Heat exchanger for stationary air conditioning system with improved water condensate drainage

Abstract

A heat exchanger in a cabinet space for use in a stationary air conditioning system, wherein the heat exchanger has a pair of substantially horizontal manifold tanks engaged to a plurality of substantially vertically oriented flow tubes bent into substantially an L shape having a bend angle sufficiently steep that condensate runs along the surface under the force of gravity. Furthermore, the heat exchanger has improved fins and is angled in the horizontal direction for less inhibited drainage of condensate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a drawing of a prior art expanded tube and plate fin heat exchanger core typically used in an outdoor cabinet of the type having a generally rectangular prism shape;

FIG. 2 is a partially schematic view of a preferred embodiment of a heat exchanger according to the invention installed in a similar cabinet;

FIG. 3 is a side view of the heat exchanger showing the outlines of the cabinet;

FIG. 4 is a side view of a single tube showing the surface condensation water flow direction;

FIG. 5 is an enlarged plan view of a pair of tubes and air fin corrugations;

FIG. 6 is a detail of a portion of the surface of the bent section of a tube, showing the water flow in relation of the corrugated fin brazed to the tube surface;

FIG. 7 is a front view of the heat exchanger that illustrates adds a small horizontal tilt on the bottom tank.

Claims

1. A heat exchanger for use in a stationary air conditioning system having a heat exchanger cabinet space in substantially the shape of a rectangular prism with a predetermined height, a predetermined depth, a substantially vertical front grill area, and an air fan spaced horizontally from said front grill area, and in which air conditioning system a refrigerant heat exchanger contained in said cabinet space is subject to surface condensation from air passing thereover, said heat exchanger comprising, a pair of substantially horizontal and straight manifold tanks, one near the top of said cabinet space and one near the bottom, both of which are oriented substantially horizontally,and a plurality of substantially vertically oriented and parallel refrigerant flow tubes running from said top to said bottom tank, each tube being bent into substantially an L shape with a substantially vertically oriented straight section oriented substantially parallel to said front grill, and a substantially bent section having a bend angle from the horizontal that is sufficiently shallow that the vertical projection of said bent section fits within said predetermined height and depth and sufficiently steep that water condensed on said bent section runs along the surface thereof and under the force of gravity so as to drain therefrom.

2. A heat exchanger as recited in claim 1 further comprising: corrugated fins conjoining said flow tubes, wherein said fins have fin crests brazed to said flow tubes and means to provide condensate drainage through said brazed fin crests.

3. A heat exchanger as recited in claim 2 wherein said means to provide condensate drainage through said brazed fin crests include elongated louvers constructed in said fins, wherein said louvers form a pattern of angled lead louvers and angled trailing louvers.

4. A heat exchanger as recited in claim 3 wherein said fins are oriented so that said lead louvers are in the same general direction as the natural direction of condensate flow for less inhibited condensate drainage through said louvers.

5. A heat exchanger as recited in claim 1 wherein said heat exchanger is positioned between said fan and said front grill, and below said fan.

6. A heat exchanger as recited in claim 1 wherein said bent angle of said flow tube is about or greater than 10 degrees relative to the horizontal.

7. A heat exchanger as recited in claim 1 wherein said manifold tank near bottom of said cabinet is angled at about 5 degrees or greater relative to the horizontal.

8. A heat exchanger as recited in claim 1 where in said heat exchange is formed of brazed aluminum.

9. A heat exchanger as recited in claim 1 wherein said manifold tanks comprise of: a thick gauge aluminum base; anda clad aluminum slotted plate, wherein said slotted plate is brazed onto said aluminum base.

10. A heat exchanger for an air conditioning system with improved condensate drainage comprising of: a plurality of vertically oriented parallel refrigerant flow tubes having opposing tube end openings;top and bottom manifold tanks, wherein said tanks are substantially horizontal and hydraulically engaged with said respective tube end openings; andfins conjoining said flow tubes, wherein said fins have elongated louvers for directing condensate drainage;wherein said flow tubes are bent into substantially an L shape having a longer bent section and shorter bent section.

11. A heat exchanger as recited in claim 10 wherein said shorter bent section is located near said top manifold tank.

12. A heat exchanger as recited in claim 10 wherein said shorter bent section is located near said bottom manifold tank.

13. A heat exchanger as recited in claim 10 wherein said heat exchanger is angled at about 5 degrees or greater relative to the horizontal.

14. A heat exchanger of claim 10 wherein said substantially vertical flow tubes are bent about 10 degrees or greater relative to the horizontal.

15. A heat exchanger as recited in claim 10 wherein said elongated louvers form a pattern of angled lead louvers and angled trailing louvers, wherein that said lead louvers are oriented in the same general direction as the natural direction of condensate flow.

16. A heat exchanger for use in an air conditioning system positioned within a vented cabinet, said heat exchanger comprising, a pair of substantially horizontal manifold tanks, one near the top of said cabinet and one near the bottom;and a plurality substantially vertically oriented and parallel flow tubes running from said top to said bottom tank, each tube being bent into substantially an L shape with a longer, substantially vertically oriented straight section, and a substantially shorter bent section having a bend angle from the horizontal that is sufficiently shallow so that water condensed on said bent section runs along the surface thereof and under the force of gravity so as to drain therefrom.

17. A heat exchanger as recited in claim 16 wherein said bottom manifold tank is angled at about 5 degrees or greater relative to the horizontal.

18. A heat exchanger as recited in claim 17 wherein said bent angle of said tube is equal to or greater than 10 degrees relative to the horizontal.

19. A heat exchanger as recited in claim 18, further comprising fins conjoining said flow tubes, wherein said fins have elongated louvers for directing condensate drainage.

20. A heat exchanger as recited in claim 19 wherein said elongated louvers form a pattern of angled lead louvers and angled trailing louvers, wherein that said lead louvers are oriented in the same general direction as the natural direction of condensate flow.

21. A heat exchanger for use in a stationary air conditioning system having a heat exchanger cabinet space in substantially the shape of a rectangular prism with a predetermined height, a predetermined depth, a grill area, and an air fan spaced from said grill area, and in which air conditioning system a heat exchanger contained in said cabinet space is subject to surface condensation from air passing thereover, said heat exchanger comprising, a pair of substantially horizontal and straight manifold tanks, one near the top of said cabinet space and one near the bottom, both of which are oriented substantially horizontally,and a plurality of substantially vertically oriented and parallel flow tubes running from said top tank to said bottom tank, each tube being bent into substantially an L shape with a substantially vertically oriented straight section, and a substantially bent section having a bend angle from the horizontal that is sufficiently shallow that the vertical projection of said bent section fits within said predetermined height and depth and sufficiently steep that water condensed on said bent section runs along the surface thereof and under the force of gravity so as to drain therefrom.