Regulation Of The Temperature At The Condenser Inlet
Water chillers, which are used for cooling of large buildings typically use of cooling towers reject die of heat is absorbed by the refrigerant. The unit is designed for efficient work within a small range of temperatures at the inlet to the condenser, as described. Consequently, since the tower of the cold water temperature is a function of ambient temperature, WB, temperature and load on the system, some means of control the cold temperature of the condenser water inlet, which should be included in the system. The range of cold water temperature at the condenser inlet, usually operated by two different strategies. One strategy is to cycle operation of towers fan, die others, to regulate the flow of water inside the tower, with call diverting valve hot water pipelines.
Cooling towers can be purchased with one, two or variable speed drive motor. Fan control circuit measures die temperature of the cold water and adjust fan speed to maintain the cold water temperature is below the set point. Since the water temperature in the swimming pool or the pot increases the fan speed increases, drawing more air through the tower in order to increase the rate of evaporation, thereby reducing the cold water temperature.
Conversely, when the cold water temperature drops below the set point, the fan speed is reduced or cycled off. When the fan cycles off, evaporation process continues, but at a much lower rate. Two-position control tower fan not allow close monitoring of the cold water temperature control differential necessary in diermostat. The resulting temperature range is not acceptable for the majority of the new chiller applications. Thus, diverting valve, as a rule, included in the system, to achieve closer monitoring die temperature of the cold water.
Diverting valve device with the ability to connect three pipes. Valve has one input port and two outlet ports are managed by the unit, which can place the plug connector somewhere between 0 and 100%. The input port is connected to a hot water pipe, leaving the condenser. One of the output ports are connected to a hot water pipe leading to die tower, and the other is passed in the cold water pipe return water from the tower. Pipe tee is used to allow the mixing of cold water returning from die tower with hot water withdrawn from the tower crane. Water outlet splitter is connected to the inlet to the condenser, to complete the cycle.
Sensor control circuit measures the water temperature at the condenser inlet. If the temperature is below the desired setpoint controller position to divert valve so that more hot water bypasses the tower and mixed with the return of cold water to raise its temperature before it enters the condenser. Conversely, if the water temperature at the condenser inlet, too warm, the valve is located controller so more water diverted to the tower, increase of volume of cold water returning to the condenser. Valve modulated various positions, to allow the control loop to make gradual changes of water temperature at the condenser inlet. Many of the towers use both strategies to improve the operational efficiency of the entire system...
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