Capillary tube and limiters
Variable outlet of expansion valve may be replaced, in small systems, a long thin tube. This is not modulating devices and has certain restrictions, but gives enough of effective management in a wide range of conditions, if properly select and apply. The mass flow is a function of the pressure and the degree of supercooling of the liquid on the record. Capillary tube is used almost exclusively in small and air-conditioning systems of self-regulation within certain parameters. Increasing ambient temperature results in an increased load on air conditioning and condensing pressure will grow, forcing more of the refrigerant flow.
Tube holes of 0,8-2 mm, length 1-4 m of the total. The capillary tube is only installed at the factory built and tested equipment, precision refrigerant charges. This is not applicable for the installed system.
The restrictor, an expansion device overcomes some of the limitations of the capillary tube. Holes can be precision-drilled during the capillary may suffer due to the difference between the inner diameter from their length, which leads to changes in the projected figures.
Fig. 8.6 shows how the device is used in reversible air-conditioning. Figure 8.6(a) the device is shown in the normal cooling mode. The bullet, which can freely move horizontally on a small number of the assigned place to make the refrigerant through the Central limit, which acts as an extension to the device. If you change the thread Fig. 8.6(b) , the bullet moves to another place, but grooves enables flow around the outside, and through him, so the limit is very small.
It is typically installed on the outlet of the condenser, and not on the evaporator. This means that instead of the liquid in the evaporator, the pipe contains liquid and gas flow and should be isolated. While the warmth take it negatively affects the performance, pressure drop, which is used to drive the liquid will usually take place, the expansion valve in any case. Liquid line in remote evaporators split-systems can be quite lengthy and high pressure in the liquid line of the type usually used more, the pressure drop can lead to increased pressure on the condenser and the tendency to form bubbles. Restrictions-tor can be presented as part of the condensing unit and is removable, allowing to make changes to ensure optimum performance....