What is a Chiller?
A chiller can be regarded as a cooling system that cools materials down by removing heat from a liquid via a vapor-compression or absorption refrigeration cycle. The liquid gets circulated through a heat exchanger to cool equipment. In a chiller system, there is always a liquid working as a refrigerant going through the heat exchanger in order to transfer the heat energy. When the heat gets absorbed by the liquid, materials get chilled.
What are Types of Chillers?
In terms of the cooling methods of condensers, the chillers can be primarily classified into water-cooled and air-cooled chillers. They have basically same components, composed of the evaporator, compressor, expansion device and condenser. But it can’t be ignored that they varies from each other, which decides their different application scenarios. Let’s cover their differences in the following.
Water-Cooled Chillers VS. Air-Cooled Chillers
As their name suggests, the water-cooled chiller takes water as the source of heat exchange, which is equipped with a special cooling tower. But the air-cooled chiller takes gas as the source of heat exchange, which is equipped with a special fan.
They works in different manners as well. A water-cooled chiller uses the cooling tower and water pump to extract hot water for heat dissipation, allowing the cooling process to circulate. But the working principle of an air-cooled chiller varies from that of a water-cooled chiller. The air-cooled one mainly uses the fan for heat dissipation.
Their installations and using methods are also different. A water-cooled chiller only can be used when its external is equipped with the water tower and pool, while an air-cooled chiller is movable requiring no water tower and pool.
For a water-cooled chiller, it requires less water and small installation area. It is easy and cheap to maintain a water-cooled chiller. But an air-cooled chiller needs more water and larger installation area. It is quite expensive to maintain an air-cooled chiller.
Is a Water-Cooled Chiller more Efficient Than an Air-Cooled Chiller?
Matched with cooling towers, a water-cooled chiller has a higher energy efficiency compared to an air-cooled chiller. In other words, a water-cooled chiller is more efficient than air-cooled one, which is especially suitable for large cooling plants, such as district cooling.
Which of Chillers Should be Chosen?
There are a great number of factors that should be taken into consideration when choosing a proper type of chiller, such as operating conditions, the materials to be cooled, availability of water and other factors. Both a water-cooled chiller and an air-cooled chiller have their own application scenarios.