Radiator Valve

By Author: Mohan Chen
Total Articles: 434
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A Thermostatic Radiator Valve (TRV) is a self-regulating valve fitted to hot water heating system radiators. The TRV controls the temperature of a room by regulating the flow of hot water to the radiator. Thermostatic Radiator Valves (air vent valves) also exist for steam radiators.

Many years ago the first ideas for heating controls saw the light of day, but it was not until 1943 when Mads Clausen, founder of Danfoss, invented the first radiator thermostat that the development of TRVs became serious. However, from the first invention to mass production to the European market it took almost 15 years, and it was not until 1973 when the first oil crisis hit the world that the installation of TRVs really took speed.

Today TRVs have a wide market distribution and acceptance worldwide as an energy efficient and competitive technology. In spite of this there is still a huge potential for further implementation of TRVs as replacement of old manual valves to benefit the environment and reduce the energy costs for people around the world.

A TRV consists of two ...
... parts: a valve that opens or closes to control the hot water flow and a sensor that controls the opening of the valve. The sensor contains an actuator with a sensing substance, which adjusts the valve opening based on the temperature in the room and via a physical connection between the actuator-spindle and the valve-spindle/cone.

The sensors are for the most part made of plastic in many different designs and shapes. The actuator usually contains a sensing substance, such as wax, liquid or gas.

The valves are mainly made by brass or bronze and have different sizes, shapes and connections to the radiator. The majority of Manual Radiator Valves are mounted on the piping connected to the radiator; however, the valves may also be mounted as an integrated part of the radiator.

TRVs are self-regulating devices, which control the temperature in the room based on an individually set temperature and heat load. TRVs can work together with outdoor temperature controls, supply flow temperature controls, pressure controls and time set-back devices.

The self-regulating principle is shown in this animation. The overall principle can be described in this way:

1.The actuating device in the sensor is a steel container containing a sensing substance, either wax, liquid or gas. All three substances expand or contract depending on the temperature in the room.

2.A spindle system in the sensor transfers the axial movement from the actuator to the valve by interaction between the sensor spindle and the valve spindle. In the valve a rubber cone fixed on the valve spindle interacts with the valve seat and thereby regulates and controls the flow of hot water through the valve to the radiator inlet.

The process is completely self-contained and without complex electronic controls. The TRV keeps the room temperature at a desired level even through fairly wide swings in indoor temperature due to external conditions such as sudden temperature drops, solar radiation, wind velocity or wind direction.

After installing TRVs, owners have to get used to the self-regulating principle which means that they do not have to turn the thermostat up and down. When room temperatures vary, the valve automatically opens or closes to regulate the flow of hot water until the desired temperature is achieved. Only if the desired room temperature has to be changed or if windows are opened or closed for ventilation does the sensor setting need to be adjusted.

A TRV should not be fitted on a radiator where it is in the same room as the main house/rooms thermostat, as this can lead to innacurate overall house temperature control. Refer to BS5449 or equivalent.

TRVs are suitable for all kind of radiator systems, radiators, convectors and towel dryers. Designs of the sensors can be tailored to suit the specific applications. TRVs are cheap and easy solutions with a significant potential for energy savings and CO2 reductions from heating installations. In fact the replacement of a manual heating control with a TRV can save at least 100 kg CO2 per year.[citation needed]

When dimensioning a heating system in a building, it is necessary to perform a precise calculation of the total system. As part of this calculation it is important to secure proper hydraulic balancing of the complete heating system. For this balancing, the presetting feature in the valve or a special hydraulic balancing valve can be used.

The new Buckingham valve range have been manufactured to allow three valve configurations, straight, straight angled, and right angle return, making them fully customisable and suitable for nearly all plumbing layouts. The valves can be ordered to fit a wide variety of pipework, including steam, and can be perfectly incorporated within bespoke radiator installations.

Manufactured with a painstaking attention to detail and to strict quality control guidelines, the new Buckingham valve range is exquisitely crafted. The traditional valves are machined, giving them the style, quality and design edge over alternative and inferior cast products. The meticulous precision with which the valves are manufactured is instantly recognisable in the incredibly smooth action which results from the exactness of the fittings.

There are also a greater number of finishes to choose from than is often found in alternative valve ranges. The available finishes are Polished Brass, Antique Brass, Bright Nickel, Satin Nickel, Chrome and Antique Copper. Such a plethora of options enables the right finish to be found which complements the existing pipework within the original plumbing layout.

The final design feature separating the new Buckingham valves from the pack are the magnificent five spoke hand-wheel manual valves. Beautifully finished, the hand-wheels are crafted from solid walnut, effectively combining eye catching design with practical functionality.