One method of providing evaporator capacity management is the separation of the evaporator in the form of two or more separate partitions or chains. Each circuit individually controlled dirough own solenoid valve on the liquid line, so that it can be enabled or disabled as the load. Using this method, evaporators power can be divided on the cost-effective number of steps. The number and size of the individual evaporator sections is based on the number of steps necessary facilities along with a percentage change of power on the step.
The location of the evaporator schemes depends on the relationship die reasonable load of the total load (sensible heat ratio) in different load conditions. Sensible heat ratio (SHR) is a measure of the number of sensible heat, which is removed with a coil in relation to die the total quantity of heat is absorbed by the refrigerant. The more sensible heat ratio, the greater the difference between the temperatures experienced in the air or in the water, moving through the coil. As sensible heat ratio decreases, more moisture (latent heat) is removed using a coil.
When a person circuit is used to vary the capacity of the evaporator in the system of the SCC of the coil does not influence. Therefore, die air passing through the die active areas to die coil experiences the same changes in the diy-bulb. SHR is not affected because die of air flowing through the coil is subjected to die the same amount of heat exchange surface area. However, the temperature at coil outlet increases die conditional and unconditional flow of air at the outlet of the evaporator mix. When the depth of closure is used as the regulation of productivity, the amount of latent cooling with increasing depth active chains increases. Therefore, as one or more lines of the evaporator are opened and closed, sensible heat ratio increases.
Another mediod modulating evaporator capacity varies the amount of air flowing through the coil through the use of dampers. These flaps are set before the evaporator so they modulate open and closed to change the speed of the air flow through the fan and heat exchanger. Therefore, as die damper blade to modulate dieir closed position, the amount of air passing through the fan and heat exchanger reducing the temperature and humidity of thin air. The two flaps are joined together so that they act in unison. The person normally open valves and bypass valves are usually closed. Die system load is reduced, the person absorption modulate to its closed position, while the bypass dampers are modulated open. This strategy supports constant bit rate dirough evaporator fan even if the volume of air flowing dirough coil depends. Multispeed blowers and variable speed drives can also be used to perform similar functions...