Thermostatic Radiator Valves

Thermostatic radiator valves (TRVs)

A thermostatic radiator valve controls a single radiator by sensing the air temperature around it. As the room warms up, the valve gradually closes to reduce the flow of hot water; as it cools, the valve opens again. Each room holds its own temperature, so you are not paying to overheat rooms you don't use.

How to set a TRV

TRV heads are numbered, usually from a frost setting up to 5 or 6. Lower numbers suit bedrooms and hallways, and a middle setting suits most living rooms. Change the setting one step at a time and give the room a few hours to settle before adjusting again.

Where to fit them

TRVs can go on almost any radiator, but installers usually leave the radiator in the room with your main thermostat without one, so the two controls don't work against each other. Where possible, fit the head horizontally and keep it clear of curtains and furniture so it reads the room temperature accurately.

Choosing a TRV

Match the valve body to your pipework: angled for pipes from the floor into the side of the radiator, straight where the pipe lines up with the connection. Many TRVs are bi-directional, so they can go on either the flow or the return pipe; check the product page to be sure.

Prefer simple manual control? Browse all radiator valves.