What is an HVAC system? What are the Parts of an HVAC system?

The full form of HVAC is Heating Ventilation and Air conditioning. HVAC plays a very precious role for maintaining indoor environment conditions. HVAC system is a technology used to maintain indoor air temperature, humidity, and air quantity. It helps to keeping us from warm during the summer season and keeping us from cold during the winter season.
The HVAC system is very far from AC (air conditioning). I will explain How it is?
To understand HVAC First, we need to understand the term Heating, Ventilation, and Air conditioning

Heating: -

Heating Means the addition of heat energy to a system. Basically, heat is added to the system by the heater, hot water. An electric heater is commonly used in AHU. Electric Heater is installed in AHU to maintain Humidity. When air is passed from the coiling coil by losing some amount of humidity then heat is added to the system(this is also called sensible heating). which increase the temperature of air from 11-degree Celsius to 16 degrees Celsius.

Here are some heating Equipment:
Heater
Boiler
Furnace
Heat pumps etc.

Ventilation: -

Simply, Ventilation is known as fresh air unit. There may me a cooling unit or may not depend on requirements of client. The ventilation unit is the same as Air handling unit difference is only parts. in ventilation unit there is only motor and pre filter, but in air handling unit there must be prefilter cooling coil. heater, motor, and fine filter.

Air Conditioning: -

The full form of AC is Air conditioning. Conditioning means treating of air to maintain indoor condition. Like filtration of air, removing moisture from air, adding heating to the air is called conditioning of air in HVAC.
Application of HVAC system (where HVAC system is used).
HVAC system is used in industries not in Residencial building because the installation cost is high and installation of the HVAC system require more space. Normally in residential building comfort AC is used like split ac, cassette AC etc.
HVAC system is used in Industries like Pharmaceutical Industries, Manufacturing industries, R and D labs, research centers, Textile Industries and many more.
The purpose of installing of HVAC system in these industries is to maintain indoor condition like temperature, humidity, Differential pressure, and to maintain class of area.
Some area like Airport, Wearhouse etc HVAC system is installed and that type of HVAC system is call comfort HVAC system.
The main purpose of installing core HVAC system in pharmaceutical sectors is to maintain cleanness of class in industries. In Pharmaceutical sector different type of medicine is manufactured to protect medicine from rejection from they need to maintain indoor condition.

Parts of HVAC system: -

1. AHU
2. Compressor
3. Condenser
4. Thermal expansion valve
5. Terminal units
6. Chiller
7. Duct system
8. Electrical panel
9. BMS system
10. Heating system

AHU: -

AHU stand for air handling unit. In HVAC system AHU is main parts of whole system.
AHU is an air handling machine, which is used to regulate or handle or circulate air to different areas. AHU having different chamber or compartments like Mixing chamber, filter section, cooling coil chamber, heater section, motor section, UV light section.
Air is from area is suck through duct and supplied to same area through supply air duct. When air enter in to ahu through return air duct the air is mixed with fresh air, then passed to filter section, after filtration it passed to cooling coil section to cool, here some moisture is also removed from air, then passed to heater section for the addition of sensible heat. After adding heat, it passed to motor section and that motor is pull air through fine filtration to supply air duct.

Compressor: -

Compressor is the part of outdoor unit. In HVAC system compressor is used for the compression of refrigerant gas. The compressor also helps the gas to circulate through pipe. Compressors help to maintain the motion of refrigerant gas.

Condenser: -

Condenser is also prat of outdoor unit. It help to remove heat from refrigerant which is circulation through pipe.
Condenser is made of combination of copper pipe and aluminum fins. When refrigerant gas is compressed, the heat is extracted from that gas, to remove that heat, system need more contact area, so that heat can be easily transferred to surrounding area. To increase the velocity of that contact area. Single phase fan is installed.

Thermal expansion Valve: -

The thermal expansion valve is part of RAC cycle. It help to modulate the discharge refrigerant gas with the help of suction refrigerant gas temperature. The thermal expansion valve modulate according to the suction temperature.

Terminal units: -

In HVAC system, HEPA filter, diffuser is known as terminal unit. In pharmaceutical sector mainly HEPA filter is used. In non-classified area diffuser is used.

Chiller: -

Chiller is one of most important part of HVAC system. Chiller is used to provide cooling to HVAC system. Chilled water is flow through expansion coil which is mounted in AHU. Which reduce the temperature of air.

Duct system: -

Duct is used in HVAC system to flow air in specific area to get temperature. There are different type of duct is used in HVAC systems. Like Circular duct, rectangular duct, oval shape duct. These all duct is made of GI sheet. The sheet may be 18G, 20G, 22G, 24G etc, depend on client requirements and design.

Electrical Panel: -

Electrical panel help to control the whole system by interlocking all unit with AHU. Electrical panel is made of different interlocking and control wiring to interlock complete system.