Types of Air Conditioning

In this world, we all are aware that the environment is not the same for all. There are countries with extremely hot weather, and some have the coldest weather. Citizens who live in hot weather countries with extremely high temperatures suffer from various problems like skin irritation, burning, discomfort in living, and also causes tanning. To prevent this severe situation, they use an air conditioning system. But have you ever thought about how these system works and how many varieties are there in the market? This article will explain Air Conditioning, its principles, the Refrigeration cycle, and ventilation in depth.

Air Conditioning (AC) is a technology that increases room comfort by changing the temperature and humidity of the room environment. This technology is used in various places, including offices, homes, vehicles, and many other things, to make a favorable environment. The main goal of AC is to maintain and control the hot air that is present in the environment.

What is an Air Conditioning?

It is the process of changing the qualities of air present in the surroundings, such as humidity and temperature, to create favorable conditions.

Air Conditioner

In other words, AC is a technique that develops and maintains certain temperature (mostly we use 16 degree celsius), relative humidity, and air purity conditions in indoor areas. This procedure is commonly used to maintain a degree of personal comfort. It is also used in industrial applications to ensure the proper operation of equipment or machinery that must operate in specific environmental conditions or for carrying out certain industrial operations, such as welding, that generate large amounts of heat that must be disposed of in some way. An air-conditioning system must be successful and independent of outside climatic conditions and requires control over four essential variables: air temperature, humidity, movement, and quality.

The boundary between industrial and personal comfort applications is not always obvious. Industrial AC generally needs more accuracy in temperature and humidity management. Some applications require a high level of filtration and contamination elimination.

Comfort air-conditioning involves more than just meeting personal temperature-humidity requirements; it also includes architectural design, weather forecasting, energy consumption, and sound emissions in order to imitate the perfect environment for human psychophysiological well-being.

Working Principle of Air Conditioning

Its works like a pump, an air conditioner draws heat from a space and releases it outside. It consist Heat exchanger coil, compressor, and a mechanism that use refrigerant gas in the operation. There is an absorption of heat during the transition from a liquid to a gas is a basic concept of physics that underlies the operation of air conditioning equipment. Practically, AC move heat from a room’s inside to its outdoor.

Working Principle of AC

• The refrigerant initiates as a low pressure, low temperature liquid in the evaporator coil of the house. Here, the heat from the room air is absorbed. In the meantime, heat absorption causes the refrigerant to change from a liquid to a low-pressure gas. The unit outside the home receives this gas after that.
• Here, a compressor is utilized to raise the temperature and pressure of this gas refrigerant.
• It is then moved to the condensation coil, which discharges the heat that was previously trapped inside your house into the atmosphere. A fan pushes air across the condenser for cooling and turning the refrigerant into a high-pressure liquid.
• The cycle is then continued by reintroducing the refrigerant through the expansion valve into the house.

As a result, the heat (hot air) within your house is moved outside while promote cooling.

Components of Air Conditioning Systems

• Evaporator-An evaporator consists of a heat exchanger coil that gathers heat from a room’s surface. Because it is the part where the fluid refrigerant receives heat from the surrounding air and turns into a gas, this part is called an evaporator. Copper and aluminum are commonly utilized in construction because of their better heat conduction properties. Copper tubes in the evaporator transport the refrigerant, and vents attached to the tubes improve heat transmission from the refrigerant to the surrounding air.
• Refrigerant– When a gas moves through the AC’s heat exchanger coils, it absorbs heat from the air around it and releases it outside. An AC’s refrigerant evaporates and condenses, reducing the temperature of the indoor air.
• Condenser– In this part hot gas condenses into a liquid, thus the name. When the high-temperature gas reach to the condenser and pushes air over the heat exchanger, a spinning fan cools the gas and transforms it into a fluid. Condensers, like evaporator units, are commonly made of copper or aluminium. However, they are housed in a facility outside the space.
• Compressor– It compress the gas to extremely high pressure. It acts as pump cooling gas from the evaporator to increase temperature. After that high pressure gas is then sent to outside chamber.
• Expansion Valve-The expansion valve, located between the condenser and evaporator, is an essential component in AC systems. It keep the amount of refrigerant in evaporator. Expansion valve converts the high-pressure refrigerant in the condenser into a low-pressure. The evaporator then continues to operate using this low-pressure, low-temperature liquid.

Refrigeration Cycle

The cycle has 4 basic processes: compression, condensation, expansion, and evaporation. The cycle is illustrated in the diagram below.

Vapor-Compression Refrigeration Cycle

• Compression process – It is like the engine of the cycle. The compressor draws the superheated refrigerant vapor through the suction pipe and begins compressing it. The pressure, temperature, and energy of compressed vapor rapidly rise. In contrast, the specific volume was greatly reduced. At this stage, the temperature and energy of refrigerant vapor are the highest in the whole cycle. It produces very hot and high pressure vapor during this process.
• Condensation process – Now here condenser job comes into play, it turns gas into liquid or we can say it condense the refrigerant. It is done whenever the outdoor air flows through the condenser’s coil which is filled with hot, gaseous refrigerant. It leads to the transfer of the heats from the refrigerant to the cooled outdoor air where the diffusion of excessive heat to the atmosphere takes place. The condenser coils run through the condenser, increasing the surface area of the pipework and heat transmission to the air. Because of the high pressure and temperature decrease, the refrigerant converts from a vapour to a hot liquid.
• Expansion process – The refrigerant then reaches the expansion mechanism in a heated, high-pressure state. The expansion device functions as a catalyst, rapidly reducing the refrigerant pressure and enabling it to boil more easily in the evaporator. The expansion device’s main purpose is to lower refrigerant pressure. Because the pressure decreases so quickly at the expansion mechanism, the refrigerant transforms into a mixture of cold liquid and vapor.
• Evaporation process – When the refrigerant becomes a cold mixture of liquid and gas (vapor), it starts moving through the evaporator. When the refrigerant has chilled to a cold combination of liquid and gas it starts moving through the evaporator. The evaporator cools the ambient air by boiling (or evaporating) the refrigerant that flows through it. This occurs when warm air passes over the evaporator coil while cold refrigerant flows through it.

Heat flows through the air to the refrigerant, which immediately cools the air before venting it into space. The evaporator coil, like the condenser coil, wraps around the evaporator to optimize heat transmission from the refrigerant to the ambient air. The heated air aimed to the evaporator quickly boils the low-pressure fluid refrigerant, which flows to the compressor as a cold gas or vapour.

Types of Air Conditioning

There are many types of air conditioners for homes, ranging from massive central systems powered by external compressors to small plug-in units that may be installed in windows or on the floor.

Because each air conditioner has advantages and disadvantages, you may use this guide to choose which air conditioner is ideal for you, depending on these factors.

There are some list of Air Conditioning given below :

• Window Air Conditioners
• Central Air Conditioners
• Portable Air Conditioners
• Hybrid Air Conditioners
• Geothermal Heat Pumps
• Package Terminal Air Conditioners (PTAC)
• Ductless Mini-Split Systems
• Floor-Mounted Air Conditioner
• Smart Air Conditioner
• Evaporator Cooler

Window Air Conditioners

Given below is the image of Window Air Conditioners

Window Air Conditioners

A window air conditioner is categorized as a “unitary” air conditioning system. It comprises of a single air conditioning unit installed in a window or, less commonly, through a hole in an outside wall.

The whole refrigeration system is housed in a single, small box that is an air conditioner window. The condenser coils on the appliance’s outside are where heat is ejected. The air cools the space with the evaporator coils on the interior side it blows into it.

Generally, room moisture condenses on the evaporator coils and drops to the floor from a tray on the appliance’s underside. For this reason, a window air conditioner needs to be mounted with a very tiny tilt towards the outside.

Certain air conditioners have the potential to leak water onto the inside floor when they are positioned incorrectly. Window air conditioners may cool a single room or an entire floor and are available in a variety of sizes. A tiny house, especially one that is one story, may be able to be completely cooled with a big window air conditioner. It’s also a cheap option that requires little installation.

Advantage of Window Air Conditioners

• It is useful for cooling a room or even small house.
• It is easy to install.
• It is less expensive.

Disadvantages of Window Air Conditioners

• It is not suitable for large space.
• It can accumulate moisture on the floor.

Central Air Conditioners

Given below is the image of Central Air Conditioners

Central Air Conditioning

A central air conditioning system is the largest and most expensive form of conventional air conditioning system. It is made up of two units: the evaporative unit and the condensing unit, which are connected by refrigerant tubing. The evaporative unit is typically installed in the plenum, which is the huge central chamber between the furnace and the duct system, implying that your air conditioning system use the same ductwork and blower fan as your heating system.

For cooling entire homes, central air conditioners are usually the most efficient kind of air conditioner. Making sure the new central system is the right size for your house is the most important thing to think about while installing it. A too-big system will not function properly and will not sufficiently dehumidify the indoor air. It won’t cool down sufficiently if it’s too tiny. A central air conditioning system’s proper maintenance is equally crucial and frequently calls for a specialist.

Advantage of Central Air Conditioners

• It gradually increases cooling in entire home.
• Noise producing component can be placed outside the house.

Disadvantages of Central Air Conditioners

• It has a complex installation
• It is expensive than window A.C.
• House area should be consider while purchasing.

Portable Air Conditioners

Given below is the image of Portable Air Conditioners

Portable Air Conditioners

Another kind of unitary air conditioning system is a portable air conditioner. The air conditioner is a movable, standalone device that is set up on the floor of a room. It uses an external vent to release exhaust heat through a window or wall vent outside. These units are louder than other kinds of AC systems since the evaporator and condenser coils are housed in the same box, just as in a window air conditioner. These Conditioner are useful and efficiently work in 500 square feet. They are often used for short-term space cooling or in situations where installing a window-mounted unit is impractical.

The evaporator fan of the portable unit operates quite continuously because it is indoors and must remove condensed moisture that builds up within the unit. Additionally, units may feature a reservoir to hold condensed water, which has to be frequently drained. Compared to a window-mounted device, where collected moisture just drops onto the ground, this is very different.

Advantage of Portable Air Conditioners

• It can be located where cooling require.
• It is affordable and easy to setup.

Disadvantages of Portable Air Conditioners

• It is not suitable for large spaces.
• It produces lots of sound.

Hybrid Air Conditioners

When we discuss hybrid systems, we usually mean replacing the pipes that carry refrigerant with pipes that carry water. Working together with chilled water and refrigerant comprise a hybrid system.

A hybrid heating system has both benefits of an electric heat pump to provide maximum comfort and efficiency in both warm and cold seasons, providing you more control over your electricity expenses. As the outside temperature changes, the system automatically shifts between a heat pump and furnace to use the cheapest fuel source while maintaining maximum efficiency. Furthermore, because the system is so efficient, heating expenses are often lower than those of a standard gas furnace.

Refrigerant is often stored in the outdoor condensing unit and connected to a branch box that uses the energy from the refrigerant to create water to service the indoor units.

Advantage of Hybrid Air Conditioners

• The refrigerant system requires far less refrigerant to function properly when we replace some components of it with water.
• There is a lower chance that a leak may pose a health danger since the building lacks refrigerant pipes.
• They work well in retrofit environments.

Disadvantages of Hybrid Air Conditioners

• Compared to heat pumps or traditional air conditioners, hybrid air conditioners often have a greater initial cost.
• To guarantee correct sizing, positioning, and integration with current HVAC systems, hybrid air conditioners need to be installed by professionals.

Geothermal Heat Pumps

Given below is the image of Geothermal Heat Pumps

Geothermal Heat pumps

In geothermal HVAC system, heat revolves around the house. It mainly uses two parts i.e, heat pump and underground pipe.

The house can be heated or cooled by the circulation of a liquid combination that acts as a heat exchanger. The heat pump functions like an air conditioner, drawing heat from your home into the ground to cool it down. To keep your house cool in the summer, the earth essentially serves as a heat sink.

These are the system that uses earth, groundwater, or water on the surface as a heat source or sink. They are also known as ground source heat pumps or geo-exchange. These systems are known as surface water heat pumps, groundwater heat pumps, and ground-coupled heat pumps, depending on how they are configured. It consume 25% to 50% less power in comparison to traditional heating and cooling systems.

They are less dependent on the outside air temperature, need less maintenance, last longer, and are quieter than air-source heat pumps. The cost of using fuels such as natural gas, electricity, or other utilities might influence the choice to use this technology.

A Geothermal Heat Pumps consists of several components including

• Heat pump
• Ground Loop
• Air delivery system

Heat pump	Ground Loop	Air delivery system
The heat pump takes heat from the fluid in the pipe, compresses it, and then transfers it to the building during the winter.	It is a network of pipes called the “ground loop” which is buried close to the structure in the muddy ground. To absorb or release heat from the earth, a fluid moves through the ground loop.	The air distribution system distributes warm or cooled air throughout the structure using traditional ductwork or pipe systems.

Advantage of Geothermal Heat Pumps

• It is very effective in humid areas.
• It can be installed in both new constructed place as well as retrofit scenarios.
• It has low electricity consumption.
• It requires low maintenance.
• It is best source of heating and cooling.

Disadvantages of Geothermal Heat Pumps

• Heat pump has to replaced after 20-25 years.
• It is often expensive and has limited location for installation.
• It takes five to ten years to recover the substantial installation costs.
• Possible problems with ground water.

Package Terminal Air Conditioners (PTAC)

Given below is the image of Package Terminal Air Conditioners (PTAC)

Package Terminal Air Conditioners (PTAC)

The term “packaged terminal air conditioner” (PTAC) refers to a particular kind of independent heating and cooling system that is designed to be installed through a wall. Chrysler Motors engineers created the first useful semi-portable air conditioner. A PTAC unit and ductless mini-split work on similar principles. They both operate on particular areas rather than entire buildings and can chill and heat using a reversible heat pump. Alternatively, ductless mini-splits link interior and outdoor units via a network of refrigerant lines. That refrigerant enables mini-splits to both cool and heat the interior air.

If you use a PTAC unit without heating, you may utilise both in the same place, thus they are not mutually incompatible. The main benefit of PTAC over ductless mini-splits is ventilation. Mini-splits cannot ventilate the air since they only flow refrigerant between the units. This is a challenge when attempting to fulfil construction rules and specialized criteria. The correct PTAC unit can accomplish all three: heat, cool, and ventilate.

A mini-split, on the other hand, does not necessitate a hole in the wall, which is often required in some structures. The mini-split just requires an aperture wide enough for the little refrigerant lines to pass through to link the interior and outdoor units. The decreased gap also contributes to higher cooling efficiency. Both solutions can be effective in ductless situations, but a PTAC offers superior ventilation and an all-in-one solution.

PTACs are frequently found in multifamily structures (senior housing, condominiums, apartment complexes), as well as commercial contexts (hotels, motels, hospitals). While most PTACs are used to chill individual rooms, certain models also have heat pumps and/or resistive heating. It would be more appropriate to refer to packaged terminal heat pumps or PTHPs. There are also PTACs that support natural gas heating or hydronic heating coils for exterior heating.

Advantage of Package Terminal Air Conditioners (PTAC)

• It provide individual control of temperature to every room.
• It is easy to install and has excellent performance.
• It is affordable to use.
• It provide better air quality.
• It has better energy efficiency.

Disadvantages of Package Terminal Air Conditioners (PTAC)

• It is not efficient in comparison to split-system.
• All the component has to be placed outside the house resulting in corrosion.

Ductless Mini-Split Systems

Given below is the image of Ductless Mini-Split Systems

Ductless Mini-Split Systems

The air conditioning system is divided into two packages, or terminal units, by the split system, often known as a “mini-split” or ductless system. Included in the condensing unit, which is external to the structure, are the compressor, condenser, and condenser fan. The air conditioning and distribution are managed by the evaporative unit, which is situated within.

Usually situated high on an interior wall, this rectangular box unit has an evaporator coil, expansion valve, and circulation fan. The wall that separates the evaporative and condensing units is where the refrigerant tubing goes. Water that condenses from the indoor evaporator coils is drained away via a secondary tube that runs parallel to the refrigerant tubing. Split systems are frequently seen in multi-unit structures like hotels and residences. It has grown in popularity in the homes that does not have an air conditioning system, including those with electric or hot water steam radiator heating.

Advantages of Ductless Mini-Split Systems

• It is less expensive than a HVAC system.
• It can facilitates both heating and cooling in the house.

Disadvantages of Ductless Mini-Split Systems

• It has a complex installation process.
• It is not a good choice for renters because it is complicated to remove.

Energy Efficiency

The energy efficiency ratio  measures the effectiveness of room AC. The EER is the proportion of cooling capacity to power input. The higher the EER rating, the more efficient the AC. When buying a new room AC, look for the ENERGY STAR designation.

Ventilation and Air Quality

Ventilating, or ventilation (the “V” in HVAC), is the act of switching or replenishing air in any area to maintain acceptable indoor air quality. It comprises temperature control, oxygen replenishment, and the elimination of moisture, odours, airborne bacteria, heat, dust, smoke, carbon dioxide, and other contaminants.

Floor-Mounted Air Conditioner

Floor-Mounted Air Conditioner is type of cooling system that is installed on the floor rather than than being mounted on the wall. These units are placed on the floor against a wall or near windows or in corners of rooms. They comes into different shape and capacity according to the users requirements. They also comes with the features like adjustable airflow direction, multiple fan speeds. The cost of a floor-mounted air conditioner can vary depending on factors such as size, features and other parameters.

Smart Air Conditioner

Smart Air Conditioner is a type of cooling systems that uses advance technology to have better convenience, control, and energy efficiency. These Ac units can be controlled using smartphones or using internet connected devices. Smart AC units also have features like scheduling that allow users to program cooling schedules based on their daily routines. It include diagnostic capabilities that can detect issues with the system and send alerts to the user’s smartphone.

Evaporator Cooler

Evaporator Cooler are also known as swamp cooler is a type of cooling systems that uses evaporation of water for cooling. It work on the principle of evaporative cooling where hot and dry air passes through water-saturated pads. As the air absorbs moisture from the pads it undergoes a cooling effect which reduces its temperature. Evaporative coolers are mostly installed on the roof or outside walls of buildings with ducts or vents distributing the cooled air indoors. Some portable models are designed for indoor use and can be placed in a window outside.

Conclusion

The vast range of air conditioning systems available today indicates ongoing innovation and adaptation in response to changing demands and environmental concerns. From ancient window units to advanced split systems and advanced central air conditioning, each kind serves a specific purpose and caters to different areas and demands. Portable air conditioners are flexible and mobile, making them ideal for smaller rooms or temporary cooling requirements. Window units, on the other hand, are a low-cost choice for specific rooms, while split systems offer more complete options for bigger spaces. Central air conditioning, with its capacity to efficiently cool large buildings, is still widely used in both commercial and residential settings.

Furthermore, the introduction of smart technology has brought a new phase of energy efficiency and user control, allowing people to regulate their climatic preferences more precisely. As the need for sustainable solutions increases, eco-friendly refrigerants and energy-efficient designs highlight the industry’s commitment to environmental stewardship.

Types of Air Conditioning – FAQs

Which is the new AC technology ?

The most recent air conditioning technology employs renewable energy sources such as solar energy. This sort of HVAC technology is not restricted to solar energy and natural gas but also includes thermally powered heating and cooling. The most recent HVAC technology employs natural gas in order to cool buildings, lowering power expenses.

What are the thermodynamics behind the refrigeration cycle in air conditioning systems?

The refrigeration cycle in air conditioning systems have four key steps: compression, condensation, expansion, and evaporation. First, the compressor pressurizes the refrigerant, heating it up. Then, the hot gas releases heat outside, turning into a liquid. Next, the liquid expands and cools as it passes through a valve. Finally, the cooled liquid absorbs heat indoors, turning back into a gas and repeating the cycle. This process continuously removes heat from inside, keeping the indoor environment cool.

How can we determine the energy efficiency of an air conditioning system?

The energy efficiency of an air conditioning system can be determined by its Energy Efficiency Ratio (EER), which measures cooling capacity relative to power input. Higher EER ratings indicate greater efficiency.