What's the difference between air cooling and water cooling?

The so-called air cooling, as the name implies, is to use wind as a heat dissipation medium, but the medium is actually air. Low efficiency, convenient installation and small floor space.

Then water cooling means using water as a heat dissipation medium. High efficiency, large area, need to install professional cooling tower.

Comparison of refrigeration performance of (1)

The condensation temperature and pressure of air-cooled chillers depend on the outdoor dry bulb temperature. The condensation temperature and pressure of water-cooled chiller depend on the outlet temperature of cooling tower.

(2) Economic comparison of operation

When the water chiller runs in the air conditioning season, the main cost difference will occur in the power consumption because the cooling water of the water chiller is basically circulating water.

(3) Thermal power comparison of units

Because air cooled chiller condenser exchanges heat with air, the heat storage capacity and thermal conductivity of air are far less than that of water. In order to facilitate heat dissipation, the condenser of the air-cooled unit must have a large heat exchange area, which leads to the huge volume of the air-cooled unit, which is about 3 ~ 4 times larger than that of the water-cooled unit with the same refrigeration capacity, and its weight is much heavier than that of the water-cooled unit.

(4) Comparison of computer room requirements

In the water-cooled scheme, the cooling tower and cooling water circulating pump can be set in the open air on the roof, and the refrigeration system is generally required to be set in the machine room on the equipment floor. Take the first-stage project of Fuhui Garden as an example: the unit with a refrigerating capacity of 770 kW covers an area of about 7 m2, and the chilled water pump and piping system covers an area of about 20 m2.

Extended data

(1) One machine has multiple functions, which can not only provide indoor refrigeration/hot air conditioning, but also provide domestic hot water all day, and is not affected by climate change, which not only saves the investment and operation cost of hot water boilers, but also avoids the dependence of solar water heaters on climate.

(2) Energy conservation and environmental protection. The heat recovery device can recover the condensation heat of the unit to produce hot water, which not only saves energy consumption, but also avoids the thermal pollution caused by the discharge of condensation waste heat into the air and the greenhouse effect caused by carbon dioxide generated by boiler combustion.

(3) Save space. The hot water supply device of the heat recovery unit is generally built in the unit, and there is no need to provide any additional installation space for the heating equipment.

(4) Stable and reliable. Because there are no moving parts in the heat recovery device, the equipment runs stably and reliably, and there is no need to invest a lot of operation and maintenance personnel. At the same time, because there is no need to add other large-load electrical control equipment, the impact on the system power grid when the equipment is started and stopped is small, which not only saves the cost of circuit equipment but also reduces potential safety hazards.

Baidu Encyclopedia: Characteristics of Wind, Cold and Heat Recovery