The refrigeration heat exchangers of a chiller mainly refer to the condenser and evaporator, which are two of the four core components in the refrigeration system. They directly affect the system's heat absorption and heat release capacity as well as efficiency. Both the condenser and evaporator involve phase-change heat transfer, which is a key characteristic of these two types of refrigeration heat exchangers.
I. Classification of Chiller Heat Exchangers
Evaporative Condenser
Unlike other heat exchanger products, the evaporative condenser belongs to neither air-cooled nor water-cooled heat exchangers. It combines the advantages of both air cooling and water cooling, forming its own strong heat dissipation efficiency.
Shell-and-Tube Heat Exchanger
As a veteran product among water-cooled heat exchangers, shell-and-tube heat exchangers are mainly used in large-scale equipment such as refrigeration and cold storage systems. Due to this characteristic, if a shell-and-tube heat exchanger malfunctions and affects the entire industrial chiller system, it will inevitably cause significant losses. Therefore, strict quality requirements are imposed on shell-and-tube heat exchangers.
Finned Heat Exchanger
It has the longest development history and the widest application range among the two core heat exchangers (condenser and evaporator) in the refrigeration accessories industry. However, finned heat exchangers are prone to irreversible damage caused by external forces during long-distance transportation, so they have relatively high requirements for transportation and logistics.
Tank-Type Heat Exchanger
Compared with traditional heat exchangers, the tank-type heat exchanger has higher heat exchange efficiency, a smaller volume, and a water circuit that is easy to circulate. The water inlet of the water circuit is located at the bottom of the entire water circuit, which facilitates drainage and effectively reduces fouling.
Plate Heat Exchanger
The plate heat exchanger adopts a fluid heat dissipation method, resulting in extremely high heat dissipation efficiency of up to 95%-a level of heat exchange efficiency that is rare among products in the heat exchanger industry.
Double-Pipe Heat Exchanger
Although the heat dissipation efficiency of the double-pipe heat exchanger is only about 75% compared with that of the plate heat exchanger, it does not have the problems of easy freezing and clogging that plague tube-type heat exchangers.
II. Usage Precautions for Chiller Heat Exchangers
Properly handle the relationship between evaporation temperature, chilled water freezing point, and chilled water temperature. Ensure that the evaporation temperature is not lower than the chilled water freezing point, and try to increase the chilled water temperature to keep it away from the freezing point.
Use plate heat exchangers with better performance, whose pressure-bearing capacity is not lower than the maximum pressure controlled by the system.
Installing anti-freezing and anti-clogging devices is indispensable.
Improve the accuracy and response speed of temperature control-control not only the inlet water temperature but also the chilled water outlet temperature.
Strengthen equipment maintenance, improve the airtightness of the system, and reduce refrigerant leakage. When the equipment is not in use for a long time, the refrigerant in the system should be pumped out or pressed into the liquid receiver.
Enhance the control of chilled water flow rate and evaporator pressure drop.
Install a filter in the chilled water system.
Change the low-pressure shutdown setting to low-pressure operation protection, and switch the automatic reset function to manual reset.
The above content covers the classification and usage precautions of chiller heat exchangers. It is hoped that this information will be helpful to you.
If you need a customized heat exchanger for special working conditions (e.g., ultra-high pressure structure, titanium alloy material, multi-flow channel design), you can send an inquiry or contact us at any time. After in-depth communication, we will deliver specific specifications and technical plans for you.
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