Chillers for water





The main purpose of a water chiller is to reduce the temperature of water to a point where it can be used to produce cooling effects in conjunction with other HVAC components. Water chillers are the foundation of HVAC cooling systems. They are refrigeration devices that produce chilled water (approximately 7°C to 12°C). The output of a water chiller is water at a lower temperature, typically around 10 o C depending on the Chiller design. A water chiller is similar to another refrigerator unit, except instead of keeping your food cool or generating ice, it creates chilled water.


Along with other fundamental components, HVAC water chillers play a critical function in any HVAC system. Chillers have drawn a lot of attention recently due to their innovative designs and enhanced performance of older systems. HVAC chillers now have improved efficiency and lower operation and maintenance costs thanks to new designs. For new chillers, energy efficiency and accurate load or capacity control are also desirable qualities. Although we see chillers with the aforementioned capabilities on the market, as engineers we expect to see more with improved designs at lower O&M costs. A chiller is an integral component of any HVAC system. To meet the varied demands for HVAC chillers, chiller manufacturers have also increased their manufacturing and design capacities.


Basics of HVAC Chillers


Vapor compression chiller functionality

A vapour compression or vapour absorption cycle is used by an HVAC chiller. Refrigerant passes through a chiller's evaporator, compressor, condenser, and expansion valve during a vapour compression cycle. Each of the chillers listed above engages in a thermodynamic process. Below is an explanation of how vapour compression or compression chillers theoretically work.


In the evaporator, heat is added to the refrigerant (1-2):

Refrigerant vaporises in an evaporator by absorbing heat from cold water, fulfilling its primary function. Vaporized refrigerant exits the evaporator, but chilled water is produced on the other side. As a result, heat is removed from cooled water while refrigerant is given to it at constant pressure. In an evaporator-like shell and tube configuration, the refrigerant and chilled water are kept separate and kept from mixing by a solid wall.


Refrigerant vapours are compressed in the compressor (2–3).



The Operation of Water Chillers:

The evaporator releases refrigerant vapours, which are then compressed to high pressure and temperature by the chiller compressor. Compressors need energy input to function, thus electricity is provided to them.


Refrigerant in the condenser (3-4) 

rejects heat in the opposite way from the evaporator. The refrigerant rejects heat to an external cooling liquid or to the air. In this method, outside media is heated while refrigerant is condensed. Cooling towers can be used to cool external media like cooling water, which can then be recycled back into the condenser.


Refrigerant expansion in the expansion valve (4-1)

Condensed refrigerant exiting the condenser is expanded in the expansion valve, and then its pressure and temperature are decreased to the evaporator's level so that the cycle described above can be repeated.

The evaporator, one of the four hvac chiller components listed above, is where chilled water is produced following a heat-refrigerant exchange.


Must Read: Electric (Compression) Chillers vs. Absorption Chillers






Click here to fb profile:



Click here to visit website:








You have to wait 10 seconds.