinder thermostats are usually fitted between one quarter and one third of the way up the cylinder. You should set them at between 60ºC and 65ºC. This is hot enough to kill off harmful bacteria in the water, but it’s also hot enough to scald. For extra safety consider installing a thermostatic mixing valve which will automatically ensure that hot water is at a safe temperature.

Boiler interlock

This is not a control but a system of wiring that turns the boiler off when neither the room thermostat nor the cylinder thermostat needs it. Without this the boiler can continue to ‘cycle’, wasting energy.

Boiler thermostat

Your boiler will have an inbuilt thermostat – usually a dial marked in numbers or from Min to Max. This sets the temperature of the water that will be pumped from the boiler through the radiators to heat your home.


  • Set your boiler control thermostat to a higher temperature than the cylinder thermostat. In most boilers, a single boiler thermostat controls the temperature of water sent to both the cylinder and radiators, although in some they are separate.
  • The higher this is set, the quicker and more effectively the system will heat your home. If this is not set high enough, when it is very cold outside your home may not reach your desired temperature.
  • If you have a room thermostat and a boiler interlock, you can set the boiler thermostat quite high, letting the room controls do their job. But set it lower if there is anyone vulnerable in the household who might hurt themselves by coming into contact with very hot radiators or pipes.

Timing controls

Programmer or time control

This will automatically switch your heating off and on at times you set. So off when you are out at work or when you are asleep.

They allow you to set ‘on’ and ‘off’ time periods separately for hot water and central heating, several times a day and more advanced models will allow you different time periods on weekends. There will be manual overrides to switch on or off as appropriate with the programmer resuming control next time it would have operated.VRC_470_CONTROL_ON_WORK_TOPTips:

  • Check that the timer on the programmer is correct before you set your programmes.
  • On some models you may need to adjust the time when the clocks change.
  • Work out how long your home takes to warm up and cool down – this will help you set the optimum time to switch on and off your heating. Choose a cold evening and time how long it takes for your house to warm up from cold to a comfortable temperature. Then turn the heating off completely and time how long it takes for the house to start to get uncomfortably cold. You can now set your timers including the warm up and cool down time.  If you insulate your home more, it will warm up more quickly and cool down more slowly, so you’ll save money on heating.
  • Set your water to heat up only when you need it. Keeping it constantly hot wastes energy. If your hot water cylinder is well  insulated, you may even find that the morning’s hot water stays hot enough to use in the evenings.

Service Timers for Landlords

Service Timers have additional features to help landlords comply with the requirements of Regulation 36 of the gas regulations 1998. The landlord, installer or service company can configure the Service Interval, the advance tenant notification period and how the controller will operate when the Service Interval has expired.

Programmer or time control with zones

You can get program controllers with heating control for separate zones of your home making the heating system more energy efficient and improving your comfort, as each zone will only be heated as required.

If you want to upgrade any aspect of your gas central heating call Steven Banks on 01462 636376