WO2022130400A1

WO2022130400A1 - A system for developing germicidal properties in ac units by externally installing an ultraviolet source device

Info

Publication number: WO2022130400A1
Application number: PCT/IN2021/051162
Authority: WO
Inventors: Vaibhav Verma
Original assignee: Vaibhav Verma
Priority date: 2020-12-20
Filing date: 2021-12-10
Publication date: 2022-06-23

Abstract

The present invention portrays to a system of ultraviolet electromagnetic radiation in disinfection of air flowing through air conditioning and air cooling systems (AC unit). Herein, a UV source device is arranged externally with the AC unit such that the air flowing though the AC unit is exposed to ultraviolet range of electromagnetic radiation emitted by the device and the UV light eliminates the microorganisms and pathogens present in the airstream by damaging their DNA/RNA and also eliminating odour from the airstream. Also, an enclosure/cover is installed in order to prevent the escape/leakage of the UV light in the surroundings. This invention also provides methods to further enhance the efficiency of the system with the use of photocatalyst and/or by installation of a moisture amplification device and/or by installation of reflective materials in the unit and also provides methods to control the switch on/off state of the UV source device. Hence, providing the facility of eliminating bacteria, virus, fungus, etc. present in air, hence disinfecting the air stream flowing through the AC unit.

Description

A SYSTEM FOR DEVELOPING GERMICIDAL PROPERTIES IN AC UNITS BY EXTERNALLY INSTALLING AN ULTRAVIOLET SOURCE DEVICE”

Field of Invention:

The present invention portrays to application of ultraviolet electromagnetic radiation in disinfection of air flowing through air conditioner and air cooler systems (AC unit) by externally installing a UV source device. Hence providing the facility of eliminating bacteria, virus, fungus, etc. present in air, when the air flows through AC unit hence disinfecting the air stream.

Background:

Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

Air is essential for all living organisms to stay alive and function. However, air is also a very common medium for microorganisms (pathogens) such as bacteria, virus, etc. to communicate. Air can lead to transmission of pathogens and contamination of whole rooms, houses or even buildings. In recent times, with the rise of virus like COVID-19, it is has been observed that if one infected person is present in a room or a vehicle with other people, then the other people have a very high risk of getting infected through the air circulated in the environment. Many other pathogens, including but not limited to bacteria, virus, fungus, parasite, prion, etc. have the ability to transmit/spread in the same way through air. Such pathogens enter the body while breathing and lead to various diseases.

In order to reduce chances of contact from such pathogens, humans can regularly wash hands and wear face masks but these methods cannot be effectively preformed 24 hours daily. Since wearing masks for a long time creates various problems and the same cannot be performed while in home or while sleeping. Disinfection of air from such pathogens currently is a very i tedious and costly process and is currently unavailable for the society. Hence, a method of disinfecting the air is urgently required in order to efficiently and economically reduce the risks of such pathogens and help in controlling pandemics.

Humans have always had the capacity and desire to change their habitats to increase their comfort and convenience. One of such requirements has been to alter the temperature of their environments and this has been achieved through the invention of air conditioning and cooling systems (collectively referred to as “AC unit(s)” or “AC system(s)” in this disclosure) that basically convert the nature of the air stream flowing through them as per requirement. AC units are used in both large commercial areas/buildings and domestic environments. However, after the commercialization of the same, the cost and size of AC units has reduced and their efficiency has increased. Hence, they have now become a very common appliance to be installed in houses. Also, such units are now very common and have also become necessary to be installed in mobile machinery such as airplanes, ships, trains, buses, cars, automobiles, etc.

Along with amendment in the temperature of the air, various methods have also been used for filtration and purification of the air stream flowing through AC units. Methods have been used to filter dust particles, particulates through air using sieve like filters with different properties. Such methods can be applied to a certain extent to reduce the pathogens in the air but this method certainly cannot kill them completely, therefore still leaving chances of infection. Hence, a completely effective and economic method for such decontamination is still not available for the society.

Previously UV light has been used for disinfection of water, materials, goods, fruits/vegetables, clothes, etc. in such applications, the desired product is exposed to UV light and it kills the pathogens present on the exposed surface of the product, hence, disinfecting the exposed surface.

Also, some methods were invented for use of UV lights for HVAC units but they were only intended for large/industrial HVAC systems for disinfection of mechanical components like cooling coils, duct components, etc. and hence couldn’t fulfil the domestic needs of the same. Also they were either costly, inefficient, had an awkward fitting mechanism and also were not available for small/household AC units. Such methods lacked the ability to convert already installed/active domestic AC units.

Currently, general air purifiers also cannot ensure the complete elimination of pathogens from the air and such air purifiers need additional power source for circulating the air through them and they also need periodic replacements of various parts. Therefore, increasing maintenance costs and proving to be less efficient.

Therefore the present disclosure overcomes the above mentioned problems associated with the traditionally available method or system.

All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.

As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.

All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.

Objective:

The present invention discloses an air decontamination technique that can easily convert already installed/active and/or new/under manufacturing AC units and generate the potential in them for killing pathogens by externally installing a UV source device. The disclosed technique can easily be employed in already installed/active and/or new/under manufacturing AC systems such as air conditioners, air coolers, etc. in home, vehicles, room, buildings, etc.

The principal objective of this invention is to provide a system for disinfection of air flowing through AC systems, from microorganisms and pathogens by exposing the air to ultraviolet electromagnetic radiation emitted by a UV source device installed externally near the unit.

Another objective of this invention is to provide an economic, easy and efficient system to convert existing/already installed/active AC units and add germicidal features in the same.

Another objective of this invention is to reduce the odour in air by exposing such particles present in the air stream to UV light and also automatically protecting the exposed parts of AC from mold formation.

Another objective of this invention is to increase the efficiency of the invention by use of photocatalyst and/or installation of reflective materials in the AC unit.

Another objective of this invention is to provide means of cover/enclosure for the UV source device to prevent unnecessary leakage of UV light in the environment.

Another objective of this invention is to increase the efficiency of the system by installing a moisture amplification device to drastically increase the production of free radicals. Another objective of this invention is to provide different methods to control the switching on/off of the UV source device.

Summary:

The present invention provides a method to disinfect air stream flowing through AC systems with the use of ultraviolet electromagnetic radiation, in which, the air flowing through the unit is exposed to ultraviolet (UV) electromagnetic radiation, emitted by the UV source device installed externally near the AC unit and the pathogens in the air are exterminated due to the effect of UV light.

Ultraviolet range (between 100-400nm specially Ultraviolet-C between 200- 280nm) of electromagnetic radiation has germicidal properties which help in disinfection of surfaces and mediums including air and fluids. UV at these germicidal wavelengths damage a microorganism's DNA/RNA so that it cannot reproduce, hence, making it harmless.

The main effect of ultraviolet electromagnetic radiation on biological systems works by two methods, (i) it produces a large number of free radicals that destabilise macromolecules and (ii) it is absorbed by the DNA molecules in the cells of microorganisms and cause alterations that damage the microorganism.

It is a well-known fact that short wavelength rays (such as UV) interact with water molecules in the cell to produce free radicals (-OH). Such free radicals lack an electron and attack other molecules such as cell proteins or DNA to absorb their electron. Many free radicals may retrieve electrons from the same large cell molecule and cause changes in the molecule in a way that makes its role useless.

The most common change in the DNA molecule brought about by UV irradiation and consequently by the free radicals occur at locations on the molecule where two thymine (one of the bases that make up DNA) bases occur adjacent to each other. UV irradiation causes the two thymine bases to fuse to each other on the same strand. Such structures are called thymine dimers and cause a distortion in the shape of DNA. Thus, when next time it goes for DNA replication, a wrong base may be incorporated at the thymine dimer position on the strand being synthesised. This would constitute a site of mutation and when it involves a protein that plays a role in cell survival, it will be lethal. Hence exposing the air to ultraviolet electromagnetic radiation will disinfect the air stream from any microorganisms/pathogens present in the same.

Additional cover/enclosure of transparent/translucent/opaque/reflective materials can also be installed with the UV source device to prevent escape/leakage of UV light in nearby surroundings, which would unnecessarily expose unwanted objects in the environment with the UV radiation. Such cover can be fixed with the UV light device and/or on the mount and/or on the AC unit as designed and the angle/design can be fixed or can also be designed to be adjusted as per the requirements of the user.

Apart from the main motive of disinfection of air, this method has additional benefits like reduction of odour from air due to exposure to UV radiation. Since, UV light interacts with water molecules in the air to produce free radicals (O- and -OH), these free radicals go on to oxidise the complex molecules found in the air and as an outcome, the end result is a sequential and instantaneous gas breakdown, which eliminates the odour causing molecules form air. Hence, this method is also effective in increasing the ambience of the surrounding. Also, UV radiation protects the exposed AC parts from mold formation by eliminating the mold forming microorganisms.

Brief Description of drawings:

The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

Figure 1 illustrates an architecture of a split type air conditioner. Figure 2 visualises a demarcation of air intake area of split type air conditioners.

Figure 3 illustrates a layout in which split air conditioners are installed.

Figure 4 illustrates a few UV source device designs.

Figure 5 displays an exemplary position for placing the UV source device above the AC unit.

Figure 6 illustrates a UV source device placed on the position depicted in Figure 5.

Figure 7 visualises a demarcation of the area that should be exposed to UV radiation.

Figure 8 illustrates a few exemplary designs of cover/enclosure for the UV source device.

Figure 9 illustrates a visualisation of the working of cover/enclosure.

Figure 10 illustrates a moisture amplification device.

Figure 1 1 illustrates an exemplary illustration of moisture amplification device placed near the AC Unit.

Detailed Description:

In the following description, numerous specific details are set forth in order to provide a thorough understanding of embodiments of the present invention. It will be apparent to one skilled in the art that embodiments of the present invention may be practiced without some of these specific details.

The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.

AC units work on the basis of refrigeration cycle, sometimes on evaporation or free cooling basis also. In all such systems, the air stream flowing through the unit is converted as per the desire of the user. Hence, the present invention does not need any additional power/mechanism for inducing air circulation, since air is already flowing through the AC unit and the UV source device is placed such that the flowing air is exposed to the ultraviolet electromagnetic radiation emitted by the UV source device.

Figure 1 illustrates the architecture of indoor unit (1 ) of a split type air conditioner mounted on a wall (7). Consisting of an air inlet (2) providing air input (8), front panel (3), air filter (4), horizontal blades (5) providing air output (9) and a connecting pipe (6).

Figure 2 illustrates the top portion of the indoor unit (1 ), visualising the air inlet (2) and demarcates the desired exposure area (10).

Figure 3 illustrates the installation layout of such AC units, visualising the indoor unit (1 ), front panel (3), air filter (4), horizontal blades (5), connecting pipe (6), air input (8), air output (9), unit case (11 ), wiring cover (12), function switch (13), drain pipe (14), outdoor unit mount (15), outdoor air input (17), outdoor air output (18) and outdoor unit (16).

Split AC units are basically divided into two parts, indoor unit (1 ) and outdoor unit (16). The Indoor unit (1 ) is mounted on the wall (7) of the room and is connected to the outdoor unit (16) with the help of a connecting pipe (6). The indoor unit basically consists of an air inlet (2), air filter (4) enclosed in a panel (3) on front along with the wiring enclosed within the wiring cover (12) and a function switch (13) forming the control panel, all installed on the unit case (1 1 ), arranged such that air enters (8) the indoor unit (1 ) through the air inlet (2) then passes through the air filter (4) enclosed in the indoor unit (1 ) behind the front panel (3). The air is then processed by the indoor unit (1 ) and exits the indoor unit (1 ) from the horizontal blades (5) which also controls the direction of the flow of air and provides air output (9). The condensed water from the indoor unit (1 ) is released through the drain pipe (14). The outdoor unit (16) is fixed through the mounts (15) and is connected to the indoor unit (1 ) through a connecting pipe (6) and the outdoor unit (16) has outdoor air intake (17) and outdoor air output (18) circulation to exchange heat from the condenser coil.

Figure 4 illustrates a few UV source devices with visualisation from different angels, such as quartz lamp (20) with a conventional method of installation of the baten (21 ) on the holder and the power for the same is supplied through electric wires (19). Similarly, LED based devices (22) and LED strip (23) which work on the basis of light emiting diodes (24) are also meant to be used in a similar manner as disclosed. These UV source devices are meant to release light of the ultraviolet range (between 100-400nm specially UV-C between 200-280nm). The power of the device (measured in W{watt}) can vary as per the needs of the user.

Various devices are available that can generate ultraviolet range of electromagnetic radiation, such as LED, Quartz, Low pressure mercury lamp, Excimer Lamp, Pulsed Xenon Lamp, etc. and all such devices even if invented in future can be easily used in a similar manner as disclosed in this present disclosure and is/are within the scope of this disclosure.

When the air is exposed to electromagnetic radiation of ultraviolet range, the microorganisms/pathogens in the same are eliminated by the following procedure :

Short wavelength rays (such as UV) interact with water molecules in the cell to produce free radicals (-OH). Such free radicals lack an electron and attack other molecules such as cell proteins or DNA to absorb their electron. Many free radicals may retrieve electrons from the same large cell molecule and cause changes in the molecule hence making the microorganism disabled.

The most common change in the DNA molecule brought about by UV irradiation and consequently by the free radicals occur at locations on the molecule where two thymine (one of the bases that make up DNA) bases occur adjacent to each other. UV irradiation causes the two thymine bases to fuse to each other on the same strand. Such structures are called thymine dimers and cause a distortion in the shape of DNA. Thus, when next time it goes for DNA replication, a wrong base may be incorporated at the thymine dimer position on the strand being synthesised. This would constitute a site of mutation and when it involves a protein that plays a role in cell survival, it will be lethal. Hence exposing the air to ultraviolet electromagnetic radiation disinfects the air stream from any microorganisms/pathogens present in the same.

Apart from the main motive of disinfection of air, this method has additional benefits like reduction of odour from air due to exposure to UV radiation. Since, UV light interacts with water molecules in the air to produce free radicals (O- and -OH), these free radicals go on to oxidise the complex molecules found in the air and as an outcome, the end result is a sequential and instantaneous gas breakdown, which eliminates the air from odour causing molecules. Hence, this method is also effective in increasing the ambience of the surrounding. Also, UV light protects the exposed AC parts from mold formation by eliminating the mold forming microorganisms.

Figure 5 illustrates a position for placing the UV source device, visualising the position (25) demarcated through dashed lines for UV source device (29) of length (28) and height (27) of the UV source device and the height (26) of position (25) above the indoor unit (1 ).

Figure 6 visualises a UV source device (29) placed on the position demarcated in Figure 5. io In a split AC, the air flows through the indoor unit (1 ) chronologically through air inlet (2), air filters (4), evaporator coil, blower and then air outlet (5). The UV source device is placed externally near the indoor unit (1 ) such that the air entering the unit is exposed to the UV radiation. Hence, an exemplary placement has been visualised in Figure 6 such as, a device (29) is placed above the AC unit (1 ) so that the air flowing through the air inlet is exposed to UV light. In this visualisation, the sole purpose of the placement of the UV source device is to expose the flowing airstream to UV radiation.

Figure 7 demarcates the effectively desired area (10) demarcated by dashed lines (10) and the length of area (30) for exposure to UV radiation.

Figure 8 illustrates a few designs of cover/enclosure, such as an inclined model (31 ) which can basically be divided into three parts, namely wall portion (32) of width (38), top portion (33) of width (39) and inclined portion (34) of width (40), inclined at an angle (36) at point (35) depending on the required exposure angle (46) and with the total cover length (37).

Figure 8 illustrates another design (41 ) which has a curved model which can basically be divided into two parts, namely wall portion (42) of width (44) and curved portion (43) with the total cover length (45).

Figure 9 illustrates a visualisation of the working of such cover (47).

In order to prevent the leakage of UV light to the surrounding, an enclosure/cover (47) can be designed and installed above the UV source device (29) such that the cover (47) either absorbs and/or dilutes and/or reflects the UV light which is inbound to the cover (47). Hence, preventing the light from escaping to the surroundings. This will help to eliminate the risk of unnecessary exposure to people and objects in the vicinity of the system. The cover can be shaped in various designs and can be made of various transparent/translucent/opaque/reflective materials (solid or bendable) with the sole purpose to prevent the escape of UV light from the desired exposure area and increase the efficiency of the system. In all the above mentioned units, the air already flows through the unit and hence no special change/amendment is required to be done on the unit for this disclosure to work. The main motive of this disclosure is to place a UV source device externally near the AC unit such that the air flowing through the AC unit is exposed to UV radiation. Hence, the airstream will be disinfected from pathogens with the effect of UV light.

Additionally, photocatalyst materials such as titanium dioxide, strontium titanate, etc. can also be installed along with the UV source device in the system in order to enhance the performance of the device by initiating the process of photocatalysis, which excites the UV light rays inbound on the photocatalyst material, which consequently increases the amount of free radicals and hence increases the efficiency of the system.

Figure 10 illustrates a moisture amplification device (1 a) consisting of an ultrasonic transducer (3a), water (2a), air inlet (4a), fan (6a), power supply (8a), water inlet (9a), water storage area (10a), and moisturised air outlet (1 1 a).

The moisture amplification device (1 a) has been designed to produce intensely moisturized air. The water (2a) from the water storage area (10a) is converted into minute (water) particles (5a) by the ultrasonic transducer (3a) which oscillates at ultrasonic frequency (greater than 20,000 hertz) and hence this forms an extremely fine mist of water which quickly evaporates with air flow, hence producing intensely moisturized air (7a) to feed into the system. Further, this intensely moisturized air (7a) is circulated with the help of a fan (6a) and is mixed with air coming from air inlet (4a) which leads to an output of intensely moisturized air (7a) via a moisturized air outlet (1 1 a). The water inlet (9a) provides consistent input of water (2a) into the device. Figure 1 1 visualises a moisture amplification device (1 a) installed to provide intensely moisturised air (7a) into the AC unit (1 ). The moisture amplification device (1 a) is installed near the AC unit (1 ) such that it provides an output of intensely moisturized air (7a). The moisture amplification device is arranged externally with the AC unit to increase moisture content in the air flowing through the AC unit i.e., to increase moisture content in airstream entering the AC unit.

This intensely moisturised air (7a) from the moisture amplification device (1 a) is then further circulated with the air stream of the system and when exposed to UV radiation, the water molecules present in the airstream are broken down by the effect of UV radiation to produce hydrogen and hydroxide ions.

These free radicals are highly unstable and react with pathogens and render them inactive. This device can be used additionally to increase the efficiency of the system. Similar methods to increase moisture in air can be applied such as evaporation based amplification device which shall pass air through a wet membrane to increase moisture content and consequently increase the efficiency. Further, when used in air conditioning systems, the water input can also be provided by the condensed water which is usually drained out.

In brief, the moisture amplification device (1 a) consisting of the water inlet (9a) and the ultrasonic transducer (3a) to create an output of intensely moisturized air configured to provide the intensely moisturized air into the AC unit (1 ). UV Light

The moisture amplification device (1 a) consists of the ultrasonic transducer (3a) to form an extremely fine mist of water to increase moisture content in air.

The moisture amplification device (1 a) consists of a porous membrane or wick instead of the ultrasonic transducer (3a) to evaporate water into the airstream.

The moisture amplification device (1 a) consists of the fan (6a) to induce air circulation to allow mixing of the air and the fine mist of water. The moisture amplification device (1 a) consists of the water storage area (10a).

The moisture amplification device (1 a) consists of the water inlet (9a) to provide water input.

The moisture amplification device (1 a) consists of the air inlet (4a) to provide air input.

Additionally, the surfaces of AC unit and/or cover which are exposed to UV light can be covered/coated with reflective materials such that the UV light inbound to such surfaces is reflected, which would increase the intensity of the UV light within the system and hence increase the efficiency of the system.

The UV source device can directly be connected to the respective power source and be switched on/off manually/automatically or it can also simply be connected along with the AC unit control panel/power source such that it switches on and off along with the AC unit. To further improve the facility of users, the UV source device can also be directly connected in the control panel of the system and the remote control of the unit may be incorporated with a control button to switch on/off the device.

Also, flow activated sensor for activation of the UV source device on airflow, etc. can also be installed in the path of airstream and can be connected to the UV source device to control the power supply to UV source device. Such systems are optional and can be installed additionally apart from the UV source device in order to increase the convenience for the use of the same.

In an embodiment of the present disclosure, a method of disinfecting air flowing through AC unit comprises the steps of : exposure of air to UV light by installing the UV source device externally near the unit such that the airstream is irradiated with UV light while flowing through the AC unit. The air then gets disinfected from microorganisms/pathogens by the effect of UV light. If the specification states a component or feature “may”, “can”, “could”, or “might” be included or have a characteristic, that particular component or feature is not compulsorily required to be included or have the characteristic.

Exemplary embodiments have been described more fully herein with reference to the accompanying drawings, in which exemplary embodiments are shown. This invention may, however, be embodied in many different forms and should not be limited to the embodiments set forth herein. These embodiments have been provided in order to make this disclosure thorough and complete in order to fully convey the scope of the invention to those of ordinary skill in the art. Moreover, all statements herein reciting embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future (i.e., any elements developed that perform the same function, regardless of structure/size).

Each of the appended claims defines a separate invention, which for infringement purposes is recognised as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognised that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.

Various terms as used herein are shown below. To the extent a term used in a claim is not defined, it should be given the broadest definition that persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.

While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

Claims

The Claims:

1. A system for disinfecting air comprising: an air conditioner and cooling (AC) unit; and at least one ultraviolet (UV) source device arranged externally with the AC unit to irradiate air flowing through the AC unit with UV light.

2. The system for disinfecting air as claimed in claim 1 , wherein the at least one UV source device comprises Light-Emitting Diode (LED), Quartz lamp, low pressure mercury lamp, Excimer lamp, and Pulsed Xenon lamp.

3. The system for disinfecting air as claimed in claim 1 , wherein the at least one UV source device generates an electromagnetic radiation with wavelength between 100 and 400nm.

4. The system for disinfecting air as claimed in claim 1 , wherein the AC unit is one of an air conditioner, and an air cooler.

5. The system for disinfecting air as claimed in claim 1 , comprises of a cover installed with the at least one UV source device to prevent leakage of UV light to surroundings.

6. The system for disinfecting air as claimed in claim 5, wherein the cover is made of a transparent material or a translucent material or an opaque material or a reflective material or combination thereof.

7. The system for disinfecting air as claimed in claim 1 , wherein a photocatalyst material is arranged along with the at least one UV source device to initiate a process of photocatalysis for exciting the UV light inbound on the photocatalyst materials.

8. The system for disinfecting air as claimed in claim 1 , wherein the portions of the AC unit and/or cover exposed to the UV light are coated with reflective material to reflect the UV light. The system for disinfecting air as claimed in claim 1 , further comprising a moisture amplification device arranged externally with the AC unit to increase moisture content in the air flowing through the AC unit. The system for disinfecting air as claimed in claim 1 , wherein the at least one UV source device disinfects the air and removes odour from the air flowing through the AC unit by breaking down the odour causing molecules. The system for disinfecting air as claimed in claim 1 , wherein the at least one UV source device disinfects the air and protects the exposed parts of the AC unit from mold formation by eliminating the mold forming microorganisms. The system for disinfecting air as claimed in claim 1 , wherein the at least one UV source device is powered by a separate power source or by a power source of the AC unit. The system for disinfecting air as claimed in claim 1 , wherein the at least one UV source device is connected with a control panel of the AC unit; and wherein the at least one UV source device is controlled using remote control of the AC unit. The system for disinfecting air as claimed in claim 1 wherein, the at least one UV source device is connected with a flow activated sensor programmed to control on/off state of the at least one UV source device as per airflow speed in the AC unit.