How Do Thermostatic Radiator Valves Work?

Thermostatic radiator valves are a great idea, saving you money and letting you control the temperature in every room individually. But how do thermostatic radiator valves work?

How Do Thermostatic Radiator Valves Work?

Depending how you set the valve, it will adjust the flow of water going into your radiator. As your room heats up, a capsule inside the valve head expands, moving a pin in the valve body so it closes. That will mean it receives less hot water from the boiler, so less goes into the radiator. As the room cools, the capsule contracts again, the pin pulls out of the valve body, and hot water can enter again.

 Thermostatic radiator valves have two main designs:

Liquid TRV design

A liquid TRV is more efficient, as liquid responds quicker to room temperature changes.

Wax TRV design

The wax capsule in older valves expands and contracts slower, and so these are cheaper.

Why is a thermostatic radiator valve a good idea?

Thermostatic radiator valves save energy. If you set them up TRVs correctly, you can control room temperatures individually and avoid overheating.

Do the numbers on the radiator valve refer to the actual temperature?

The numbers on the valve indicate the temperature of the room, not the radiator. A TRV detects the ambient temperature of specific room it’s in and then lets more or less hot water into its radiator to balance it.

My thermostatic radiator valve is stuck

A sticking valve is the most common issue with TRVs. Whether it’s stuck open or closed, it can be a real hassle. You usually find it gets jammed after a long time  when it has not been adjusted –after a long, cold winter or alternatively a long, hot summer. Avoid this by occasionally lubricating its piston with WD40 to prevent it from sticking.

L&W Heating and Plumbing

If you need to call on a Gas Safe registered plumber call L&W Heating and Plumbing experts on one of our regional numbers:-

Boiler Installation Wigan Specialist 01942 417220
Boiler Installation Runcorn Specialist 01925 394260
Boiler Installation St Helens Specialist 01744 776140
Boiler Installation Warrington Specialist 01925 394260
Boiler Installation Newton Le Willows Specialist 01925 394260
Boiler Installation Widnes Specialist 01925 394260