In Summary

1. Find the sweet spot (usually 3) and leave it at this setting to allow it to automatically regulate the room temperature (place a green dot on the sweet spot).
2. If you believe your TRV is broken let the facilities or maintenance team know.
3. Please do turn down the radiator thermostat before opening a window and return it to the green dot when you close the window.
4. Keep radiators clear to allow heat to circulate.
5. Be aware: your radiator will cool down when the room has reached its set temperature. This is normal, there is no need to adjust anything.
6. Be aware: turning a TRV up to MAX will not heat the room up faster. You may become uncomfortably hot and reduce the heat flow to other areas.
7. Be aware: Turning a TRV OFF(and not putting it back) will result in you being cold the next morning.

View the Teatime Talk – Spot the Dot: Your heating Sweet Spot for more information. 

Radiator thermostats shut off the flow of heat to the radiator when the room gets warm enough. There is a temperature sensor that closes a valve to reduce the flow of hot water in the radiator. When the room cools down, the valve opens and allows heat to flow again. In this way it maintains the room at the level you have set it to.

The numbers or scales on your thermostatic radiator valves do not correspond to a precise temperature but rather to a level of comfort. Through trial and error, you will find the setting that meets your needs.

It’s not possible to precisely convert the scales of your thermostatic radiator valve to degrees Celsius. However, an approximate conversion can be made. For example, valve position * corresponds to a frost protection temperature and position 3 to approximately 20°C.

You can use this table as a guide to help you determine which setting might work best for you.

How do I properly set my thermostatic radiator valves?

We recommend you set them to 3 to start with in office areas but lower in corridors (where people are just walking through (1-2). The contrast allows you to register the warmer temperatures in offices and provides a greater feeling of comfort.  

When set at 3 the office room should stay at a comfortable 20°C. Any higher and you may get uncomfortably hot. This is a waste of energy. When set lower, the space may be too cool or cold, especially if you are sitting still at a desk.

NOTE: The radiator can feel cool to the touch, even when the heating is on, if the room has reached the set temperature. This is normal, you do not need to adjust anything. Am I warm enough? If yes, then leave well enough alone.

You may need to play around a little at the beginning until you find the sweet spot for you. If the room is not warm enough – turn it up a little (one or half a setting) and down a little if the room gets too hot. Allow one hour for the temperature to stabilise.  Once you find this sweet spot you could place a green dot at the ideal setting (your Energy Team can provide the dots).

You do not need to turn the radiator thermostat up if it is colder outside and be aware that turning it up higher or to MAX will not heat your area faster – it will just stay on for longer and the room will thus get hotter – potentially uncomfortably hot. How quickly a room heats up has more to do with the boiler and radiator size than the radiator setting. Overheating some areas of the building could mean there is a reduced heat flow to other areas.

NOTE: Turning the TRV up higher or to MAX will not heat your area faster

If you feel the room is too warm you can check to see if the radiator has gone off as it will cool from the bottom first. You can turn the TRV down (or off) but please remember to put it back to the sweet spot before the end of the day. If you forget to return the TRV to the sweet spot there will be no heat in the radiator the next morning.  

NOTE: Resist the temptation to turn the TRV up and down. Find your Sweet Spot and leave it there. 

Solar gain – rooms on the south side of the building can sometimes get a lot of sunshine. This will add to the heat from the radiators until the thermostat senses the room has reached its set temperature and then turns off. Solar energy will continue to heat the room and it may overheat. (computers and people also produce heat.) Pulling blinds can help to reduce solar gain.

It is entirely natural when it is hot to want to open the windows (fresh air is all good too) – just keep in mind that if the room cools a bit the radiator will start to come on again and you could be cooling the room as fast as the radiator is heating it. In this case do turn down the radiator before opening a window – but please remember to turn it back to the sweet spot when you close the window.

Remember if radiators are blocked by furniture or curtains then the heat cannot circulate around the room and the room can be cooler or can take longer to warm up. Space is limited in offices, but as best you can, try to keep the radiators clear.