FORM 2
THE PATENTS ACT 1970
[39 OF 1970]
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10; rule 13]
TITLE: “AN EXHAUST HEAT EXCHANGER FOR A VEHICLE AND AN AIR CONDITIONING SYSTEM THEREOF”
Name and Address of the Applicant:
TATA MOTORS LIMITED having its address at: Bombay House, 24 Homi
Mody Street, Hutatma Chowk, Mumbai 400 001, Maharashtra, India.
Nationality: Indian
The following specification particularly describes the invention and the manner in which it is to be performed.

TECHNICAL FIELD
Present disclosure, in general, relates to a field of automobiles. Particularly, but not exclusively, the present disclosure relates to a heating, ventilation and air conditioning system in a vehicle. Further, embodiments of the present disclosure relate to an exhaust heat exchanger for carrying out the heating, ventilation and air conditioning system in a vehicle.
BACKGROUND OF THE DISCLOSURE
Automobile air conditioning system generally includes vapour compression based air conditioning systems, wherein the compressor is driven by a fossil-fuel via gear drives or belt drives and in some configurations driven through electric power from a battery pack or alternator of the vehicle. In the process, the refrigerant goes through various phases of refrigeration cycle with a compressor, a condenser, a thermal expansion valve and an evaporator to complete a refrigeration cycle, in order to cool the space inside the vehicle. In some vehicles, adsorption based air conditioning systems are used to cool and heat the air inside the vehicle.
In conventional vehicles, adsorption based air conditioning is employed as an energy-efficient alternative to conventional refrigeration and air conditioning systems. Such air conditioning systems are often driven using waste heat to heat water, such as waste heat from exhaust or steam from industrial processes or heat directly generated from solar panels or other devices. However, such air conditioning systems often employ additional heating devices to heat the cabin air, for example, when the vehicle is in cold environments or at higher altitudes. Such additional heating devices consume additional power and may lead to reduction in overall efficiency of the air conditioning system and may incur additional expenses.
The present disclosure is directed to overcome one or more limitations stated above or any other limitations associated with the conventional mechanisms.
The drawbacks/difficulties/disadvantages/limitations of the conventional techniques explained in the background section are just for exemplary purpose and the disclosure would never limit its scope only such limitations. A person skilled in the art would understand that this disclosure and below mentioned description may also solve other problems or overcome the other drawbacks/disadvantages of the conventional arts which are not explicitly captured above.
SUMMARY OF THE DISCLOSURE

One or more shortcomings of the prior art are overcome by a system, a heat exchanger and a system as claimed and additional advantages are provided through the system and the method as claimed in the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.
In one non-limiting embodiment of the present disclosure a heat exchanger for a heating ventilation and air conditioning system in a vehicle is disclosed. The exhaust heat exchanger comprises a housing is connectable to a portion of a vehicle body. The housing is adapted to receive exhaust gas from an exhaust manifold of an engine of the vehicle. The exhaust heat exchanger comprises a plurality of fins defined on the housing and extending downwardly away from the housing and exposed to cabin air. The plurality of fins exchange heat with the cabin air to heat the cabin air of the vehicle.
In an embodiment, the housing is configured with a plurality of conduits on an inner surface along a lateral axis to define at least one flow path in the housing.
In an embodiment, the housing is defined with an inlet at one end to receive the exhaust gas from the engine, wherein the housing is defined with an outlet on another end to vent out the exhaust gas after heat exchange.
In an embodiment, the plurality of grooves are configured to guide the exhaust gas from the inlet to the outlet in a controlled directional flow.
In another non-limiting embodiment of the present disclosure, a heating ventilating and air conditioning system for a vehicle is disclosed. The system comprises an exhaust heat exchanger connectable to an exhaust manifold of an engine. The exhaust heat exchanger comprises a housing that is connectable to a portion of a vehicle body. The housing is adapted to receive exhaust gas from an exhaust manifold of an engine of the vehicle. The exhaust heat exchanger comprises a plurality of fins defined on the housing and extending downwardly away from the housing and exposed to cabin air. The plurality of fins exchange heat with the cabin air to heat the cabin air of the vehicle. The system includes a heat exchanger fluidly coupled to the exhaust manifold of the vehicle to receive and exchange heat with the exhaust gas of the vehicle. The system includes an evaporator fluidly coupled to a compressor to receive a refrigerant, the evaporator is fluidly coupled to the exhaust heat exchanger to selectively receive and cool the

cabin air. The system includes one or more sensors disposable in the vehicle configured to sense and transmit at least one signal corresponding to at least one cooling parameter associated with the cabin air. The system includes a control unit communicatively coupled to the evaporator and the one or more sensors. The control unit is configured to receive the at least one signal from the one or more sensors. The control unit determines a condition for heating the cabin air. The control unit regulates a valve connected between the exhaust manifold and the exhaust heat exchanger to selectively allow the exhaust gas into the exhaust heat exchanger to heat the cabin air.
In an embodiment, the heating, ventilating, and air conditioning system is an adsorption-based cooling system.
In another non-limiting embodiment of the present disclosure, a method for operating a heating ventilating and air conditioning system in a vehicle is disclosed. The method comprises receiving, by a control unit, at least one signal from one or more sensors to at least one cooling parameter associated with the cabin air. The control unit then determines a condition for heating the cabin air based on the at least one cooling parameter. The control unit regulates a valve connected between an exhaust manifold and an exhaust heat exchanger to selectively allow exhaust gas into the exhaust heat exchanger to heat the cabin air based on the comparison of the at least one cooling parameter.
In an embodiment, the method comprises determining, by the control unit, the condition for heating the cabin air based on comparing the at least one cooling parameter from the at least one signal transmitted by the one or more sensors with a predetermined set of values corresponding to the at least one cooling parameter.
In an embodiment, the method comprises determining, by the control unit, difference in the at least one cooling parameter received from the at least one signal with the predetermined set of values and actuating, by the control unit, an evaporator selectively to cool the cabin air received from the exhaust heat exchanger, wherein the valve is regulated to close to prevent heating of the cabin air in the exhaust heat exchanger.
In an embodiment, the method comprises comparing, by the control unit, the determined difference between the at least one cooling parameter and the at least one signal with a predetermined difference value.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The novel features and characteristic of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:
Figure 1 is a side view of a vehicle depicting a heating ventilation and air conditioning system, in accordance with an embodiment of the present disclosure.
Figure 2 is a schematic diagram depicting a heating ventilation and air conditioning system, in accordance with an embodiment of the present disclosure.
Figure 3a is a perspective view of an exhaust heat exchanger, in accordance with an embodiment of the present disclosure.
Figure 3b is a perspective view depicting conduits of the exhaust heat exchanger, in accordance with an embodiment of the present disclosure.
Figure 3c is another perspective view depicting an inlet of the exhaust heat exchanger, in accordance with an embodiment of the present disclosure.
Figure 3d is a front view of the exhaust heat exchanger, in accordance with an embodiment of the present disclosure.
Figure 3e is a side view of the exhaust heat exchanger, in accordance with an embodiment of the present disclosure.
Figure 3f is a top view of an exhaust heat exchanger, in accordance with an embodiment of the present disclosure.

Figure 3g is a bottom view of an exhaust heat exchanger, in accordance with an embodiment of the present disclosure.
Figure 4 is a flow diagram depicting a method for operating a heating ventilating and air conditioning system, in accordance with an embodiment of the present disclosure.
The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the system and method illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION
While the embodiments in the disclosure are subject to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the figures and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.
The terms “comprises”, “comprising”, or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusion, such that a device, assembly, system, method that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system, or assembly, or device. In other words, one or more elements in a system proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or method.
Embodiments of the present disclosure discloses a heat exchanger for a heating ventilation and air conditioning system in a vehicle. The exhaust heat exchanger comprises a housing is connectable to a portion of a vehicle body. The housing is adapted to receive exhaust gas from an exhaust manifold of an engine of the vehicle. The exhaust heat exchanger comprises a plurality of fins defined on the housing and extending downwardly away from the housing and exposed to cabin air. The plurality of fins exchange heat with the cabin air to heat the cabin air of the vehicle. With such configuration, the exhaust heat exchanger may eliminate or reduce need for external heating devices for heating cabin air in a vehicle.

The disclosure is described in the following paragraphs with reference to Figures 1 to 4. In the figures, the same element or elements which have same functions are indicated by the same reference signs. One skilled in the art would appreciate that the exhaust heat exchanger, the heating ventilation and air conditioning system and the method as disclosed in the present disclosure may be used in any vehicle including but not liming to heavy commercial vehicles and heavy passenger vehicles and the like. The system and the method of the present disclosure may also be implemented in vehicles having adsorption based heating ventilation and air conditioning systems without deviating from the principles of the present disclosure.
Figure 1 is an exemplary embodiment of the present disclosure which illustrates a side view of a vehicle (300). The vehicle (300) comprises a chassis [not shown explicitly in figures], an engine [not shown explicitly in figures] mounted to the chassis, an exhaust manifold coupled to the engine configured to receive exhaust gas from the engine. The vehicle (300) comprises an exhaust valve (211) coupled to the exhaust manifold to selectively allow flow of the exhaust gas to the environment or into an exhaust conduit to a heating ventilation and air conditioning system (200) of the vehicle (300) as can be seen in Figure 1. In an embodiment, the heating ventilation and air conditioning system (200) may operate in two modes such as a cooling mode configured to reduce temperature and cool cabin air of the vehicle (300) and a heating mode, where the heating ventilation and air conditioning system (200) increases temperature of the cabin air.
Referring now to Figures 1 and 2, the heating ventilation and air conditioning system (200) includes an exhaust cooling circuit comprising a heat exchanger (201) fluidly coupled to the exhaust manifold of the vehicle (300). In the illustrative embodiment, the heating ventilation and air conditioning system (200) is an adsorption based cooling system (200). The heat exchanger (201) receives and exchanges heat with the exhaust gas of the vehicle (300) where, the heat exchanger (201) may utilize any environment friendly refrigerant fluid with low Global Warming Potential (GWP) value and do not lead to ozone layer depletion. The refrigerant fluid may include, but not limited to, Ammonia, Hydrogen gas, water and the like. The heat exchanger (201) may receive cabin air from a cabin of the vehicle (300) through a recirculation grill of the vehicle (300). The heat exchanger (201) may include, but not limited to, a counter flow heat exchanger (201), a spiral heat exchanger (201) and the like. The heating ventilation and air conditioning system (200) includes an evaporator (202) fluidly coupled to a compressor to receive a refrigerant. The evaporator (202) is fluidly coupled to an exhaust heat exchanger

(100) to selectively receive and cool the cabin air by exchanging heat with the refrigerant received from the compressor. In an embodiment, the refrigerant may include any conventional refrigerant used in air conditioning systems, including but not limited to R134a. The refrigerant exchanges heat with the cabin air to cool down and recirculate into the cabin by a blower through air vents of the vehicle (300) as can be seen in Figure 2.
Referring now to figures 3a to 3c, the heating ventilation and air conditioning system (200) includes the exhaust heat exchanger (100) fluidly coupled between the exhaust cooling circuit and the evaporator (202). The exhaust heat exchanger (100) includes a housing (1) connectable to a portion of a vehicle (300) body. In an embodiment, the housing (1) may be coupled to a top portion of the vehicle (300) as can be seen in Figure 1 and accommodated within an enclosure of the heating ventilation and air conditioning system (200). Such position of the housing (1) shall not be construed as a limitation as the position may be varied based on design requirements of the heating ventilation and air conditioning system (200). In an embodiment, the housing (1) is structured in a semi-disc shaped profile as can be seen in Figure 3a to be accommodated in the heating ventilation and air conditioning system (200) by occupying minimal volume.
Referring now to Figures 3d to 3e, the housing (1) is adapted to receive exhaust gas from an exhaust manifold of an engine of the vehicle (300). The housing (1) is defined with an inlet (4) at one end to receive the exhaust gas from the engine. The housing (1) is defined with an outlet on another end to vent out the exhaust gas after heat exchange. In an embodiment, the profile of the housing (1) may be selected from cuboidal, spherical and the like. In the illustrative embodiment, the housing (1) is depicted in the semi-disc profile to maximize surface area for heat exchange between the cabin air and the exhaust gas and to occupy minimal space in the heating ventilation and air conditioning system (200). In the illustrative embodiment, the inlet (4) is depicted on a top surface of the housing (1) fluidly coupled to the exhaust conduit of the vehicle (300) to receive the exhaust gas as can be seen in Figure 3d. Whereas, the outlet is depicted on a circumference of the disc-shaped profile of the housing (1) to vent the exhaust gas from the housing (1) after exchanging heat with the cabin air as can be seen in Figure 3e.
Referring now to Figures 3f and 3g, the exhaust heat exchanger (100) includes a plurality of fins (2) defined on the housing (1) extending downwardly away from the housing (1) as can be seen clearly in Figure 3g. The fins are depicted to extend along length of the exhaust heat exchanger (100) as can be clearly seen Figure 3a on a bottom surface of the housing (1). In an

embodiment, the fins may be configured on the top surface of the housing (1) abutting the inlet (4) for better heat exchange with the cabin air, where the cabin air may flow along the top surface as well as the bottom surface of the exhaust heat exchanger (100). For the sake of explanation, the exhaust heat exchanger (100) is depicted with fins only on the bottom surface as can be seen in Figure 3g and the same shall not be construed as a limitation.
The housing (1) is configured with a plurality of conduits (3) on an inner surface along a lateral axis (AA’) as can be clearly seen in Figure 3b. The conduits (3) may be defined by a plurality of grooves or a plurality of solid blocks separated by a predefined space as can be seen in Figure 3b to define the conduits (3). The conduits (3) allow flow of the exhaust gas along the inner surface of the housing (1) to define at least one flow path in the housing (1) to maximize amount of heat exchange with the fins. The fins are exposed to cabin air wherein the plurality of fins (2) exchange heat with the cabin air to heat the cabin air of the vehicle (300). In the illustrative embodiment, the conduits (3) are defined radially extending from a center portion of the inner surface toward the peripheral portion and fluidly coupled to the outlet to vent the exhaust gas. The flow path defined by the conduits (3) may be varied based on design requirements of the exhaust heat exchanger (100) and the heating ventilation and air conditioning system (200) of the vehicle (300) and the same shall not be considered a limitation. In an embodiment, the flow path defined along a portion of the peripheral region of the inner surface as can be seen in Figure 3b, where the flow path defined by the conduits (3) functions as a muffler to reduce noise due to flow of the exhaust gas while enhancing heat transfer efficiency of the exhaust heat exchanger (100).
Referring again to Figures 1 and 2, the heating ventilating and air conditioning system (200) includes one or more sensors (203) disposable in the vehicle (300) configured to sense and transmit at least one signal corresponding to at least one cooling parameter associated with the cabin air. The sensors (203) may include temperature sensors (203), temperature and humidity sensors (203) and the like. In the illustrative embodiment, the sensors (203) are depicted as temperature sensors (203) to sense temperature in the cabin and transmit signal corresponding to temperature in the cabin of the vehicle (300). In an embodiment the sensors (203) are disposed on a top surface of the body of the vehicle (300) as can be seen in Figure 1. The position and number of sensors (203) shall not be construed as a limitation, as the same may be varied based on requirement of the vehicle (300).

Further, the heating ventilating and air conditioning system (200) control unit (204) communicatively coupled to the evaporator (202) and the one or more sensors (203). The control unit (204) may be communicatively coupled to the exhaust valve (211) of the vehicle (300) and the valve (205) of the heating ventilating and air conditioning system (200) to regulate the operation of the valve (205) and the exhaust valve (211) selectively. The control unit (204) is configured to receive the signal from the sensors (203) corresponding to at least one cooling parameter i.e., temperature of the cabin air and determine a condition for hearting the cabin air based on the temperature of the cabin air. Upon determining the condition, the control unit (204) regulates the valve (205) connected between the exhaust manifold and the exhaust heat exchanger (100) to selectively allow the exhaust gas into the exhaust heat exchanger (100) to heat the cabin air. The control unit (204) compares the at least one cooling parameter from the signal transmitted by the sensors (203) with a predetermined set of values corresponding to the cooling parameter. The control unit (204) may regulate the valve (205) to allow flow of the exhaust gas when the cooling parameter is below the predetermined set of value. For example, the control unit (204) may regulate the valve (205) to allow flow of the exhaust gas when the temperature of the cabin air is below the predetermined temperature value. The predetermined temperature value may include a minimum temperature, where heating of cabin air is required to provide optimal temperature within the cabin of the vehicle (300).
The control unit (204) may regulate the valve (205) to restrict the flow of the exhaust gas when the cooling parameter is above the predetermined set of value. For example, the control unit (204) may regulate the valve (205) to allow flow of the exhaust gas when the temperature of the cabin air is above the predetermined temperature value. The predetermined temperature value may include a minimum temperature, where heating of cabin air is required to provide optimal temperature within the cabin of the vehicle (300). The control unit (204) is configured to determine a difference in the cooling parameter received from the at least one signal with the predetermined set of values. For example, the control unit (204) is configured to determine a difference between the temperature received from the signal and the predetermined temperature value.
Further, the control unit (204) is configured to compare the determined difference between the temperature and the predetermined temperature with a predetermined difference value to determine the condition for heating the cabin air. For example, as shown in below table 1, the

control unit (204) determines the condition for heating the cabin air only when the determined difference is less than or equal to the predetermined difference or when the temperature from the signal is less than the predetermined temperature value. In an embodiment, the control unit (204) is configured to regulate the exhaust cooling circuit, the compressor, and the valve (205) based on the determined condition. For example, the controller regulates operation of the exhaust cooling circuit and the compressor when the temperature data received from the signal is greater than the predetermined temperature as can be seen in row 1 of the below table (1) to enhance the overall efficiency of the heating ventilating and air conditioning system (200) in the vehicle (300). Further, the control unit (204) is configured to actuate the evaporator (202) selectively to cool the cabin air received from the exhaust heat exchanger (100), wherein the valve (205) is regulated to close to prevent heating of the cabin air in the exhaust heat exchanger (100). In such condition, the exhaust heat exchanger (100) receives and allows flow of the cabin air, while no heat exchange occurs between the cabin air and the exhaust gas. In the illustrative embodiment, the control unit (204) regulates operation of the compressor, evaporator (202) and the valve (205) for a predetermined period based on the determined condition corresponding to the determined difference to further enhance the efficiency of the heating ventilating and air conditioning system (200). In an embodiment, the vehicle (300) is a heavy commercial vehicle, not limited to a bus.
Table 1:

Set Cabin Temp Exhaust Cooling mode* Operational
Temp (C) cooling circuit* condition
18°C Above >=
27°C
>=(Tset+9) Yes Yes Both ON
18°C 23~27°C >=(Tset +5) & < (Tset+9) Yes Cyclic ON - OFF VCRS Cycle:
1. OFF for 10
minutes
2. ON for 5
minutes

18°C 21~23°C >=(Tset +3) & < (Tset+5) Yes Cyclic ON - OFF VCRS Cycle:
1.OFF for 20
minutes
2. ON for 5
minutes
18°C 19~21°C Cyclic ON - OFF TAC Cycle:
>=(Tset +1) & < (Tset+3) OFF 1. OFF for 30
minutes
2. ON for 5
minutes
18°C 17~19°C >=(tset - (1)1) & < (Tset+1) OFF OFF Both OFF.
Only Blower ON
18°C Below <17°C <(Tset-1) OFF OFF Heating mode ON
In an embodiment, the control unit (204) may be a centralised control unit of the vehicle (300) or may be a dedicated control unit to the system (200) associated with the centralised control unit of the vehicle (300). The control unit (204) may also be associated with other control units including, but not limited to, body control unit, engine control unit, transmission control unit, and the like. The control unit (204) may be comprised of a processing unit. The processing unit may comprise at least one data processor for executing program components for executing user- or system-generated requests. The processing unit may be a specialized processing unit such as integrated system controllers, memory management control units, floating point units, graphics processing units, digital signal processing units, etc. The processing unit may include a microprocessor, such as AMD Athlon, Duron or Opteron, ARM’s application, embedded or secure processors, IBM PowerPC, Intel’s Core, Itanium, Xeon, Celeron or other line of processors, etc. The processing unit may be implemented using a mainframe, distributed processor, multi-core, parallel, grid, or other architectures. Some embodiments may utilize embedded technologies like application-specific integrated circuits, digital signal processors, Field Programmable Gate Arrays, etc.

The control unit (204) may be disposed in communication with one or more memory devices via a storage interface. The storage interface may connect to memory devices including, without limitation, memory drives, removable disc drives, etc., employing connection protocols such as serial advanced technology attachment, integrated drive electronics, IEEE-1394, universal serial bus, fiber channel, small computing system interface, etc. The memory drives may further include a drum, magnetic disc drive, magneto-optical drive, optical drive, redundant array of independent discs, solid-state memory devices, solid-state drives, etc.
Referring now to Figure 4 which is an exemplary embodiment of the present disclosure illustrating a method (400) for operating a heating ventilating and air conditioning system (200).
The method (400) may describe in the general context of processor executable instructions in the control unit (204). Generally, the executable instructions may include routines, programs, objects, components, data structures, procedures, modules, and functions, which perform particular functions or implement particular abstract data types.
The order in which the method (400) is described is not intended to be construed as a limitation, and any number of the described method (400) blocks may be combined in any order to implement the method (400). Additionally, individual blocks may be deleted from the methods without departing from the scope of the subject matter described herein. Furthermore, the method (400) can be implemented in any suitable hardware, software, firmware, or combination thereof.
At block 401, the control unit (204) is configured to receive at least one signal from one or more sensors (203) corresponding to at least one cooling parameter associated with the cabin air. The sensors (203) may include temperature sensors, temperature and humidity sensors and the like. In the illustrative embodiment, the sensors (203) are depicted as temperature sensors to sense temperature in the cabin and transmit signal corresponding to temperature in the cabin of the vehicle (300). The control unit (204) is configured to receive the signal from the sensors (203) corresponding to at least one cooling parameter i.e., temperature of the cabin air.
At block 402, the control unit (204) determines a condition for heating the cabin air based on the temperature of the cabin air based on the signal received from the sensors (203). The control unit (204) compares the at least one cooling parameter from the signal transmitted by the

sensors (203) with a predetermined set of values corresponding to the cooling parameter to determine the condition for heating the cabin air. In an embodiment, the predetermined set of values may include a minimum temperature or minimum humidity, where heating of cabin air is required to provide optimal temperature within the cabin of the vehicle (300). Further, the control unit (204) is configured to compare the determined difference between the temperature and the predetermined temperature with a predetermined difference value to determine the condition for heating the cabin air. For example, as shown in below table 1, the control unit (204) determines the condition for heating the cabin air only when the determined difference is less than or equal to the predetermined difference or when the temperature from the signal is less than the predetermined temperature value.
At block 403, the control unit (204) may regulate the valve (205) to restrict the flow of the exhaust gas when the cooling parameter is above the predetermined set of value. For example, the control unit (204) may regulate the valve (205) to allow flow of the exhaust gas when the temperature of the cabin air is above the predetermined temperature value. The predetermined temperature value may include a minimum temperature, where heating of cabin air is required to provide optimal temperature within the cabin of the vehicle (300). The control unit (204) is configured to determine a difference in the cooling parameter received from the at least one signal with the predetermined set of values. For example, the control unit (204) is configured to determine a difference between the temperature received from the signal and the predetermined temperature value. In an embodiment, the control unit (204) is configured to regulate the exhaust cooling circuit, the compressor, and the valve (205) based on the determined condition. For example, the controller regulates operation of the exhaust cooling circuit and the compressor when temperature from the signal is greater than the predetermined temperature as can be seen in row 1 of the below table (1) to enhance the overall efficiency of the heating ventilating and air conditioning system (200) in the vehicle (300). Further, the control unit (204) is configured to actuate the evaporator (202) selectively to cool the cabin air received from the exhaust heat exchanger (100), wherein the valve (205) is regulated to close to prevent heating of the cabin air in the exhaust heat exchanger (100). In such condition, the exhaust heat exchanger (100) receives and allows flow of the cabin air, while no heat exchange occurs between the cabin air and the exhaust gas. In the illustrative embodiment, the control unit (204) regulates operation of the compressor, evaporator (202) and the valve (205) for a predetermined period based on the determined condition corresponding to the determined

difference to further enhance the efficiency of the heating ventilating and air conditioning system (200).
In an embodiment, the exhaust heat exchanger (100) utilizes heat from the exhaust gas of the vehicle (300) to heat the cabin air and thereby eliminates need for an external heating device or heating source to heat cabin air.
In an embodiment, the exhaust heat exchanger (100) reduces the expenses incurred for including external heating device or heating source to heat the cabin air.
In an embodiment, the conduits (3) of the exhaust heat exchanger (100) act as muffler to reduce noise due to flow of exhaust gas.
In an embodiment, the method (400) for operating the heating ventilating and air conditioning system (200) provides enhanced efficiency to cool and heat the cabin air, while reducing expenses incurred.
EQUIVALENTS
With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.
It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims are generally intended as “open” terms. It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an”; the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an

introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number. Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”
In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.
While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.
Referral Numeral:

Component Referral numeral
Exhaust heat exchanger 100
Housing 1
Plurality of fins 2
Plurality of conduits 3
Inlet 4
Outlet 5
Lateral axis AA’
System 200
Heat exchanger 201
Evaporator 202

One or more sensors 203
Control unit 204
Valve 205
Blower 206
Compressor 207
Low temperature Heater 208
Air vents 209
Recirculation grill 210
Exhaust valve 211
Vehicle 300
Exhaust cooling circuit 301
Method 400
Exhaust conduit 303

We claim:
1. An exhaust heat exchanger (100) for a heating ventilating and air conditioning system
(200) in a vehicle (300), the exhaust heat exchanger (100) comprising:
a housing (1) connectable to a portion of a vehicle body, the housing (1) is adapted to receive exhaust gas from an exhaust manifold of an engine of the vehicle (300); and
a plurality of fins (2) defined on the housing and extending downwardly away from the housing and exposed to cabin air wherein the plurality of fins (2) exchange heat with the cabin air to heat the cabin air of the vehicle (300).
2. The exhaust heat exchanger (100) as claimed in claim 1, wherein the housing (1) is configured with a plurality of conduits (3) on an inner surface along a lateral axis (AA’) to define at least one flow path in the housing (1).
3. The exhaust heat exchanger (100) as claimed in claim 2, wherein the housing (1) is defined with an inlet (4) at one end to receive the exhaust gas from the engine, wherein the housing (1) is defined with an outlet on another end to vent out the exhaust gas after heat exchange.
4. The exhaust heat exchanger (100) as claimed in claim 3, wherein the plurality of conduits (3) are configured to guide the exhaust gas from the inlet to the outlet in a controlled directional flow.
5. A heating ventilating and air conditioning system (200) for a vehicle (300), the system (200) comprising:
an exhaust heat exchanger (100) connectable to an exhaust manifold of an engine, the exhaust heat exchanger (100) comprising:
a housing (1) connectable to a portion of a vehicle body, the housing (1) is
adapted to receive exhaust gas from an exhaust manifold of an engine of the
vehicle (300); and
a plurality of fins (2) defined on the housing and extending downwardly
away from the housing and exposed to cabin air wherein the plurality of fins (2)
exchange heat with the cabin air to heat the cabin air of the vehicle (300);
a heat exchanger (201) fluidly coupled to the exhaust manifold of the vehicle (300) to receive and exchange heat with the exhaust gas of the vehicle (300);

an evaporator (202) fluidly coupled to a compressor to receive a refrigerant, the evaporator (202) is fluidly coupled to the exhaust heat exchanger (100) to selectively receive and cool the cabin air;
one or more sensors (203) disposable in the vehicle (300) configured to sense and transmit at least one signal corresponding to at least one cooling parameter associated with the cabin air;
a control unit (204) communicatively coupled to the evaporator (202) and the one or more sensors (203), wherein the control unit (204) is configured to:
receive the at least one signal from the one or more sensors (203); determine a condition for heating the cabin air; and
regulate a valve (205) connected between the exhaust manifold and the exhaust heat exchanger (100) to selectively allow the exhaust gas into the exhaust heat exchanger (100) to heat the cabin air.
6. The heating ventilating and air conditioning system (200) as claimed in claim 5, wherein the heating, ventilating, and air conditioning system (200) is an adsorption based cooling system (200).
7. A method (400) for operating a heating ventilating and air conditioning system (200) in a vehicle (300), the method (400) comprising:
receiving, by a control unit (204), at least one signal from one or more sensors (203) to at least one cooling parameter associated with the cabin air;
determining, by the control unit (204), a condition for heating the cabin air based on the at least one cooling parameter, and
regulating, by the control unit (204), a valve (205) connected between an exhaust manifold and an exhaust heat exchanger (100) to selectively allow exhaust gas into the exhaust heat exchanger (100) to heat the cabin air based on the comparison of the at least one cooling parameter.
8. The method (400) as claimed in claim 7, comprises:
determining, by the control unit (204), the condition for heating the cabin air based on comparing the at least one cooling parameter from the at least one signal transmitted by the one or more sensors (203) with a predetermined set of values corresponding to the at least one cooling parameter.

9. The method (400) as claimed in claim 7, comprises:
determining, by the control unit (204), difference in the at least one cooling parameter received from the at least one signal with the predetermined set of values; and
actuating, by the control unit (204), an evaporator (202) selectively to cool the cabin air received from the exhaust heat exchanger (100), wherein the valve (205) is regulated to close to prevent heating of the cabin air in the exhaust heat exchanger (100).
10. The method (400) as claimed in claim 9, comprises:
comparing, by the control unit (204), the determined difference between the at least one cooling parameter and the at least one signal with a predetermined difference value.