Combination radiator and condenser apparatus for motor vehicle

• US 5,080,167 A
• Filed: 02/01/1991
• Issued: 01/14/1992
• Est. Priority Date: 06/12/1990
• Status: Expired due to Fees

• Current Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Original Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Inventors: Wolf, Peter G.
• Primary Examiner(s): Tapolcai, William E.
• Application Number:
  US07/649,626
• Time in Patent Office: 347 Days
• Field of Search: 62/507, 62/239, 62/244, 165/140, 165/153, 165/164, 165/42, 165/43
• US Class Current: 165/140
• CPC Class Codes: B60H 1/3227 characterised by the arrangement or the type of heat exchanger, e.g. condenser, evaporator condensed liquid drainage means B60H1/3233
• CPC Class Codes: F25B 39/04 Condensers
• CPC Class Codes: F28D 1/0443 Combination of units extending one beside or one above the other F28D1/0452 takes precedence
• CPC Class Codes: F28D 1/05391 with multiple rows of conduits or with multi-channel conduits combined with a particular flow pattern, e.g. multi-row multi-stage radiators
• CPC Class Codes: F28D 2021/0084 Condensers
• CPC Class Codes: F28D 2021/0094 for recooling the engine coolant arrangements of liquid-to-air heat exchangers on vehicles F01P3/18
• CPC Class Codes: F28F 1/022 with multiple channels
• CPC Class Codes: F28F 2210/04 Arrangements of conduits common to different heat exchange sections, the conduits having channels for different circuits

Abstract

A combination radiator and condenser apparatus for a motor vehicle has inlets and outlets adapted to be connected in both a coolant system for a liquid cooled engine and in a refrigerant system of an automobile air conditioning system. The apparatus includes a plurality of axially aligned fluid flow tubes having the same air centers and the tubes each extend between combination radiator and condenser tanks, in one embodiment the axially aligned fluid flow tubes are unitary, integral fluid flow tubes with a separate refrigerant vapor passage and a separate engine coolant passage therein. A method for simultaneously cooling engine coolant and refrigerant vapor in combined radiator and condenser apparatus for a motor vehicle includes the steps directing vehicle inlet airstream through common air centers between the axially aligned refrigerant vapor tubes and vehicle coolant tubes.

Claims

1. A combination radiator and condenser apparatus for a motor vehicle having a plurality of parallel tube passes for cooling high pressure refrigerant vapor in an air conditioning system for the motor vehicle and for cooling engine coolant having air centers bonded thereto for cooling fluid flow through said parallel tube passes by directing the inlet airstream of a motor vehicle therethrough comprising:

said parallel tube passes each including a flow tube with aligned tube segments forming a refrigerant flow path and a separate coolant flow path;

pairs of said parallel tube passes having a gap therebetween;

first header means communicating with said coolant flow paths for flow of coolant therethrough;

second header means for communicating said refrigerant flow paths with a mechanical refrigerant system for directing refrigerant vapor through said refrigerant flow paths for condensation therein;

an air center element in each of said gaps between each of said pairs of said parallel tube passes in common heat transfer contact with both said refrigerant flow path and said coolant flow path;

each air center element having a plurality of spaced parallel uninterrupted axial air passages therethrough in axial alignment with the inlet airstream for directing the inlet airstream initially only across the refrigerant flow path followed by flow of the inlet airstream only across the coolant flow path; and

means bonding said air center element to said refrigerant flow path and said coolant flow path for conductively extracting heat simultaneously from the refrigerant flow path and from the coolant flow path into the air center for removal therefrom by flow of said inlet airstream through said uninterrupted axial air passages.

2. A combination radiator and condenser apparatus for a motor vehicle having a plurality of parallel tube passes for cooling high pressure refrigerant vapor in an air conditioning system for the motor vehicle and for cooling engine coolant having air centers bonded thereto for cooling fluid flow through said parallel tube passes by directing the inlet airstream of a motor vehicle therethrough comprising:

said parallel tube passes each including a flow tube with aligned tube segments forming a refrigerant flow path and a separate coolant flow path;

pairs of said parallel tube passes having a gap therebetween;

first header means communicating with said coolant flow paths for flow of coolant therethrough;

second header means for communicating said refrigerant flow paths with a mechanical refrigerant system for directing refrigerant vapor through said refrigerant flow paths for condensation therein; and

an air center element in each of said gaps between each of said pairs of said parallel tube passes in common heat transfer contact with both said refrigerant flow path and said coolant flow path;

each air center element having a plurality of spaced parallel uninterrupted axial air passages therethrough in axial alignment with the inlet airstream for directing the inlet airstream initially only across the refrigerant flow path followed by flow of the inlet airstream only across the coolant flow path; and

means bonding said air center element to said refrigerant flow path and said coolant flow path for conductively extracting heat simultaneously from the refrigerant flow path and from the coolant flow path into the air center for removal therefrom by flow of said inlet airstream through said uninterrupted axial air passages;

each of said flow tubes being a unitary tube having a divider separating said unitary tube into said coolant flow path and said refrigerant flow path.

3. A combination radiator and condenser apparatus for a motor vehicle having a plurality of parallel tube passes for cooling high pressure refrigerant vapor in an air conditioning system for the motor vehicle and for cooling engine coolant having air centers bonded thereto for cooling fluid flow through said parallel tube passes by directing the inlet airstream of a motor vehicle therethrough comprising:

said parallel tube passes each including a flow tube with aligned tube segments forming a refrigerant flow path and a separate coolant flow path;

pairs of said parallel tube passes having a gap therebetween;

first header means communicating with said coolant flow paths for flow of coolant therethrough;

second header means for communicating said refrigerant flow paths with a mechanical refrigerant system for directing refrigerant vapor through said refrigerant flow paths for condensation therein; and

an air center element in each of said gaps between each of said pairs of said parallel tube passes in common heat transfer contact with both said refrigerant flow path and said coolant flow path;

each air center element having a plurality of spaced parallel uninterrupted axial air passages therethrough in axial alignment with the inlet airstream for directing the inlet airstream initially only across the refrigerant flow path followed by flow of the inlet airstream only across the coolant flow path; and

means bonding said air center element to said refrigerant flow path and said coolant path for conductively extracting heat simultaneously from the refrigerant flow path and from the coolant flow path into the air center for removal therefrom by flow of said inlet airstream through said uninterrupted axial air passages;

each of said flow tubes being an extruded unitary tube with an integral divider web separating said unitary tube into said coolant flow path and said refrigerant flow path.

4. A combination radiator and condenser apparatus for a motor vehicle having a plurality of parallel tube passes for cooling high pressure refrigerant vapor in an air conditioning system for the motor vehicle and for cooling engine coolant having air centers bonded thereto for cooling fluid flow through said parallel tube passes comprising:

said parallel tube passes each including a flow tube with aligned segments forming a refrigerant passage and a separate coolant passage;

first header means communicating with said coolant passages for flow of coolant therethrough;

second header means for communicating said refrigerant passages with a mechanical refrigerant system for directing refrigerant vapor through said refrigerant passages for condensation therein;

a single air center commonly connected to each of said aligned flow tube segments for conductively transferring heat from said coolant and said refrigerant vapor;

said parallel tube passes having a notched end including an extension portion with an inlet opening therein;

a radiator header plate;

said extension portion extending through said radiator header plate for directing coolant from said radiator tank to said coolant passages for flow therethrough in heat transfer relationship with air flow across said air centers;

a second radiator header plate located in sealed spaced relationship to said first radiator header plate to form a fluidly sealed space therebetween;

a stepped surface on said notched end having a refrigerant vapor inlet formed therein in communication with said fluidly sealed space for directing vapor therefrom into said refrigerant passages; and

means for directing refrigerant vapor into said fluidly sealed space for flow therefrom through said refrigerant vapor inlets and said refrigerant passages for condensing refrigerant in said refrigerant passages in response to air flow across said air centers.

5. A combination radiator and condenser apparatus for removing heat from coolant in a liquid cooled engine and from high pressure refrigerant vapor in a mechanical refrigerant system by directing the inlet airstream of a motor vehicle therethrough comprising:

a plurality of flow tubes;

each of said flow tubes having a divider member therein and opposite opened ends and each of said flow tubes having a liquid coolant passage therein and a refrigerant vapor passage therein extending between said opposite ends;

said divider member separating said liquid coolant passage from said refrigerant passage so as to prevent mixing of fluid between said coolant passage and said refrigerant vapor passage;

header means at each end of said plurality of flow tubes for directing liquid coolant from said engine to said liquid coolant passages and for directing refrigerant vapor from said mechanical refrigeration system through said refrigerant vapor passages for condensation in said refrigerant vapor passages; and

an air center element engaging said plurality of flow tubes and having a plurality of spaced parallel uninterrupted axial air passages for directing the inlet airstream initially only across the refrigerant vapor passage followed by uninterrupted flow of the inlet airstream across the liquid coolant passage; and

means bonding said air center element to said refrigerant vapor passage and said liquid coolant passage for conductively extracting heat simultaneously from the refrigerant vapor passage and from the coolant passage into the air center for removal therefrom by flow of said inlet airstream through said uninterrupted axial air passages.

6. A combination radiator and condenser apparatus for removing heat from coolant in a liquid cooled engine and from high pressure refrigerant vapor in a mechanical refrigerant system by directing the inlet airstream of a motor vehicle therethrough comprising:

a plurality of flow tubes;

each of said flow tubes having a divider member therein and opposite opened ends and each of said flow tubes having a liquid coolant passage therein and a refrigerant vapor passage therein extending between said opposite ends;

said divider member separating said liquid coolant passage from said refrigerant passage so as to prevent mixing of fluid between said coolant passage and said refrigerant vapor passage;

header means at each end of said plurality of flow tubes for directing liquid coolant from said engine to said liquid coolant passages and for directing refrigerant vapor from said mechanical refrigeration system through said refrigerant vapor passages for condensation in said refrigerant vapor passages; and

an air center element engaging said plurality of flow tubes and having a plurality of spaced parallel uninterrupted axial air passages for directing the inlet airstream initially only across the refrigerant vapor passage followed by uninterrupted flow of the inlet airstream across the liquid coolant passage; and

means bonding said air center element to said refrigerant vapor passage and said liquid coolant passage for conductively extracting heat simultaneously from the refrigerant vapor passage and from the coolant passage into the air center for removal therefrom by flow of said inlet airstream through said uninterrupted axial air passages;

each of said flow tubes being a unitary tube having a divider separating said unitary tube into said coolant passage and said refrigerant passage.

7. A combination radiator and condenser apparatus for removing heat from coolant in a liquid cooled engine and from high pressure refrigerant vapor in a mechanical refrigerant system by directing the inlet airstream of a motor vehicle therethrough comprising:

a plurality of flow tubes;

each of said flow tubes having a divider member therein and opposite opened ends and each of said flow tubes having a liquid coolant passage therein and a refrigerant vapor passage therein extending between said opposite ends;

said divider member separating said liquid coolant passage from said refrigerant passage so as to prevent mixing of fluid between said coolant passage and said refrigerant vapor passage;

header means at each end of said plurality of flow tubes for directing liquid coolant from said engine to said liquid coolant passages and for directing refrigerant vapor from said mechanical refrigeration system through said refrigerant vapor passages for condensation in said refrigerant vapor passages; and

an air center element engaging said plurality of flow tubes and having a plurality of spaced parallel uninterrupted axial air passages for directing the inlet airstream initially only across the refrigerant vapor passage followed by uninterrupted flow of the inlet airstream across the liquid coolant passage; and

means bonding said air center element to said refrigerant vapor passage and said liquid coolant passage for conductively extracting heat simultaneously from the refrigerant vapor passage and from the coolant passage into the air center for removal therefrom by flow of said inlet airstream through said uninterrupted axial air passages;

each of said flow tubes being an extruded unitary tube with an integral divider web separating said extruded unitary tube into said coolant passage and said refrigerant passage.

8. A combination radiator and condenser apparatus for removing heat from a coolant in a liquid cooled engine and from high pressure refrigerant vapor in a mechanical refrigerant system comprising:

a plurality of flow tubes;

each of said flow tubes having a divider member therein and opposite opened ends and each of said flow tubes having a liquid coolant passage therein and a refrigerant vapor passage therein extending between said opposite ends;

said divider member separating said liquid coolant passage from said refrigerant passage so as to prevent mixing of fluid between said coolant passage and said refrigerant vapor passage;

header means at each end of said plurality of flow tubes for directing liquid coolant from said engine to said liquid coolant passages and for directing refrigerant vapor from said mechanical refrigeration system through said second passages for condensation in said refrigerant passage;

common air center means for directing air across said plurality of flow tubes for removing energy from said liquid coolant and from said refrigerant vapor prior to return thereof respectively to said liquid cooled engine and said mechanical refrigeration system; and

said header means including first header means and second header means;

said first header means including a coolant inlet tank, said second header means including a fitting connected to said coolant tank and including means for directing refrigerant vapor into each of said refrigerant vapor passages.

9. A combination radiator and condenser apparatus for a motor vehicle having a plurality of parallel tube passes for cooling high pressure refrigerant vapor in an air conditioning system for the motor vehicle and for cooling engine coolant having air centers bonded thereto for cooling fluid flow through said parallel tube passes comprising:

said parallel tube passes each including a flow tube with aligned segments forming a refrigerant passage and a separate coolant passage;

first header means communicating with said coolant passages for flow of coolant therethrough;

second header means for communicating said refrigerant passages with a mechanical refrigerant system for directing refrigerant vapor through said refrigerant passages for condensation therein;

a single air center commonly connected to each of said aligned flow tube segments for conductively transferring heat from said coolant and said refrigerant vapor;

said parallel tube passes having a notched end including an extension portion with an inlet opening therein;

a radiator header plate;

said extension portion extending through said radiator header plate for directing coolant from said radiator tank to said coolant passages for flow therethrough in heat transfer relationship with air flow across said air centers;

a second radiator header plate located in sealed spaced relationship to said first radiator header plate to form a fluidly sealed space therebetween;

a stepped surface on said notched end having a refrigerant vapor inlet formed therein in communication with said fluidly sealed space for directing vapor therefrom into said refrigerant passages;

means for directing refrigerant vapor into said fluidly sealed space for flow therefrom through said refrigerant vapor inlets and said refrigerant passages for condensing refrigerant in said refrigerant passages in response to air flow across said air centers;

means for connecting said notched ends to said first radiator header plate to seal said notched ends to said first radiator header plate; and

said notched ends each having a surface portion thereon extending through said second radiator head plate; and

means for sealing said surface portion to said second radiator header plate to prevent leakage from said fluidly sealed space while fixedly locating said refrigerant vapor inlets in said sealed fluid space.

10. A unitary combination radiator and condenser assembly for a motor vehicle comprising:

a radiator coolant tank including a first header plate;

a second header plate having first portions thereon sealed to said first header plate and second portions thereon spaced from said first header plate to define a fluidly sealed gas space therebetween fluidly sealed from said radiator coolant tank;

a plurality of parallel unitary tubes each having first and second passages for respective flow of coolant and refrigerant;

each of said unitary tubes further having a tube end connected to said first header plate and extending therethrough in sealed relationship therewith into said radiator coolant tank;

means forming an opening in said tube end communicating said radiator coolant tank with said first passage;

an end on each of said unitary tubes extending through said second header plate;

said end having a refrigerant vapor inlet therein communicating with said second passage;

each of said unitary tubes extending through said second header plate and sealed relative thereto and in communication with said fluidly sealed gas space at said refrigerant vapor inlet for directing refrigerant vapor from said gas space for flow through said refrigerant inlet and said second passage.

11. In the unitary combination radiator and condenser assembly of claim 10,

pairs of said unitary tubes having a gap therebetween for flow of the inlet airstream of the motor vehicle;

a common air center located in said gap and bonded to each of said pairs of unitary tubes for conductive heat transfer of heat from coolant flow in said first passages and refrigerant flow in said second passages therein.

12. In the unitary combination radiator and condenser assembly of claim 10, each of said unitary tube passes having an integral divider web between said first and second passages.

13. In the unitary combination radiator and condenser assembly of claim 10, each of said unitary tube passes being an extruded tube having an integral divider web therein forming said first and second passages.

14. In the unitary combination radiator and condenser assembly of claim 10,

pairs of said unitary tubes having a gap therebetween for flow of the inlet airstream of the motor vehicle;

a common air center located in said gap and bonded to each of said pairs of unitary tubes for conductive heat transfer of heat from said coolant flow in said first passages and refrigerant flow in said second passages therein.

each of said unitary tube passes having an integral divider web between said first and second passages.

15. In the unitary combination radiator and condenser assembly of claim 10,

pairs of said unitary tubes having a gap therebetween for flow of the inlet airstream of the motor vehicle;

a common air center located in said gap and bonded to each of said pairs of unitary tubes for conductive heat transfer of heat from said coolant flow in said first passages and flow of refrigerant in said second passages therein;

each of said unitary tube passes being an extruded tube having an integral divider web therein forming said first and second passages.

16. A flow device for use in a combination radiator and condenser apparatus for a motor vehicle comprising:

tube means with a leading air flow edge and a trailing air flow edge;

aligned segments on said tube means forming a refrigerant vapor passage adjacent said leading air flow end and a coolant passage adjacent said trailing air flow end;

means forming side surface on said aligned segments adapted to be bonded to a common air center for simultaneous conductive heat transfer from refrigerant and coolant passing through said tube means;

an extension on the end of said tube means forming an inlet to said coolant passage;

a notch on said extension of said tube means forming an inlet to said refrigerant vapor passage.

17. In the flow device of claim 16,

said tube means being a unitary member formed as tubular extrusion having a divider web.

18. In the flow device of claim 16,

said tube means being a tubular extrusion having a generally oval cross-section with a rounded leading airflow inlet end and a rounded trailing airflow end.

19. In the flow device of claim 17,

said tubular extrusion having a notch therein formed in part by a segment of said divider web.

20. An automotive air conditioning refrigerant system comprising:

combination radiator and condenser apparatus for cooling engine coolant and refrigerant vapor;

said apparatus including a plurality of tube passes each having a refrigerant vapor and a coolant flow passage therethrough;

means for directing coolant through said coolant flow passages;

means for directing refrigerant vapor through said refrigerant vapor fluid flow passages for condensing refrigerant gas therein as coolant is directed through said coolant flow passages;

an air center common to each of said tube passes tubes having the inlet air stream of the vehicle directed therethrough;

said air center removing heat from refrigerant vapor and coolant flows by conductive heat transfer from said plurality of tube passes; and

a plurality of baffles for passing said refrigerant in multiple passes through said second passages.

21. A combination radiator and condenser apparatus for a motor vehicle having a plurality of parallel tube passes for cooling high pressure refrigerant vapor in an air conditioning system for the motor vehicle and for cooling engine coolant having air centers bonded thereto for cooling fluid flow through said parallel tube passes comprising:

said parallel tube passes each including aligned segments forming a refrigerant passage and a separate coolant passage;

first header means communicating with said coolant passages for flow of coolant therethrough;

second header means for communicating said refrigerant passages with a mechanical refrigerant system for directing refrigerant vapor through said refrigerant passages for condensation therein;

a single air center commonly connected to each of said aligned segments for conductively transferring heat from said coolant and said refrigerant vapor; and

a plurality of baffles for passing said refrigerant vapor in multiple passes through said refrigerant passages.

22. In the unitary combination radiator and condenser assembly of claim 21,

a plurality of baffles for passing said refrigerant vapor in multiple passes through said refrigerant passages.

23. A combination radiator and condenser apparatus for a motor vehicle having a plurality of parallel tube passes for cooling high pressure refrigerant vapor in an air conditioning system for the motor vehicle and for cooling engine coolant having air centers bonded thereto for cooling fluid flow through said parallel tube passes comprising:

said parallel tube passes each including aligned segments forming a refrigerant passage and a separate coolant passage;

first header means communicating with said coolant passages for flow of coolant therethrough;

second header means for communicating said refrigerant passages with a mechanical refrigerant system for directing refrigerant vapor through said refrigerant passages for condensation therein;

a single air center commonly connected to each of said aligned flow tube segments for conductively transferring heat from said coolant and said refrigerant vapor; and

each of said tube passes being extruded tubes having opposite notched ends forming end openings to said refrigerant vapor passage.

24. A combination radiator and condenser apparatus for a motor vehicle having spaced parallel tube passes with air flow centers bonded therebetween for removing heat from a liquid cooled engine and a mechanical refrigerant system characterized by:

each of said parallel tube passes formed as an extruded tube;

each of said extruded tubes having opposite ends and each of said extruded tubes having an integral divider web separating said extruded tube into first and second passages for flow of coolant and refrigerant vapor, respectively;

a single header at each end of said plurality of extruded tubes including first flow direct or means forming a space for liquid coolant and means on each of said tubes for directing liquid coolant from said space for flow of liquid coolant to said first passages;

second flow director means on said single header for directing refrigerant vapor from a mechanical refrigerant system through said second passages for condensation therein; and

means for directing air across said plurality of extruded tubes for removing heat from said liquid coolant and from said refrigerant vapor prior to return thereof respectively to said liquid cooled engine and said mechanical refrigerant system.

25. A combination radiator and condenser apparatus for a motor vehicle having spaced parallel tube passes with air flow centers bonded therebetween for removing heat from a liquid cooled engine and a mechanical refrigerant system characterized by:

each of said parallel passes formed as an extruded tube;

each of said extruded tubes having opposite ends and each of said extruded tubes having an integral divider web separating said extruded tube into first and second passages for flow of coolant and refrigerant vapor, respectively;

header means at each end of said plurality of extruded tubes including first flow directing means including a space for liquid coolant and means on each of said tubes for directing liquid coolant from said space for liquid coolant to said first passages;

second flow director means for directing refrigerant vapor from a mechanical refrigerant system through said second passages for condensation in said refrigerant passage;

means for directing air across said plurality of extruded tubes for removing heat from said liquid coolant and from said refrigerant gas prior to return thereof respectively to said liquid cooled engine and said mechanical refrigerant system; and

said second flow director means including a refrigerant vapor space and a notched portion on the end of each of said extruded tubes forming an inlet in communication with said refrigerant vapor space.

26. A combination radiator and condenser apparatus for a motor vehicle having spaced parallel tube passes with air flow centers bonded therebetween for removing heat from a liquid cooled engine and a mechanical refrigerant system characterized by:

each of said parallel passes formed as an extruded tube;

each of said extruded tubes having opposite ends and each of said extruded tubes having an integral divider web separating said extruded tube into first and second passages for flow of coolant and refrigerant vapor, respectively;

header means at each end of said plurality of extruded tubes including first flow directing means including a space for liquid coolant and means on each of said tubes for directing liquid coolant from said space for liquid coolant to said first passages;

second flow director means for directing refrigerant vapor from a mechanical refrigerant system through said second passages for condensation in said refrigerant passage;

means for directing air across said plurality of extruded tubes for removing heat from said liquid coolant and from said refrigerant vapor prior to return thereof respectively to said liquid cooled engine and said mechanical refrigerant system;

each of said extruded tubes having extensions thereon forming said end openings to said first passages;

said header means including a first plate bonded to said extensions at the outer surface thereof;

said first plate having a central portion and bent edge portions on each side of said central portion spaced with respect to said central portion;

a second plate joined to said bent edge portions for forming a refrigerant vapor space on one side of said first plate;

a tank member joined to said bent edge portions for forming a coolant space on the other side of said first plate;

said extension sealingly connected to said first plate for directing coolant from said coolant space into said coolant passages.

27. A combination radiator and condenser apparatus for a motor vehicle for removing heat from coolant in a liquid cooled engine and from high pressure refrigerant vapor in a mechanical refrigerant system comprising:

a plurality of unitary tubes;

each of said unitary tubes having opposite opened ends and each of said unitary tubes having a liquid coolant passage therein and a refrigerant vapor passages therein extending between said opposite ends;

each of said unitary tubes having divider means separating said liquid coolant passage from said refrigerant passage;

header means at each end of said plurality of unitary tubes for directing liquid coolant from said engine to said liquid coolant passages and for directing refrigerant vapor from said mechanical refrigerant system through said refrigerant vapor passages for condensation in said refrigerant vapor passages;

common air center means for directing air across said plurality of unitary tubes for moving energy from said liquid coolant and from said refrigerant gas prior to return thereof respectively to said liquid cooled engine and said mechanical refrigerant system; and

each of said unitary tubes having opposite notched ends forming openings to said refrigerant vapor passage.

28. A combination radiator and condenser apparatus for a motor vehicle for removing heat from coolant in a liquid cooled engine and from high pressure refrigerant vapor in a mechanical refrigerant system comprising:

a plurality of unitary tubes;

each of said unitary tubes having opposite opened ends and each of said unitary tubes having a liquid coolant passage therein and a refrigerant vapor passages therein extending between said opposite ends;

each of said unitary tubes having divider means separating said liquid coolant passage from said refrigerant passage;

header means at each end of said plurality of unitary tubes for directing liquid coolant from said engine to said liquid coolant passages and for directing refrigerant vapor from said mechanical refrigerant system through said refrigerant vapor passages for condensation in said refrigerant vapor passages;

common air center means for directing air across said plurality of unitary tubes for moving energy from said liquid coolant and from said refrigerant gas prior to return thereof respectively to said liquid cooled engine and said mechanical refrigerant system; and

each of said unitary tubes having opposite extensions thereon forming openings to said refrigerant vapor passage; and

said header means including a first plate having a central portion and bent edge portions on each side of said central portion spaced with respect to said central portion;

a second plate joined to said bent edge portions for forming a first header space on one side of said first plate and a tank member joined to said bent edge portions for forming a second header space on the other side of said first plate;

said opposite extensions sealingly connected to said first plate for directing coolant from said second header space into said coolant passages; and

means for directing refrigerant vapor from said first header space into said refrigerant vapor passages.