What are the differences between water cooled & air cooled chiller in HVAC?

An air-cooled chiller has a condenser that is cooled by the environment air. The air-cooled chillers are preferred for small or medium installations but lately the quality improvement in their structure, allows the usage, in modular type, for large installations also. An air-cooled chiller is preferred especially in cases that there is not enough water or the water is very expensive. The water-cooled chillers have water cooled condenser connected with cooling tower and are usually preferred for medium and large installations where there is sufficiency of water. In addition, they are also preferred in cases that is demanded constant performance of the system, independently of the ambient temperature (industrial air conditioning, air conditioning of digital systems etc), because the capacity of the water-cooled chillers are not affected by the ambient temperature fluctuations.

Air Cooled Chiller:-

   1. In air-cooled chillers have condensers which are cooled with ambient air.

   2. In this type, an air-cooled condenser has outside air passed over it and             the refrigerant in the coil is cooled directly  by the air

   3. In Tube’s --- Refrigerant Will Flows

        In Shell --- Water Will Flow.

Water Cooled Chiller:-

   1. It uses water to transport the heat rejected in the  condensers and it                   happens when the water is cooled in a cooling tower.

   2. In Tube’s --- Water  Will Flows

        In Shell --- Refrigerant Will Flow

Note: - According to the client or customer need we have to select to install which type of chiller is going to install on the site.

PARAMETERS

AIR-COOLED CONDENSER

( Air Cooled Chiller)

WATER-COLLED CONDENSER

( Water Cooled Chiller)

1.      Water loss

Nil

High

2.      Space requirement

Low (high above TR)

Low

3.      EER (energy efficiency ratio)

Low

High

4.      Initial const

Low

High

5.      Operating cost

Low

High

6.      Maintenance

Low

High

* Water cooled chiller:

- the cooling of chiller condenser depend on water.

- it has extra cooling net work with a pump for circulation and cooling tower to decrease cooling water temperature, you have to provide makeup water source for the cooling water net work

- mostly used for large capacity cooling plants , district cooling.

- not preferred to use in desert condition because of the highly need of water.

*  Air cooled chiller:

- the cooling of chiller condenser depend on air.

- no need for extra cooling net work.

- mostly used for small and medium capacity, it is suitable for one building.

- it is preferred to use in desert condition.

• Initial cost of air cooled chillers is lower than water cooled chillers as air cooled systems don’t require cooling towers,condenser water pumps and associated HVAC components.