What are the key components of a typical centralized allair

What are the key components of a typical centralized all-air HVAC system? Write the component name and their corresponding function/role. Based on the heat transfer media, HVAC systems can be classified into how many systems? Which system is the most popular system and why? Compared with the all-air system, what are the advantages of all-water systems? What are the disadvantages of all-water systems?

Solution

1) The key components used in a typical centralised all HVAC system are air compressor, condenser, expansion valve and evaporator.

Compressor is used to drive thermodynamic refrigeration cycle or in a free cooling system which uses pumps to circulate a cool refrigerant.

Condenser is used to condense a substance from gaseous to liquid state.

Expansion valve also known as metering device regulates refrigerant liquid to flow at a proper rate.

Evaporator is used to evaporate liquid refrigerant as it absorbs energy from inside air, returns to compressor and repeats the cycle.