Patent Description:
A transport climate control system can include, for example, a heating, ventilation and air conditioning (HVAC) system and/or a transport refrigeration system (TRS). An HVAC system is generally used to control a climate within a passenger space of a vehicle (e.g., a passenger bus, a cabin of a tractor, etc.). A TRS is generally used to control an environmental condition (e.g., temperature, humidity, air quality, and the like) within a cargo space of a transport unit (e.g., a truck, a container (such as a container on a flat car, an intermodal container, etc.), a box car, a semi-tractor, a bus, or other similar transport unit). The TRS can maintain environmental condition(s) of the cargo space to maintain cargo (e.g., produce, frozen foods, pharmaceuticals, etc.).

Society's vulnerabilities to a rapidly spreading virus were exposed during the COVID-<NUM> pandemic. Transit vehicles typically service many riders in a day and have people regularly entering or leaving the vehicle. The passengers can be in close proximity, within an enclosed space in the transit vehicle. These conditions can facilitate the spread of communicable diseases and pathogens such as COVID-<NUM>. In particular, in a mobile society in which transportation is essential to commerce, e.g., the transport of good as well as the transport of people to jobs, schools, etc., legitimate hygienic solutions that foster confidence in various forms of transport are a benefit public health and safety.

<CIT> discloses an air conditioning device including an air purifier, a sensor, a communicator, and a processor. The sensor is configured to measure an air pollution level. The processor is configured to activate the sensor in a state where the air purifier is not driven, in response to receiving a signal requesting an air pollution level state information from a server based on a location of a mobile terminal, transmit a second signal indicating that the air conditioning device needs to be driven to the server based on the air pollution level measured by the sensor, and drive the air purifier in response to a driving instruction from the server. <CIT> discloses a climate control system of a vehicle and a method of controlling the climate control system, the climate control system including a main HVAC system for conditioning a fluid discharged into a passenger compartment of the vehicle, an auxiliary HVAC system for conditioning a localized fluid of at least one HVAC zones of the passenger compartment, a seat system, and an HVAC controller.

This disclosure is directed to methods and systems for sanitizing air conditioned by a climate control system. The invention is defined in the attached independent claims, to which reference should now be made. Further, optional features are defined in the sub-claims appended thereto.

The embodiments described herein can provide an effective air sanitization solution for use in climate control applications where there may be high air exchange rates. Accordingly, volatile organic compounds including, for example, viruses, pathogens, and bacteria can be effectively reduced in high air exchange rate climate control applications.

The embodiments described herein can also track an effectiveness of an air sanitization system used in a climate control application. Accordingly, a user can determine when a component of the air sanitization system (e.g., an air sanitizer) has lost sufficient efficacy and may need maintenance (e.g., repair or replacement).

It will be appreciated that the invention as claimed refers to a vehicle having or towing a space within which air is to be purified.

In an embodiment according to the invention as claimed, a method for purifying air within a climate controlled space according to claim <NUM> is provided. The method includes a controller determining whether an ON signal is received, the signal indicating that a vehicle having or towing the space is turned ON. Upon determining that the ON signal is received, the controller instructs an air sanitizer of an air sanitization system to turn ON to purify an airflow passing through the air sanitization system, and instructs an air movement fan/blower of a climate control system to operate in order to direct the airflow into the climate controlled space. Upon determining that the ON signal is not received, the controller instructs the air movement fan/blower and the air sanitizer to be OFF.

In another embodiment of the invention as claimed, a system for purifying air within a climate controlled space according to claim <NUM> is provided. The system includes an air sanitization system, a climate control system, and a controller. The air sanitization system includes an air sanitizer configured to purify an airflow passing through the air sanitization system. The climate control system includes an air movement fan/blower configured to direct the airflow into the climate controlled space. The controller is configured to determine whether an ON signal is received, the signal indicating that a vehicle having or towing the space is turned ON. Upon determining that the ON signal is received, the controller is configured to instruct the air sanitizer to turn ON for a set time period to purify the airflow passing through the air sanitization system, and instruct the air movement fan/blower to operate in order to direct the airflow into the climate controlled space. Upon determining that the ON signal is not received, the controller is configured to instruct the air movement fan/blower and the air sanitizer to be OFF.

References are made to the accompanying drawings that form a part of this disclosure, and which illustrate embodiments in which the systems and methods described in this Specification can be practiced.

This invention is directed to methods and systems for sanitizing air conditioned by a climate control system.

A transport climate control system is generally used to control one or more environmental conditions such as, but not limited to, temperature, humidity, air quality, or combinations thereof, of a transport unit. Examples of transport units include, but are not limited to a truck, a container (such as a container on a flat car, an intermodal container, a marine container, a rail container, etc.), a box car, a semi-tractor, a mass-transit vehicle (such as a passenger bus, a passenger train, etc.), or other similar transport unit. A climate controlled transport unit can be used to transport perishable items such as pharmaceuticals, produce, frozen foods, and meat products and/or can be used to provide climate comfort for passengers in a passenger space of a mass-transit vehicle. The transport climate control system may include a vapor-compressor type climate controlled system, a thermal accumulator type system, or any other suitable climate controlled system that can use a working fluid (e.g., refrigerant, etc.), cold plate technology, or the like.

A transport climate control system can include a climate control unit (CCU) attached to a transport unit to control one or more environmental conditions (e.g., temperature, humidity, air quality, etc.) of a climate controlled space of the climate controlled transport unit. The CCU can include, without limitation, a climate control circuit (including, for example, a compressor configured to compress a working fluid (e.g., refrigerant), a condenser, an expansion valve, and an evaporator), and one or more fans or blowers to control the heat exchange between the air within the climate controlled space and the ambient air outside of the climate controlled transport unit.

<FIG>, <FIG> and <FIG> show various transport climate control systems. It will be appreciated that the embodiments described herein are not limited to the examples provided below, but can apply to any type of transport unit (e.g., a truck, a container (such as a container on a flat car, an intermodal container, a marine container, etc.), a box car, a semi-tractor, a passenger bus, or other similar transport unit), etc..

<FIG> is a perspective view of a mass-transit vehicle <NUM> including a climate control system, according to one embodiment. In the embodiment illustrated in <FIG>, the vehicle <NUM> is a mass-transit bus that can carry passenger(s) (not shown) to one or more destinations. In other embodiments, the vehicle <NUM> can be a school bus, railway vehicle, subway car, or other commercial vehicle that carries passengers. Hereinafter, the term "mass-transit vehicle" shall be used to represent all such vehicles, and should not be construed to limit the scope of the application solely to mass-transit buses.

<FIG> shows that the vehicle <NUM> includes a frame <NUM>, a passenger compartment <NUM> supported by the frame <NUM>, wheels <NUM>, and a compartment <NUM>. The frame <NUM> includes doors <NUM> that are positioned on a side of the vehicle <NUM>. As shown in <FIG>, a first door <NUM> is located adjacent to a forward end of the vehicle <NUM>, and a second door <NUM> is positioned on the frame <NUM> toward a rearward end of the vehicle <NUM>. Each door <NUM> is movable between an open position and a closed position to selectively allow access to the passenger compartment <NUM>.

The vehicle <NUM> also includes a climate control unit <NUM> attached to the frame <NUM> on a roof <NUM> of the vehicle <NUM>. The climate control unit <NUM> is part of a transport climate control system (not shown) that is configured to provide climate control within the passenger compartment <NUM>. In some embodiments, the climate control unit <NUM> can include a climate control circuit (not shown) with one or more fans/blowers to provide climate conditioned air within the passenger compartment <NUM>. The climate control unit <NUM> can be combined with an air sanitization system (see <FIG>) that is configured to purify air within the passenger compartment <NUM>. While the climate control unit <NUM> is shown as a rooftop mount onto the roof <NUM>, it will be appreciated that in other embodiments the climate control unit <NUM> can be located at other sides of the vehicle <NUM> (e.g., mounted to a rear end of the vehicle <NUM>).

The compartment <NUM> is located adjacent the rear end of the vehicle <NUM>, can include a power system (not shown) that is coupled to the frame <NUM> to drive the wheels <NUM>. In some embodiments, the compartment <NUM> can be located in other locations on the vehicle <NUM> (e.g., adjacent the forward end, etc.).

<FIG> illustrates a vehicle <NUM> according to one embodiment. The vehicle <NUM> is a semi-tractor that is used to transport cargo stored in a cargo compartment (e.g., a container, a trailer, etc.) to one or more destinations. Hereinafter, the term "vehicle" shall be used to represent all such tractors and trucks, and shall not be construed to limit the invention's application solely to a tractor in a tractor-trailer combination. In some embodiments, the vehicle <NUM> can be, for example, a straight truck, van, etc..

The vehicle <NUM> includes a primary power source <NUM>, a cabin <NUM> defining a sleeping portion <NUM> and a driving portion <NUM>, an APU <NUM>, and a plurality of vehicle accessory components <NUM> (e.g., electronic communication devices, cabin lights, a primary and/or secondary HVAC system, primary and/or secondary HVAC fan(s), sunshade(s) for a window/windshield of the vehicle <NUM>, cabin accessories, etc.). The cabin <NUM> can be accessible via a driver side door (not shown) and a passenger side door <NUM>. The cabin <NUM> can include a primary HVAC system (not shown) that can be configured to provide conditioned air within driving portion <NUM> and potentially the entire cabin <NUM>, and a secondary HVAC system (not shown) for providing conditioned air within the sleeping portion <NUM> of the cabin <NUM>. In some embodiments, the secondary HVAC system can be combined with an air sanitization system (see <FIG>) that is configured to purify air within the sleeping portion <NUM> of the cabin <NUM>. The cabin <NUM> can also include a plurality of cabin accessories (not shown). Examples of cabin accessories can include, for example, a refrigerator, a television, a video game console, a microwave, device charging station(s), a continuous positive airway pressure (CPAP) machine, a coffee maker, a secondary HVAC system for providing conditioned air to the sleeping portion <NUM>.

The primary power source <NUM> can provide sufficient power to operate (e.g., drive) the vehicle <NUM> and any of the plurality of vehicle accessory components <NUM> and cabin accessory components <NUM>. The primary power source <NUM> can also provide power to the primary HVAC system and the secondary HVAC system. In some embodiments, the primary power source can be a prime mover such as, for example, a combustion engine (e.g., a diesel engine, etc.).

The APU <NUM> is a secondary power unit for the vehicle <NUM> when the primary power source <NUM> is unavailable. When, for example, the primary power source <NUM> is unavailable, the APU <NUM> can be configured to provide power to one or more of the vehicle accessory components, the cabin accessories, the primary HVAC system and the secondary HVAC system. In some embodiments, the APU <NUM> can be an electric powered APU. In other embodiments, the APU <NUM> can be a prime mover powered APU. The APU <NUM> can be attached to the vehicle <NUM> using any attachment method. In some embodiments, the APU <NUM> can be turned on (i.e., activated) or off (i.e., deactivated) by an occupant (e.g., driver or passenger) of the vehicle <NUM>. The APU <NUM> generally does not provide sufficient power for operating (e.g., driving) the vehicle <NUM>. The APU <NUM> can be controlled by an APU controller <NUM>.

<FIG> illustrates an electric APU <NUM> that can be used with a vehicle (e.g., the vehicle <NUM> shown in <FIG>), according to one embodiment. The APU <NUM> includes a plurality of energy storage elements <NUM> each of which is coupled to one of a plurality of converters <NUM>. The converters <NUM> can provide electric power (e.g., AC or DC power) generated by the APU <NUM> to one or more vehicle accessory components, cabin accessory components, a primary HVAC system, and a secondary HVAC system. A secondary HVAC system can provide conditioned air to a sleeping portion of a vehicle cabin (e.g., the sleeping portion <NUM> of the cabin <NUM> shown in <FIG>). The energy storage elements <NUM> can be, for example, battery packs, fuel cells, etc. In some embodiments, the APU <NUM> can be turned on or off by an occupant (e.g., driver or passenger) of the vehicle. For example, the occupant can turn on the APU <NUM> to provide power stored in the energy storage elements <NUM> when a primary power source of the vehicle is turned off. It will be appreciated that the embodiments described herein can also be used with a prime mover powered APU.

In some embodiments, the APU (e.g., the APU <NUM> as shown in <FIG> and/or the APU <NUM> as shown in <FIG>) includes a vehicle electrical system.

<FIG> illustrates one embodiment of a climate controlled transport unit <NUM> attached to a tractor <NUM>. The climate controlled transport unit <NUM> includes a climate control system <NUM> for a transport unit <NUM>. The tractor <NUM> is attached to and is configured to tow the transport unit <NUM>. The transport unit <NUM> shown in <FIG> is a trailer. It will be appreciated that the embodiments described herein are not limited to tractor and trailer units, but can apply to any type of transport unit (e.g., a container on a flat car, an intermodal container, etc.), a truck, a box car, or other similar transport unit. The transport unit <NUM> can include one or more doors (not shown) that are movable between an open position and a closed position to selectively allow access to a climate controlled space <NUM>.

The climate control system <NUM> includes a climate control unit (CCU) <NUM> that provides environmental control (e.g. temperature, humidity, air quality, etc.) within the climate controlled space <NUM> of the transport unit <NUM>. The climate control system <NUM> also includes a climate controller <NUM> and one or more sensors (not shown) that are configured to measure one or more parameters of the climate control system <NUM> and communicate parameter data to a climate controller <NUM>.

The CCU <NUM> is disposed on a front wall <NUM> of the transport unit <NUM>. In other embodiments, it will be appreciated that the CCU <NUM> can be disposed, for example, on a rooftop or another wall of the transport unit <NUM>. The CCU <NUM> includes a climate control circuit (not shown) for conditioning air to be provided within the climate controlled space <NUM>. The CCU <NUM> can also include a power system (see <FIG>) to power components of the climate control system <NUM> (e.g., a compressor, one or more fans and blowers, one or more sensors, one or more solenoid valves, etc.). The CCU <NUM> can be combined with an air sanitization system (see <FIG>) that is configured to purify air within the climate controlled space <NUM>.

The programmable climate controller <NUM> may comprise a single integrated control unit <NUM> or that may comprise a distributed network of climate controller elements <NUM>, <NUM>. The number of distributed control elements in a given network can depend upon the particular application of the principles described herein. The climate controller <NUM> is configured to control operation of the climate control system <NUM>.

<FIG> illustrates block diagram schematic of a mass-transit vehicle <NUM> that includes an air sanitization system <NUM> and a transport climate control system <NUM>, according to one embodiment. The mass-transit vehicle <NUM> can be, for example, the mass-transit vehicle <NUM> shown in <FIG>. The mass-transit vehicle <NUM> includes a climate controlled space <NUM> for transporting one or more passengers travelling in the mass-transit vehicle <NUM>. The mass-transit vehicle <NUM> can be, for example, a mass-transit bus (e.g., a school bus, a city bus, etc.), a railway vehicle, a subway car, or other mass-transit vehicle that carries passengers.

It will be appreciated that the embodiments described herein with respect to <FIG> are not limited to a mass-transit vehicle and can be used with other transport units including, for example, the vehicle <NUM> shown in <FIG>, the climate controlled transport unit <NUM> shown in <FIG>, etc..

The mass-transit vehicle <NUM> also includes two air delivery ducts <NUM>. The climate controlled space <NUM> can be a passenger compartment for passengers travelling in the mass-transit vehicle <NUM>. The climate controlled space <NUM> can optionally include one or more contamination sensors <NUM> that are configured to monitor air quality (e.g., contamination) within the climate controlled space <NUM>. The one or more contamination sensors <NUM> can include one or more indoor air quality (IAQ) sensors and/or one or more contaminant sensors. In some embodiments, the one or more IAQ sensors can measure, for example, CO<NUM>, total volatile organic compounds, particulate matter, temperature, humidity, etc. within the climate controlled space <NUM>. In some embodiments, the one or more contaminant sensors can measure and identify specific species of contaminants in the air.

The air delivery ducts <NUM> are in airflow communication with both the climate controlled space <NUM> and a climate control unit <NUM> of the transport climate control system <NUM>. The air delivery ducts <NUM> are configured to distribute climate controlled air generated by the climate control unit <NUM> into the climate controlled space <NUM>. Each of the air delivery ducts <NUM> can include multiple openings (not shown) to distribute the climate controlled air substantially evenly within the climate controlled space <NUM>. While the mass-transit vehicle <NUM> includes two air delivery ducts <NUM>, it will be appreciated that the number of air delivery ducts <NUM> can vary as required by the mass-transit vehicle <NUM>. For example, in another embodiment, the mass-transit vehicle <NUM> can include only a single air delivery duct <NUM>. In some embodiments, the mass-transit vehicle <NUM> can also include one or more fresh air dampers (not shown) that can provide fresh air (e.g., ambient air outside of the mass-transit vehicle <NUM>) downstream of an evaporator coil <NUM> of the climate control unit <NUM>. It will be appreciated that the mass-transit vehicle <NUM> can also include one or more doors and/or windows (not shown) that can also introduce fresh air into the climate controlled space <NUM>.

The air sanitization system <NUM> includes a filter <NUM> and an air sanitizer <NUM>. The filter <NUM> can include a filter media that is configured to trap contaminants (e.g., dust particles, etc.) from an airflow passing through the filter <NUM>. In some embodiments, the filter media can be a fabric filter media. In some embodiments, the filter <NUM> can have a multi-layer construction. In some embodiments, an anti-microbial coating can be applied to the filter <NUM>. In some embodiments, the filter <NUM> can be a replaceable filter. It will be appreciated that the size of particles that can be trapped by the filter <NUM> can vary, for example, based on a minimum efficiency reporting values (MERV) rating. In some embodiments, the filter <NUM> can be a MERV <NUM> filter. In some embodiments, the filter <NUM> can be an electrostatic filter.

The air sanitizer <NUM> is configured to purify an airflow directed to the climate controlled space <NUM>. In the embodiment shown in <FIG>, the air sanitizer <NUM> is configured to purify the airflow that has first passed through the filter <NUM> and is passing through a climate control unit <NUM> of the transport climate control system <NUM>. In particular, the air sanitizer <NUM> can attack volatile organic compounds (e.g., airborne viruses and bacteria) in the airflow passing there through. In some embodiments, the air sanitizer <NUM> can be a photo catalytic oxidation (PCO) air purifier that can emit hydroxyls, H<NUM>O<NUM>, ions, or the like that can attack any volatile organic compounds in the airflow passing there through. In particular, the PCO air purifier includes a light-activated catalyst configured to react with organic pollutants to oxidize them into a nontoxic substance.

In some embodiments, the PCO air purifier can be a graphene based PCO air purifier that uses a graphene enhanced titanium oxide catalyst to generate local hydroxyls that can attack volatile organic compounds when they come in contact with the air sanitizer <NUM>. In some embodiments, the PCO air purifier can use an ultraviolet (UV) light to excite and activate the catalyst (e.g., a graphene enhanced titanium oxide catalyst) to begin the chemical reaction. The use of graphene can increase the amount of surface area that the titanium oxide is applied to and thus create more surface area for UV light to shine, thereby increasing the amount of hydroxyls generated. In some embodiments, the UV light can be generated using one or more light emitting diodes (LEDs), one or more mercury lamps, etc. In some embodiments, the UV light can generate -<NUM> light (e.g., when using one or more LEDs, the UV light generated can spike at around <NUM>). An advantage of using LEDs is that they can be safer than other types of light sources such as, for example, mercury light bulbs which can become dangerous should the mercury leak out of or otherwise be removed from the light bulb.

In some embodiments, the PCO air purifier of the air sanitizer <NUM> can include multiple LED panels. In some embodiments, each of the LED panels can include multiple LED circuits. For example, in one embodiment, each LED panel can include four LED circuits. In some embodiments, each of the multiple LED panels of the air sanitizer <NUM> can be independently controlled (e.g., turned ON or OFF) such that not all of the LED panels are ON at the same time. In some embodiments, the air sanitizer <NUM> can be a low voltage device that require, for example, -<NUM> VDC or less in order to operate.

In some embodiments, the air sanitizer <NUM> can include, for example, an ultraviolet germicidal irradiation (UVGI) air purifier, a bi-polar ionizer, a dry hydrogen peroxide generator, an ozone generator, etc..

It will be appreciated that in embodiments where the air sanitizer <NUM> emits, for example, hydroxyls, certain species of contaminants (e.g., halogens such as chlorine, fluorine, etc.) can become more toxic or dangerous when reacting with the hydroxyls (e.g., when oxidized). Accordingly, there can be embodiments whereby the air sanitizer <NUM> can be turned OFF when a level of certain species of contaminants are monitored by one or more contaminant sensors (of the one or more contamination sensors <NUM>).

The air sanitization system <NUM> can optionally include one or more operational sensors <NUM> that can monitor operation of the air sanitizer <NUM> to ensure that the air sanitizer <NUM> is operating properly. In some embodiments, the one or more operational sensors <NUM> are configured to monitor one or more operational parameters of the air sanitizer <NUM>. In some embodiments, the one or more operational sensors <NUM> can include one or more current sensors configured to monitor a current drawn by each of the multiple LED panels and/or each of the multiple LED circuits. In some embodiments, the one or more operational sensors <NUM> can include one or more power sensors configured to monitor a power drawn by each of the multiple LED panels and/or each of the multiple LED circuits. In some embodiments, the one or more operational sensors <NUM> can include one or more UV light sensors configured to monitor an intensity of the UV light. In some embodiments, the one or more operational sensors <NUM> can include one or more lumen sensors configured to monitor a luminance of each of the multiple LED panels and/or each of the multiple LED circuits. In some embodiments, the one or more operational sensors <NUM> can be replaced or used in conjunction with, for example, the one or more contamination sensors <NUM>.

In some embodiments, transport climate control system <NUM> and the air sanitization system <NUM> are configured such that a majority if not an entire portion of the air flow passing over the evaporator coil <NUM> must also pass through the air sanitizer <NUM>. In some embodiments, this can be achieved by mounting the air sanitizer <NUM> directly to the evaporator coil <NUM> such that the air sanitizer <NUM> covers the entire evaporator coil <NUM>. In these embodiments, a majority if not the entire airflow can either pass through the air sanitizer <NUM> first before passing over the evaporator coil <NUM> or pass over the evaporator coil <NUM> first before passing through the air sanitizer <NUM>. In some embodiments, the air sanitizer <NUM> can be located at other locations of the passenger vehicle <NUM> such as anywhere in the air delivery ducts <NUM>. In these embodiments, the air sanitizer <NUM> can also be configured such that a majority if not the entire portion of the air flow directed to the climate controlled space <NUM> passes through the air sanitizer <NUM>.

It will be appreciated that the mass-transit vehicle <NUM> can have high airflow rates within the climate controlled space <NUM>. Applicant has found that hydroxyls, H2O2, ions, or the like that are emitted from typical PCO air purifiers may not survive long enough to travel from, for example, the evaporator coil <NUM>, to the air movement fans/blowers <NUM>, through the air delivery ducts <NUM> and into the climate controlled space <NUM> because of the length of travel and the high airflow rate. By providing an embodiment in which the air sanitizer <NUM> covers the entire evaporator coil <NUM>, the air sanitization system <NUM> can require that all airflow passing over the evaporator coil <NUM> is first directed through the air sanitizer <NUM> to ensure that all conditioned air entering the climate controlled space is purified as it passes through the air sanitizer <NUM>. Accordingly, any hydroxyls, H<NUM>O<NUM>, ions, or the like that are emitted by the air sanitizer <NUM> are not required or intended to travel to and enter the climate controlled space <NUM> in order to attack any volatile organic compounds in the air provided in the climate controlled space <NUM>. This can prevent any harmful volatile organic compounds or ozone from being emitted by the air sanitization system <NUM> into the climate controlled space <NUM>.

The transport climate control system <NUM> includes the climate control unit <NUM>, a controller <NUM>, and a plurality of climate control sensors (not shown). In some embodiments, the transport climate control system <NUM> can also include a human machine interface (HMI) configured to allow a user to manually communicate with and/or provide instructions to the transport climate control system <NUM>, a telematics unit configured to wirelessly connect the transport climate control system <NUM> to user(s) and/or remote server(s) that are remote from the mass-transit vehicle <NUM>. The climate control unit <NUM> includes an evaporator coil <NUM> and a plurality of air movement fans/blowers <NUM>. The climate control unit <NUM> can also include a climate control circuit (not shown) that includes, for example, a compressor configured to compress a working fluid (e.g., a refrigerant), a condenser coil, the evaporator coil <NUM>, and an expansion valve. The climate control circuit can include other components that are known in the art for conditioning air to be directed to a climate controlled space (e.g., one or more valves, a receiver tank, an economizer, working fluid lines, etc.). The climate control unit <NUM> can also include one or more condenser fans configured to direct air in a heat exchange relationship with the condenser coil out of the climate control unit <NUM> into the ambient outside of the mass-transit vehicle <NUM>. The climate control sensors can be provided throughout the mass-transit vehicle <NUM> and monitor one or more climate control parameters. The climate control sensors, for example, can include: a return air temperature sensor that monitors the temperature of air returned from the climate controlled space <NUM> back to the climate control unit <NUM>; a supply air temperature sensor that monitors the temperature of air supplied by the CCU <NUM> into the climate controlled space <NUM>; a humidity sensor that monitors the humidity within the climate controlled space <NUM>; an ambient temperature sensor that monitors the temperature outside of the mass-transit vehicle <NUM>; a compressor suction pressure sensor that monitors a pressure at or near a suction port of the compressor; a compressor discharge pressure sensor that monitors a pressure at or near a discharge port of the compressor; etc..

The air movement fans/blowers <NUM> are configured to direct an airflow into the climate controlled space <NUM>. The air movement fans/blowers <NUM> can be, for example, evaporator fans or blowers that are configured to direct conditioned air that has undergone a heat exchange while passing over the evaporator coil <NUM> into the air delivery ducts <NUM>. It will be appreciated that the number of air movement fans/blowers <NUM> can vary based on the needs of the transport climate control system <NUM>. For example, in some embodiments, the climate control unit <NUM> can include only a single air movement fans/blowers <NUM>. In some embodiments, the air movement fans/blowers <NUM> can operate at multiple non-zero speeds (e.g., a low speed, a medium speed, and a high speed). In some embodiments, the low speed can be in a range of ~<NUM>-<NUM>% of a maximum speed of the air movement fans/blowers <NUM>. In some embodiments, the medium speed can be in a range of -<NUM>-<NUM>% of a maximum speed of the air movement fans/blowers <NUM>. In some embodiments, the high speed can be in a range of -<NUM>-<NUM>% of a maximum speed of the air movement fans/blowers <NUM>. In some embodiments, the air movement fans/blowers <NUM> can be variable speed air movement fans/blowers that operate along a gradient range of non-zero speeds. In some embodiments, the air movement fans/blowers <NUM> can be low voltage devices that require, for example, -<NUM> VDC or less in order to operate. While <FIG> shows two air movement fans/blowers <NUM>, it will be appreciated that in some embodiments the climate control unit <NUM> may include a single air movement fan/blower <NUM> or more than three air movement fans/blowers <NUM>.

The controller <NUM> is configured to control operation of the transport climate control system <NUM> and can also control operation of the air sanitization system <NUM>. In particular, the controller <NUM> is in electrical communication with the air movement fans/blowers <NUM>, the compressor, the one or more condenser fans, the one or more valves, etc. Accordingly, the controller <NUM> can control operation of the transport climate control system by controlling operation of the air movement fans/blowers <NUM>, the compressor, the one or more condenser fans, valves, etc. That is, the controller <NUM> can control whether the air movement fans/blowers <NUM>, the compressor, the one or more condenser fans, one or more valves, etc. are ON or OFF. The controller <NUM> can also control a speed of the air movement fans/blowers <NUM>, the compressor, the one or more condenser fans, etc. Also, the controller <NUM> can control the size of the opening of the one or more valves. The controller <NUM> is configured to receive climate control parameter data from the one or more climate control sensors. It will be appreciated that the controller <NUM> can use the climate control parameter data to control operation of the transport climate control system <NUM> and the air sanitization system <NUM>.

According to the invention, the controller <NUM> also controls the operation of the air sanitizer <NUM>. In particular, the controller <NUM> is in electrical communication with the air sanitizer <NUM>. Accordingly, the controller <NUM> can turn the air sanitizer <NUM> ON or OFF as required and control the amount of power directed to the air sanitizer <NUM>. In some embodiments, the controller <NUM> can selectively turn ON and OFF or limit the power provided to individual LED panels of the air sanitizer <NUM> while the air sanitizer <NUM> is in operation. For example, in some embodiments, the controller <NUM> can selectively turn OFF or limit power directed to a certain number of the LED panels while the air sanitizer <NUM> is in operation in order to reduce the purification capacity of the air sanitizer <NUM>. The controller <NUM> can selectively turn OFF or reduce power to a certain number of the LED panels while the air sanitizer <NUM> is operating in order to reduce energy consumption of the air sanitizer <NUM> during, for example, periods when the mass-transit vehicle <NUM> may be lightly loaded, the risk of contamination in the climate controlled space is low, etc. Also, the controller <NUM> can rotate which of the multiple LED panels are ON and OFF or have reduced power to achieve uniform aging of the air sanitizer <NUM>. In some embodiments, the controller <NUM> is configured to receive operational parameter data from the one or more operational sensors <NUM>.

In some embodiments, the controller <NUM> can control the transport climate control system <NUM> and the air sanitization system <NUM> in a variety of operation modes. These operation modes, for example, can include: a continuous cooling mode whereby the compressor is continuously operating to provide cooling to the climate controlled space <NUM>; a start-stop cooling mode whereby the compressor is periodically turned ON and OFF while providing cooling to the climate controlled space <NUM>; a heating mode to provide heating to the climate controlled space <NUM>; a defrost mode to defrost the evaporator coil <NUM>; an air sanitization mode to purify air in the climate controlled space <NUM> by operating the air movement fans/blowers <NUM> at a high speed; etc..

In some embodiments, the controller <NUM> can be in communication with the mass-transit vehicle <NUM>, a HMI of the transport climate control system <NUM>, a telematics unit of the transport climate control system <NUM>, etc. In some embodiments, the controller <NUM> can receive a communication signal from the mass-transit vehicle <NUM> when the mass-transit vehicle has been turned ON. For example, the controller can receive a signal from the mass-transit vehicle <NUM> that an ignition switch of the mass-transit vehicle <NUM> has been turned ON.

<FIG> shows arrows to illustrate how an airflow is directed through the mass-transit vehicle <NUM>, according to one embodiment. In particular, air in the climate controlled space travels into climate control unit <NUM> and passes through the filter <NUM>. The airflow passing through the filter <NUM> is then directed through the air sanitizer <NUM> to be purified and then over the evaporator coil <NUM> to be conditioned. The air movement fans/blowers <NUM> then directs the purified and conditioned airflow past the evaporator coil and into the air delivery ducts <NUM>. The air delivery ducts <NUM> then return purified and conditioned air back into the climate controlled space <NUM>. One embodiment of a method for operating the air sanitization system <NUM> and the transport climate control system <NUM> in accordance with the invention as claimed is described below with respect to <FIG>. Also, one embodiment of a method for tracking effectiveness of the air sanitization system <NUM> is described below with respect to <FIG>, and is useful for understanding the invention.

<FIG> illustrates a flowchart of a method <NUM> for controlling operation of the air sanitization system <NUM> and the transport climate control system <NUM> shown in <FIG>, according to one embodiment.

It will be appreciated that the embodiments described herein with respect to the method <NUM> shown in <FIG> are not limited to operating an air sanitization system for a mass-transit vehicle and can be used with other transport units including, for example, the vehicle <NUM> shown in <FIG>, the climate controlled transport unit <NUM> shown in <FIG>, etc., noting that the invention as claimed refers to a vehicle having or towing the space in which air is to be purified.

The method <NUM> begins at <NUM> whereby the controller <NUM> receives an ON signal. The ON signal indicates that the mass-transit vehicle <NUM> has been turned ON. For example, in some embodiments, the ON signal can be a signal indicating that an ignition switch of the mass-transit vehicle <NUM> has been turned ON. When the controller <NUM> does not receive the ON signal, the method <NUM> proceeds to <NUM>. When the controller <NUM> receives the ON signal, the method <NUM> proceeds to <NUM>.

At <NUM>, the controller <NUM> instructs one or more components of the transport climate control system <NUM> (e.g., one or more of the air movement fans/blowers <NUM>, the compressor, the one or more condenser fans, the one or more valves, etc.) and the air sanitizer <NUM> to be OFF. For example, in some embodiments, the controller <NUM> can instruct the air movement fans/blowers <NUM>, the compressor, and the air sanitizer <NUM> to be OFF. The method <NUM> then proceeds back to <NUM>.

At <NUM>, the controller <NUM> determines whether an air sanitization mode has been requested. In some embodiments the air sanitization mode can be manually requested by an operator via, for example, a HMI, a telematics unit, a vehicle controller of the passenger vehicle <NUM>, etc. The instruction can then be sent to the controller <NUM> via, for example, a controller area network (CAN) message. In some embodiments, the air sanitization mode can be automatically requested. According to the invention, the controller <NUM> automatically requests the air sanitization mode to operate for a set time period (e.g., <NUM> minutes) once the ON signal indicating that the vehicle having or towing the space is turned ON is received at <NUM>. Thus, for example, the air in the climate controlled space <NUM> can be purified prior to the first trip of the day for the mass-transit vehicle <NUM>. In another implementation, the controller <NUM> can automatically request the air sanitization mode to operate for a set period of time (e.g., <NUM> minutes) during a larger period of time (e.g., every hour). In yet another example, the controller <NUM> can monitor the one or more contamination sensors <NUM>. When the indoor air quality (e.g., contamination) level in the climate controlled space <NUM> exceeds a preset indoor air quality threshold, the controller <NUM> can automatically request the air sanitization mode to purify/clean the air in the climate controlled space <NUM>. Depending on the indoor air quality level, the controller <NUM> can also communicate an alarm/maintenance notification to a user via the HMI, the telematics unit, etc..

When the controller <NUM> determines that the air sanitization mode has been requested, the method <NUM> proceeds to <NUM>. When the controller <NUM> determines that the air sanitization mode has not been requested, the method <NUM> proceeds to <NUM>.

At <NUM>, the controller <NUM> instructs the air sanitization system <NUM> and the transport climate control system <NUM> to operate in the air sanitization mode. In particular, the controller <NUM> instructs the air sanitizer <NUM> to turn ON and instructs the air movement fans/blowers <NUM> to operate at a high speed to increase the speed in which the air sanitization system <NUM> can purify air within the climate controlled space <NUM>. The controller <NUM> can also instruct other components of the transport climate control system <NUM> (e.g., the compressor, the one or more condenser fans, the one or more valves, etc.) to operate as previously instructed, for example, for climate control purposes. If climate control is not required, the controller <NUM> can instruct the other components of the transport climate control system (e.g., the compressor, the one or more condenser fans, the one or more valves, etc.) to be OFF. In some embodiments, the controller <NUM> can also reduce the speed of the air movement fans/blowers <NUM> when desired to conserve energy usage. Accordingly, continuous high speed airflow of purified air can be achieved in the climate controlled space <NUM>.

At <NUM>, the controller <NUM> determines whether climate control is required for conditioning air in the climate controlled space <NUM>. In some embodiments, the controller <NUM> can obtain climate control parameter data from the one or more climate control sensors to monitor one or more climate control parameters. The climate control parameters can be used, at least in part, to determine whether conditioned air is required in the climate controlled space <NUM>. The climate control parameters, for example, can include: a return air temperature of air returned from the climate controlled space <NUM> back to the climate control unit <NUM>; a supply air temperature of air supplied by the CCU <NUM> into the climate controlled space <NUM>; a humidity within the climate controlled space <NUM>; an ambient temperature outside of the mass-transit vehicle <NUM>; a compressor suction pressure at or near a suction port of the compressor; a compressor discharge pressure at or near a discharge port of the compressor; etc. The one or more climate control parameters can be compared to a threshold value to determine whether climate control within the climate controlled space <NUM> is required. For example, the return air temperature can be compared to a desired setpoint temperature or an ambient temperature. When the difference between the return air temperature and the desired setpoint temperature (or the ambient temperature) is outside of a boundary range (e.g., <NUM> (<NUM>° Fahrenheit)), the controller <NUM> determines that climate control is required. When the difference between the return air temperature and the desired setpoint temperature is inside of the boundary range, the controller <NUM> determines that climate control is not required. In another example, the compressor suction pressure or the compressor discharge pressure can be compared to a preset pressure threshold. When the compressor discharge pressure or the compressor suction pressure exceeds the preset pressure threshold, the controller <NUM> can determine that climate control is required. When the compressor discharge pressure or the compressor suction pressure does not exceed the preset pressure threshold, the controller <NUM> can determine that climate control is not required.

When the controller <NUM> determines that climate control is required for conditioning air in the climate controlled space <NUM>, the method <NUM> proceeds to <NUM>. When the controller <NUM> determines that climate control is not required for conditioning air in the climate controlled space <NUM>, the method <NUM> proceeds to <NUM>.

At <NUM>, the controller <NUM> determines the amount of climate control required for conditioning the climate controlled space <NUM> and sends appropriate instructions to the components of the transport climate control system <NUM> (e.g., the air movement fans/blowers <NUM>, the compressor, the one or more condenser fans, the one or more valves, etc.). This includes the controller <NUM> instructing the air movement devices <NUM> to be ON and operating at a required non-zero speed (e.g., a low speed, a medium speed, a high speed, etc.). Accordingly, the transport climate control system <NUM> can provide passenger comfort to passengers in the climate controlled space <NUM>. The controller <NUM> also instructs the air sanitizer <NUM> to be ON to purify the conditioned air entering the climate controlled space <NUM>. In some embodiments, the controller <NUM> can also monitor the one or more contamination sensors <NUM> and increase the speed of the air movement fans/blowers <NUM> when the indoor air quality level in the climate controlled space <NUM> exceeds a preset indoor air quality threshold. Depending on the indoor air quality level, the controller <NUM> can also communicate an alarm/maintenance notification to a user via the HMI, the telematics unit, etc. In some embodiments, the controller <NUM> can also reduce the speed of the air movement fans/blowers <NUM> when desired to conserve energy usage. The method <NUM> then proceeds back to <NUM>.

At <NUM>, the controller <NUM> instructs the air sanitizer <NUM> to turn ON and instructs the air movement fans/blowers <NUM> to operate at a predefined speed. In some embodiments, the predefined speed can be a low speed of the air movement fans/blowers <NUM>. In some embodiments, the predefined speed can be a speed that is lower than the high speed of the air movement fans/blowers <NUM>. The controller <NUM> can also instruct one or more other components of the transport climate control system <NUM> (e.g., one or more of the compressor, the one or more condenser fans, the one or more valves, etc.) to turn OFF. For example, in some embodiments, the controller <NUM> can instruct the compressor to be OFF. Accordingly, purified air can still be directed to the climate controlled space <NUM> without requiring conditioning of the purified air. In some embodiments, the controller <NUM> can also monitor the one or more contamination sensors <NUM> and increase the speed of the air movement fans/blowers <NUM> when the indoor air quality level in the climate controlled space <NUM> exceeds a preset indoor air quality threshold. Depending on the indoor air quality level, the controller <NUM> can also communicate an alarm/ maintenance notification to a user via the HMI, the telematics unit, etc. The method <NUM> then proceeds back to <NUM>.

In some embodiments, throughout the method <NUM>, the controller <NUM> can also monitor the one or more contamination sensors <NUM> for specific problematic species of particles (e.g., halogen particles) and turn OFF the air sanitizer <NUM> when a certain level of a problematic specie of particles is identified. Also, in some embodiments, throughout the method <NUM>, the controller <NUM> can monitor the one or more contamination sensors <NUM> for a total level of contamination within the climate controlled space and turn OFF the air sanitizer <NUM> when the monitored level of contamination within the climate controlled space exceeds a clean air threshold.

It will be appreciated that in some embodiments, <NUM> and <NUM> can be optional such that when the controller <NUM> receives the ON signal, the method <NUM> can proceed directly to <NUM>. Also, in some embodiments, when the controller <NUM> receives the ON signal, the method <NUM> can proceed directly to <NUM> to run the air movement fans/blowers <NUM> and power ON the air sanitizer <NUM> and then proceed from <NUM> to <NUM> to determine whether climate control is required.

An advantage of the method <NUM> is that the air movement fans/blowers <NUM> is controlled to be operating whenever the mass-transit vehicle <NUM> is turned ON in order to provide constant airflow movement within the climate controlled space. Another advantage of the method <NUM> is that the air sanitizer <NUM> is always ON (i.e., in use) when there is airflow movement within the climate controlled space. Accordingly, purified air can be provided to the climate controlled space <NUM> whenever the mass-transit vehicle <NUM> is ON regardless of whether the transport climate control system <NUM> is conditioning the airflow. Also, it will be appreciated that in some embodiments, when the air sanitizer <NUM> is in operation (e.g., at <NUM>, <NUM> and <NUM>) the controller <NUM> can selectively turn ON and OFF or reduce power to the individual LED panels of the air sanitizer <NUM> in order to reduce energy consumption of the air sanitizer <NUM>.

<FIG> illustrates a flowchart of a method <NUM> for tracking effectiveness of the air sanitization system <NUM> shown in <FIG>, according to one embodiment which is useful for understanding the invention.

It will be appreciated that the embodiments described herein with respect to the method <NUM> shown in <FIG> are not limited to operating an air sanitization system for a mass-transit vehicle and can be used with other transport units including, for example, the vehicle <NUM> shown in <FIG>, the climate controlled transport unit <NUM> shown in <FIG>, etc..

The method <NUM> begins at <NUM> whereby the controller <NUM> determines whether the air sanitizer <NUM> has been instructed to operate. When the controller <NUM> determines that the air sanitizer <NUM> has been instructed to operate, the method <NUM> proceeds to <NUM>. When the controller <NUM> determines that the air sanitizer <NUM> has been instructed to operate, the method <NUM> proceeds to <NUM>. When the controller <NUM> determines that the air sanitizer <NUM> has not been instructed to operate, the method <NUM> returns to <NUM>.

At <NUM>, the controller <NUM> monitors one or more operational parameters of the air sanitizer <NUM>. In some embodiments, the controller <NUM> can monitor the one or more operational parameters of the air sanitizer <NUM> by receiving operational parameter data from the one or more operational sensors <NUM> and/or the one or more contamination sensors <NUM>. The one or more operational parameters can, for example, include: current draw data from the air sanitizer <NUM> as a whole and/or each of the multiple LED panels and/or each of the multiple LED circuits; power draw data from the air sanitizer <NUM> as a whole and/or each of the multiple LED panels and/or each of the multiple LED circuits; light intensity data of each of the one or more UV lights; luminance data of each of the multiple LED panels and/or each of the multiple LED circuits; indoor air quality data within the climate controlled space <NUM>; etc. The method <NUM> then proceeds to <NUM>.

At <NUM>, the controller <NUM> calculates an amount or percentage in loss of efficacy of the air sanitizer <NUM> based on the monitored operational data obtained at <NUM>. For example, in some embodiments, the monitored current/power draw data can be compared to an expected current/power draw of the air sanitizer <NUM>. The difference between the monitored current/power draw and the expected current/power draw can be used to calculate a percentage in current/power reduction of the air sanitizer <NUM> compared to the amount of current/power the air sanitizer <NUM> is expected to draw. In another example, the monitored current/power draw data can be used to calculate a number of LED circuits that have failed. In yet another example, the controller <NUM> can calculate the loss of indoor air quality amount or percentage based on the indoor quality data monitored at <NUM>. The method <NUM> then proceeds to <NUM>.

At <NUM>, the controller <NUM> determines whether the air sanitization system <NUM> is operating effectively. In some embodiments, the controller <NUM> can determine whether the air sanitization system <NUM> is operating effectively by comparing the amount or percentage in loss of efficacy of the air sanitizer <NUM> calculated at <NUM> to a preset efficacy threshold. For example, the calculated percentage in current/power reduction can be compared to a preset current/power reduction threshold. In another example, the number of failed LED circuits calculated at <NUM> can be compared to a preset failed LED circuit threshold. In yet another example, the loss of indoor air quality amount or percentage can be compared a preset indoor air quality threshold. Also, in another example, the calculated percentage in light intensity or luminance reduction can be compared to a preset light intensity or luminance threshold. When the loss of efficacy of the air sanitizer <NUM> exceeds the preset efficacy threshold, the controller determines that the air sanitization system <NUM> is not operating effectively and the method <NUM> proceeds to <NUM>. When the loss of efficacy of the air sanitizer <NUM> does not exceed the preset efficacy threshold, the controller determines that the air sanitization system <NUM> is operating effectively and the method <NUM> proceeds to <NUM>.

At <NUM>, the controller <NUM> generates and displays an alarm/maintenance notification to a user via, for example, the HMI, the telematics unit, etc. In some embodiments, the controller <NUM> can instruct the HMI of the transport climate control system <NUM> to display an alarm/maintenance notification on a display of the HMI. In some embodiments, the controller <NUM> can instruct the telematics unit of the transport climate control system <NUM> to send an alarm/maintenance notification to a user via a wireless communication (e.g., a text message, an email, SMS message, etc.) so that the, for example, alarm/maintenance notification is displayed on the user's mobile device. In some embodiments, the alarm/maintenance notification can include a percentage of the air sanitizer <NUM> that is in operation. The method <NUM> then proceeds back to <NUM>.

At <NUM>, the controller <NUM> takes no further action is taken as the controller <NUM> determined at <NUM> that the air sanitization system <NUM> is operating effectively. The method <NUM> returns to <NUM>.

<FIG> is a schematic diagram of a refrigerant circuit <NUM>, according to an embodiment. The refrigerant circuit <NUM> generally includes a compressor <NUM>, a condenser <NUM>, an expansion device <NUM>, and an evaporator <NUM>. An "expansion device" as described herein may also be referred to as an expander. In an embodiment, the expander may be an expansion valve, expansion plate, expansion vessel, orifice, or the like, or other such types of expansion mechanisms. It should be appreciated that the expander may be any suitable type of expander used in the field for expanding a working fluid to cause the working fluid to decrease in pressure and temperature. In an embodiment, the evaporator <NUM> can be a microchannel heat exchanger. The refrigerant circuit <NUM> is an example and can be modified to include additional components. For example, in an embodiment, the refrigerant circuit <NUM> can include other components such as, but not limited to, an economizer heat exchanger, one or more flow control devices, a receiver tank, a dryer, a suction-liquid heat exchanger, or the like.

The refrigerant circuit <NUM> can generally be applied in a variety of systems used to control an environmental condition (e.g., temperature, humidity, air quality, or the like) in a space (generally referred to as a conditioned space). Examples of such systems include, but are not limited to, HVACR systems, transport refrigeration systems, or the like. In an embodiment, a HVACR system can be a rooftop unit or a heat pump air-conditioning unit.

The compressor <NUM>, condenser <NUM>, expansion device <NUM>, and evaporator <NUM> are fluidly connected. In an embodiment, the refrigerant circuit <NUM> can be configured to be a cooling system (e.g., an air conditioning system) capable of operating in a cooling mode. In an embodiment, the refrigerant circuit <NUM> can be configured to be a heat pump system that can operate in both a cooling mode and a heating/defrost mode. A centrifugal fan (not shown, described later) can be provided to a heat exchanger such as the condenser <NUM> and/or the evaporator <NUM>.

It will be appreciated that the centrifugal fans are disclosed in e.g., the <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; and <CIT>.

The refrigerant circuit <NUM> can operate according to generally known principles. The refrigerant circuit <NUM> can be configured to heat and/or cool a liquid process fluid (e.g., a heat transfer fluid or medium (e.g., a liquid such as, but not limited to, water or the like)), in which case the refrigerant circuit <NUM> may be generally representative of a liquid chiller system. The refrigerant circuit <NUM> can alternatively be configured to heat and/or cool a gaseous process fluid (e.g., a heat transfer medium or fluid (e.g., a gas such as, but not limited to, air or the like)), in which case the refrigerant circuit <NUM> may be generally representative of an air conditioner and/or heat pump.

In operation, the compressor <NUM> compresses a working fluid (e.g., a heat transfer fluid (e.g., refrigerant or the like)) from a relatively lower pressure gas to a relatively higher-pressure gas. The relatively higher-pressure gas is also at a relatively higher temperature, which is discharged from the compressor <NUM> and flows through the condenser <NUM>. In accordance with generally known principles, the working fluid flows through the condenser <NUM> and rejects heat to the process fluid (e.g., water, air, etc.), thereby cooling the working fluid. The cooled working fluid, which is now in a liquid form, flows to the expansion device <NUM>. The expansion device <NUM> reduces the pressure of the working fluid. As a result, a portion of the working fluid is converted to a gaseous form. The working fluid, which is now in a mixed liquid and gaseous form flows to the evaporator <NUM>. The working fluid flows through the evaporator <NUM> and absorbs heat from the process fluid (e.g., a heat transfer medium (e.g., water, air, etc.)), heating the working fluid, and converting it to a gaseous form. The gaseous working fluid then returns to the compressor <NUM>. The above-described process continues while the heat transfer circuit is operating, for example, in a cooling mode (e.g., while the compressor <NUM> is enabled).

<FIG> is a perspective view, partially cutaway, illustrating an air handling unit (air handler) <NUM> of an HVACR system having a centrifugal fan <NUM>, according to an embodiment.

The unit <NUM> includes an enclosure <NUM>. In one embodiment, the enclosure <NUM> can be a generally rectangular cabinet having a first end wall defining an air inlet opening <NUM> (to allow air to flow into an internal space of the enclosure <NUM>) and a second end wall defining an air outlet opening (not shown, to allow air to flow out of the enclosure <NUM> via an air outlet (that overlaps with the air outlet opening) of the centrifugal fan <NUM>. In <FIG>, a side wall of the enclosure <NUM> is cutaway and the internal space of the enclosure <NUM> is shown.

The unit <NUM> also includes a primary filter <NUM> and a secondary filter <NUM>. In one embodiment, the primary filter <NUM> and the secondary filter <NUM> can be one filter. It will be appreciated that the primary filter <NUM> and/or the secondary filter <NUM> can be a porous device configured to remove impurities or solid particles from air flow passed through the device.

In one embodiment, outer surface(s) (e.g., the entire surface facing the airflow and/or the entire surface opposite to the surface facing the airflow) of the secondary filter <NUM> (and/or the primary filter <NUM>) can be covered (or coated or sintered) with e.g., a photocatalyst layer. A light source (not shown) can be added in the enclosure <NUM> to emit light on the photocatalyst layer disposed on the outer surface(s) of the filter where the air passes through. This embodiment provides a solution to achieve photocatalytic oxidation and/or ultraviolet germicidal irradiation on surfaces of the filter(s). In this embodiment, more space is needed (e.g., for disposing the light source) in the enclosure <NUM> (and thus a length of the enclosure may need to be increased, or the space of other components within the enclosure <NUM> may be occupied by the light source), air pressure drop may occur (e.g., due to the added resistance to the air because of the added photocatalyst layer to the filter) on the outer surface(s) of the filter, and/or a sealed installation may be needed (e.g., for the light source to prevent e.g., UV light such as UVC light from being leaked out from the enclosure <NUM>). In this embodiment, the efficiency and efficacy of one-time filtration and/or sterilization of air can be optimal because e.g., the outer surface(s) of the filter may cover the entire airflow passing through the filter.

The unit <NUM> further includes a component (e.g., a coil) <NUM>. In one embodiment, the component <NUM> can be an air conditioning evaporator coil disposed in the flow path of air passing from the air inlet opening <NUM> to the air outlet opening of the enclosure <NUM> (which is also the air outlet of the fan <NUM>). It will be appreciated that the component <NUM> can be different types in that the working fluid can be e.g., refrigerant, water, or the like. For example, when the working fluid is refrigerant, the component <NUM> can be an evaporator coil for cooling, and/or can be a condenser coil for heating. For example, when the working fluid is water, the component <NUM> can be tube(s) for chilled water to go through for cooling, and can be tube(s) for hot water to go through for heating.

The unit <NUM> also includes a humidifier <NUM> configured to add moisture to the air to prevent dryness that can cause irritation in many parts of the human body or to increase humidity in the air.

Also the unit <NUM> includes a fan (or blower) <NUM>. In one embodiment, the fan <NUM> can be a centrifugal fan having electric drive motor (not shown) to drive the fan <NUM> (e.g., to drive a shaft of the fan <NUM>, to rotate the impeller of the fan <NUM>). It will be appreciated that a centrifugal fan is a mechanical device for moving air or other gases toward the outlet of the fan in a direction at an angle (e.g., perpendicular) to the incoming air from the inlet of the fan. A centrifugal fan often contains a ducted housing to direct outgoing air in a specific direction or across a heat sink. The centrifugal fan can increase the speed and volume of an air stream with rotating impellers.

The terminology used in this Specification is intended to describe particular embodiments and is not intended to be limiting. The terms "a," "an," and "the" include the plural forms as well, unless clearly indicated otherwise. The terms "comprises" and/or "comprising," when used in this Specification, specify the presence of the stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, and/or components.

Claim 1:
A method for purifying air within a climate controlled space (<NUM>), the method comprising:
a controller (<NUM>) determining whether an ON signal is received, wherein the ON signal indicates that a vehicle having or towing the space is turned ON;
characterized by:
upon determining that the ON signal is received, the controller instructing:
an air sanitizer (<NUM>) of an air sanitization system to turn ON for a set time period to purify an airflow passing through the air sanitization system,
an air movement fan/blower (<NUM>) of a climate control system (<NUM>) to operate in order to direct the airflow into the climate controlled space, and
upon determining that the ON signal is not received, the controller instructing the air movement fan/blower and the air sanitizer to be OFF.