One of the main applications of a thermostatic expansion valve is temperature control in a residential building or building. For the correct use of this device, it must be installed on a heating radiator in the room in which it is important to maintain the desired temperature.
Device selection
When choosing this device, it is important to consider such three parameters as:
- type of device;
- technical parameters of the valve;
- product cost and manufacturer.
If we talk in more detail about each of these selection criteria, then you should always start by determining the type of device. On this basis, products can also be divided into several groups:
- The first group includes those types of devices that differ in the way they are mounted on the pipe. Among these types, the following can be distinguished: a direct thermostatic valve, which is installed on pipes running parallel to the ground. The angle valve is designed for installation on those pipes that are brought out of the floor, axial products are installed on pipes coming out of the wall.
- The second group includes devices that differ in such a feature as the type of heating system. Thermostatic valves for a single-pipe system are characterized by greater throughput than valves for a two-pipe system.
Thermocouple
It is important to say that the valves are divided into several groups not only according to the types of systems with which they work. Different groups of these products differ in such a thing as a thermocouple, as well as a working fluid. If we talk about filling, the devices can run on gas, liquid or paraffin. Gas types of elements are considered the most high-class, the liquid occupies a middle niche, and the thermoelements working with paraffin became the worst in their characteristics.
There are also slight differences in the way the thermocouple is adjusted. There are two categories of element adjustment. The first category includes those devices that are tuned to the general average parameters by production specialists. This is called element presetting. The thermostatic valve with open adjustment is the second category, the feature of which is that each user can independently configure the thermocouple.
Performance data
After the type of device was determined in the selection process, you can proceed to its selection according to technical parameters. Thermostatic valve must provide the following parameters:
- The maximum operating temperature should be up to 200 degrees Celsius.
- The pressure that this device must withstand is from 16 to 40 bar.
- It is important that the valve is completely made of materials that are not susceptible to mechanical or corrosive effects. The best in these qualities are parts made of bronze, brass or steel.
- The diameter of the heating pipe in the house and the diameter of the control valve must necessarily match.
- The last most important characteristic for a valve is the ability to mount it on the desired system. For example, if the controller is mounted by means of a thread, the parameters on the valve and pipe must match.
Manufacturers and cost
It is logical that the cost of the product is formed not only from those characteristics that were listed above. This parameter also fluctuates depending on which manufacturer produced a particular valve. Currently, there are several companies whose products are considered the best on the market:
- The first representative is the German company Oventrop. The main advantage of their product is, of course, high quality. The price of a thermostatic valve from this manufacturer starts from 1,000 rubles.
- The second well-known manufacturing company is Danfoss. The company is Danish, and the cost of their products starts at 1,500 rubles. A distinctive feature of their product is that they use the latest technology for production, which allows to increase the service life of the valve.
- The last of the three well-known representatives was the Italian company Luxor, which stands out from the rest with its prices - from 250 rubles, and is also characterized by the fact that the products from the manufacturer are quite reliable.
Installation Recommendations
The installation of this product is best followed by the following recommendations:
- The most appropriate place for installing the valve is the entrance to the heating radiator.
- It is important to know that there is such a parameter as the optimal installation height of this device. It is in the area from 40 to 60 cm from the floor. Most often, all valves are initially calibrated to that height. If you cannot follow this rule, then after installing the device you will need to reconfigure it.
- In order to ensure the normal operation of the sensor, it is necessary to follow one more recommendation - the valve head should be horizontal after installation. If you position the device so that the head is in a vertical position, then warm air flowing through the pipes will interfere with the normal operation of the valve.
- Another rule is the arrangement of the bypass in the event that the valve is mounted in a one-pipe system. A bypass is a pipe through which liquid will circulate if, for any reason, its movement in the radiator itself is difficult.
Valve connection
You can connect a thermostatic radiator valve following the scheme:
- The first thing to do is to drain the fluid from the heating system. It is not difficult to do this in a private house, but in an apartment building you will have to contact a service company, since the drain valve is located in the basement of such a house.
- Next, the process of tapping into the pipe in a pre-selected location.
- At the ends of each pipe, thread the required parameters.
- If the valve thread was initially treated with a sealed thread, then using the adjustable wrench, you can install the device in a prepared place.
- It is important to note that each valve has direction-determining arrows that indicate fluid movement. When installing the reverse side, proper operation of the device will not be ensured.
- After installing the components, it is important to check the system for leaks.
- The last step is to configure the thermocouple of the system itself.
It is worth noting that if you have the necessary knowledge and skills, you can carry out installation on your own.
Product Features Danfoss, Eagle
The Danfoss expansion valve is distinguished by its design and other features from other valves. In terms of design, this device includes a thermostat, which is separated from the valve itself by a membrane. In addition, one of the important elements of these valves is the spring. It carries out the process of regulating overheating.
If we talk about Eagle products, we can distinguish the following regulator. Radiator thermostatic valve Eagle 302-1608. It has internal as well as external threads. It is characterized by such pressure as 1.6 MPa or 16 kgf / cm 2 . The type of this regulator is straight.
All Danfoss products are divided into several categories:
- TE5-TE55. These devices are designed to regulate the flow of liquid refrigerant into evaporative devices installed in refrigeration units.
- TGE. This group of products is distinguished by the fact that the design of the valve units of the device is indispensable, and they were made specifically for the air conditioner. Thermostatic expansion valve in this category is intended for commercial air conditioning systems, which are characterized by high power.
Benefits of Danfoss
A separate point deserves AKV thermostatic devices from this manufacturer. They found the most active application among refrigeration units, which are located in shopping centers. Among the most important advantages of this product are the following:
- The design of this design is collapsible, which makes it possible to easily cope with this task when the need arises, such as replacing the valve assembly.
- One of the main advantages is the absence of the need for constant adjustment of the regulator during its operation.
- This device at one time is not only a thermostatic valve, but also a solenoid valve.
AKV controllers also differ in that they have a functional electric drive. The principle of operation of this valve is based on pulse-width control of parameters.
Principle of operation
The expansion valve installation is considered the best solution for regulating the supply of refrigerant to the evaporator. The principle of operation of the thermostatic valve is based on regulating the flow of refrigerant so that overheating is observed almost all the time at the outlet of the evaporator. In those moments when the superheater of the evaporator increases due to the heat load, the regulator increases the flow of refrigerant until the superheat value falls below the set point. This adjustment method allows the device to maintain the evaporator fill level at that which is limited by the onset of the set point.