HVAC SYSTEM

Explaining the HVAC System :

The component of HVAC System :

1. Refrigerant cycle 
2. Chilled Cycle 
3. Condenser Cycle 

The first circuit [Refrigerant cycle] :

it's Freon circuit and consist of :

• Compressor
• Condenser 
• filter drier 
• expansion valve 
• Evaporator

The Compressor :

It's a type of rotary compressor. It's a screw compressor that pulls the refrigerant gas from the evaporator, raises its pressure and temperature, and compresses it to the condenser. This is done through a rotary movement of the mechanical part, which consists of a fixed part and a moving part that rotates around itself via a rotating shaft. .

Condenser :

It is a tank that is immersed in a refrigerant compound. The refrigerant compound enters from the top in the form of a gas and exits from the bottom in the form of a liquid. This change occurs as a result of heat exchange between the refrigerant compound coming from the compressor and the water pipes located inside the tank through which the water passes at a low temperature that comes from the cooling tower. As a result of this heat exchange, condensation of the refrigerant occurs.

Filter of dryer :

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It is used to trap impurities and absorb moisture from the cooling compound.

Expansion valve :

It works to control the feeding of the evaporator from the refrigerant compound according to the need. In the event that the load on the evaporator increases, it will need a large amount of the refrigerant compound and vice versa. It can be said that its main function is to reduce the pressure of the refrigerant compound through the process of throttling.

Evaporator :

One of the most important components of the coolant is the coolant. The cooling compound enters in the form of a liquid coming from the valve, and a heat exchange occurs between the pipes in which the cooling compound is present and the water that enters the tank. As a result of this heat exchange, the water is cooled and is pushed by the pump to the Air hand unit or Fan cooled unit. The heat exchange evaporates the refrigerant compound and turns from the liquid state to the gaseous state. It exits the evaporator and is drawn by the compressor, so the cycle returns to the beginning.

Air hand Unit :

It is a passage inside which there is a fan - a cooling coil - a filter - an electric heater coil. Through the fan, air is drawn in and cooled when it is pushed onto the cooling manifold in which there is ice water. As the process continues, the temperature of the water rises from the air and is returned again to The evaporator is cooled and returned to the Air hand unit to cool the air again.

This cooled air is released to the places required for the cooling process, such as rooms and others....

There are two passages, the first is called the supply air unit, and it is through which the cooled air from the air hand unit passes

The other is called Return air duct, through which a quantity of air is drawn into the room, part of it is expelled permanently, and the other quantity is cooled.

The condenser cycle :

The Cooling Tower 

It contains PUMP, where the refrigerant compound is condensed and turns from a liquid state to a gaseous state by cooling the Freon. This is done by air entering the condenser coils or by cold water. It has openings at the top for water to enter through sprinklers and openings at the bottom for water to exit. It is returned to the condenser and a float to compensate for the evaporated water in the cycle.