VURTU15 Straight Thermostatic Radiator Valve & Lockshield - Black

A Thermostatic Radiator Valve (or TRV) is a valve which is fitted to a radiator in a hot water heating system that is self-regulating (sets the temperature of the radiator automatically) based on the temperature of the room. It controls the room temperature by altering the flow of hot water to the radiator. In simple terms, it is a valve that can be set by the homeowner to turn on and off the radiator (when the heating system is active) based on the temperature of the room. This allows a level of temperature control in every room of the house, which one would not normally be able to achieve, even with a thermostat controlling the main heating system.