EP2122266A1

EP2122266A1 - Condensate removal system

Info

Publication number: EP2122266A1
Application number: EP07700474A
Authority: EP
Inventors: Fabio Beretta; Maurizio Rabito; Laura Marcucci; Felice Pirovano
Original assignee: Carrier Corp
Current assignee: Carrier Corp
Priority date: 2007-01-10
Filing date: 2007-01-10
Publication date: 2009-11-25
Also published as: WO2008084277A1; CN101631995A

Abstract

A system and a method for condensate removal from a base pan of a condensing unit are provided. The condensate-removal system includes a condensate-collecting surface, a knock-out drain hole and a knock-out cover that is configured to fit in the knock-out drain hole. The knock-out cover, with protrusions extending from its perimeter, is cut out from the condensate-collecting surface of the base pan. The knock-out drain hole thus formed is then sealed by attaching the knock-out cover to it.

Description

CONDENSATE REMOVAL SYSTEM

FIELD OF THE INVENTION

The invention relates generally to the field of refrigeration systems, and more specifically, to condensate disposal arrangements used in refrigeration systems.

BACKGROUND OF THE INVENTION

In modern times, refrigeration systems have been widely used for consumer as well as industrial and commercial purposes. An air conditioner is a type of refrigeration system, which typically facilitates heating, ventilation and air-cooling. In split-type air conditioners, a separate outdoor condensing unit and an indoor evaporating unit are provided. When the air conditioner is operated in the heating mode, the operation of the air conditioner is reversed. Therefore, when the atmospheric temperature drops, water vapor in the air condenses on the condenser coil situated inside the condensing unit. This water gradually drips on the base pan of the condensing unit. In places where the atmospheric temperature is below the freezing point of water, the condensate freezes to form ice. Excessive ice formation may block the operation of . the propeller fan situated inside the condensing unit, and may impair the working of the system. The condensate, therefore, needs to be removed from the base pan of the condensing unit. Various arrangements have been provided to address the problem of condensate removal from the base pan. One such method involves the provision of a pump driven by a propeller fan motor to throw out the collected condensate. However, such pumps entail a high initial and maintenance cost, design complications, and the problem of wear and tear over a period of time. The increased weight of the condensing unit and difficulty in implementation are two more disadvantages in this instance.

Another method involves the provision of a drain pipe that is connected to the conventional drain hole. This drain pipe facilitates the process of draining out of the condensate continuously. However, in extreme cold conditions, ice is formed in the base pan, which may result in blockage of the drain pipe.

Yet another method involves the provision of knock-out drain holes to drain out the condensate. However, such knock-out drain holes are not sealed. As a result, water from the condenser coil continuously drips out from the condensing unit through the knock-out drain holes. To address this problem, rubber or silicon caps are used to seal the knock-out drain holes. This provision of caps, however, entails a high manufacturing cost.

In light of the foregoing discussion, there is a need for a condensate removal system that overcomes the problems stated above. In addition, the system is cost effective, simple in design and easy to implement. Further, the system aids in eliminating the problem of the condensate dripping through the knock-out drain holes. Moreover, the system should work even when there is ice formation on the base pan at extremely low temperatures.

SUMMARY

Embodiments of the invention provide a condensate-removal system in a condensing unit. The condensing unit includes a condenser coil, a propeller fan and a base pan. The condensate removal system includes a condensate-collecting surface, a knock-out drain hole, and a knock-out cover configured to fit in the knock-out drain hole. The knock-out cover has protrusions extending from its perimeter. These protrusions help in removably attaching the knock-out cover to a knock-out drain hole.

Further, embodiments of the invention provide an air-conditioning system that includes an evaporator unit, a condensing unit and a base pan with sealed knock-out drain holes. The condensing unit includes a condenser coil, a propeller fan and a base pan. The condensate removal system includes a condensate-collecting surface, a knock-out drain hole, and a knock-out cover that is configured to fit in the knock-out drain hole. The knock-out cover has a plurality of protrusions extending from its perimeter. The protrusions help in removably attaching the knock-out cover to the knockout drain hole.

Embodiments of the invention provide a method for manufacturing a base pan for a condensing unit of an air conditioning system. A knock-out cover, with a plurality of protrusions extending from its perimeter, is cut out from a condensate-collecting surface of the base pan. The knock-out drain hole that is formed after the knock-out cover is removed is then sealed by covering the knock-out hole with the knock-out cover again. The protrusions provided on the perimeter of the knock-out cover ensure that the cover is sealed.

BRIEF DESCRIPTION OF THE DRAWINGS

The preferred embodiments of the invention will hereinafter be described in conjunction with the appended drawings, provided to illustrate and not to limit the invention, wherein like designations denote like elements, and in which: Fig. 1 illustrates an environment in which the invention may be practiced, in accordance with an embodiment of the invention;

Fig. 2 illustrates various components of a condensing unit, in accordance with an embodiment of the invention;

Fig. 3 illustrates various components of a base pan of a condensing unit, in accordance with an embodiment of the invention;

Fig. 4 illustrates formation of sealed knock-out drain holes in a condensing unit, in accordance with an embodiment of the invention;

Fig. 5 illustrates the dimensions of a knock-out cover of a base pan of a condensing unit, in accordance with an embodiment of the invention; and

Fig. 6 is a flowchart illustrating a method for manufacturing the base pan of a condensing unit, in accordance with an embodiment of the invention.

DESCRIPTION OF EMBODIMENTS

Fig. 1 illustrates an environment in which the invention may be practiced, in accordance with an embodiment of the invention. The environment includes an air- conditioning system. Air conditioning system 100 is a split-type air conditioner that includes an evaporator 102, a condensing unit 104, including condenser coils, preferably placed outdoors, and a linkage 106. Linkage 106 connects evaporator 102 to condensing unit 104. Linkage 106 may include a conduit that houses a power cable, refrigerant tubing and suction tubing. It will be apparent to a person skilled in the art that a split-type air conditioner has been mentioned for illustrative purpose only. It does not restrict the scope of the invention in any way, and the invention is equally applicable to other devices.

Fig. 2 illustrates various components of a condensing unit 104, in accordance with an embodiment of the invention. Condensing unit 104 includes a base pan 202. Base pan 202 is supported on two supporting elements 204. Base pan 202 supports the elements of condensing unit 104. A front panel 210, a back panel (not shown), and two side panels 206 are mounted on base pan 202. Condensing unit 104 also includes a propeller fan 212, which blows air on the condenser coils (not shown).

Fig. 3 illustrates various elements of a base pan 202 of a condensing unit 104, in accordance with an embodiment of the invention. Base pan 202 includes a condensate- collecting surface 302. Condensate-collecting surface 302 is extended to form an upward rim 308, in order to attach front panel 210, back panel and side panels 206 to base pan 202. Condensate-collecting surface 302 is supported by supporting elements 204. In an embodiment of the invention, supporting elements 204 are removably or permanently fastened to base pan 202. According to another embodiment of the invention, supporting elements 204 may be integrated in base pan 202, to form a self- supporting structure.

A knock-out drain hole 304 is formed by cutting out a piece from condensate- collecting surface 302. Condensate-collecting surface 302 may include more than one knock-out drain holes 304. In an embodiment of the invention, a drain hole 306 is provided on condensate-collecting surface 302. A drain pipe can be connected to drain hole 306 for the removal of condensate collected in base pan 202. In an embodiment of the invention, multiple drain pipes can be connected to multiple drain holes 306.

In cold environments, when air conditioning system 100 works in the heating mode, the condensate, formed on the condenser coil drips on base pan 202. This condensate is collected on condensate-collecting surface 302. When the atmospheric temperature drops below the freezing point of the condensate, the condensate freezes in base pan 202, resulting in ice formation. The ice can be removed by dismantling the condensing unit assembly and removing base pan 202 thereby. Alternatively, knock-out drain holes 304 are provided on base pan 202, for removing the ice.

In an embodiment of the invention, base pan 202 is made of sheet metal. It will be apparent to a person skilled in the art that the material of base pan 202 may be any metal, alloy, composite, plastic or polymer. In addition, the thickness of the material may vary, depending on manufacturing requirements.

Fig. 4 illustrates the formation of sealed knock-out drain holes 304 in a condensing unit, in accordance with an embodiment of the invention. Fig. 4A shows an upside-down view of base pan 202. A knock-out cover 402 is cut out from condensate- collecting surface 302 to form knock-out drain hole 304. In an embodiment of the invention, knock-out drain holes 304 are formed by means of blanking operation. In another embodiment, the knock-out drain holes are formed by using a Computer Numeric Control (CNC) machine or by a laser-cutting operation. A force of order 11-15 ton is applied by means of a blanking die to cut out knock-out cover 402. It will be apparent to a person skilled in the art that the force and the cutting-out operation may vary depending on the material of condensate-collecting surface 302.

Knock-out cover 402 is cut in such a way that it has one or more protrusions ^' extending from its perimeter. The protrusions provide support for the knock-out cover 402 to fit into knock-out drain hole 304.

In an embodiment of the invention, knock-out cover 402 is fitted in knock-out drain hole 304 by means of a nitrogen cyliήder-piston arrangement, as shown in Fig. 4B. The arrows in Fig.4B indicate the direction of the pressure to be applied by means of the nitrogen piston-cylinder arrangement. It will be apparent that any other force-exerting means that generates force of the order 11-15 ton can be used to fit knock-out cover 402 into knock-out drain hole 304. The protrusions provided on knock-out cover 402 facilitate the sealing of knock-out cover 402 to knock-out drain hole 304. A force from the opposite direction can be applied to remove knock-out cover 402 from knock-out drain hole 304. The force can be applied manually with hand or using a hammer.

In an embodiment of the invention, more than one knock-out drain holes are provided on condensate-collecting surface 302, and a corresponding number of knockout covers are provided to seal the knock-out drain holes. One such arrangement is illustrated in Fig.4. Knock-out drain hole 406 has a knock-out cover 404 sealed to it.

Fig. 5 illustrates the dimensions of a knock-out cover 402 of a base pan 202 of a condensing unit 104, in accordance with an embodiment of the invention. Knock-out cover 402 is a hexagonal-shaped piece cut from condensate-collecting surface 302, with four protrusions 502, spaced along the perimeter, on four of its sides. In an embodiment of the invention, protrusion 502 is formed by using a blanking die. Protrusion 502 is an arc of a circle having diameter between 2 mm and 5 mm. The length of protrusion 502 may be between 0.2 mm and 1 mm. Further, the angle of protrusion 502 may be between 40 and 60 degrees. In an embodiment of the invention, the diameter of circle of protrusion 502 is 3 mm, its length^'0.5 mm, and its angle 45 degrees. In addition, the protrusions may be identical or non-identical. It will be apparent that the protrusions can be of any other dimensions apart from those given above. According to various embodiments of the invention, the shape of knock-out cover 402 may be, but not limited to, a regular polygon, a star polygon, an uneven polygon, a crescent, a circle, an ellipse, and an oval. Generally, the greater number of protrusions along the perimeter of the knock-out cover provides a greater sealing surface and in some instances a stronger seal.

Fig. 6 is a flowchart illustrating a method for manufacturing a base pan 202 of a condensing unit 104, in accordance with an embodiment of the invention. Base pan 202 is provided with knock-out drain holes 304 in order to drain out the condensate or remove the ice formed on condensate-collecting surface 302. At step 602, the process of manufacturing base pan 202 is initiated. At step 604, a piece is cut out from condensate-collecting surface 302. According to an embodiment of the invention, the piece is cut by means of a blanking operation. The piece is cut from condensate- collecting surface 302 of base pan 202 in such a way that it forms knock-out cover 402. Further, knock-out cover 402 has protrusions 502 extending from its perimeter. At step 606, knock-out cover 402 is attached to knock-out drain hole 304, such that knock-out drain hole 304 gets sealed. Protrusions 502 enable the sealing of knock-out cover 402 to knock-out drain hole 304. In an embodiment of the invention, knock-out cover 402 is attached to knock-out drain hole 304 by means of a nitrogen cylinder-piston arrangement. It will be apparent that any other pressure-exerting means that generates pressure of the order 11-15 ton can be used to fit knock-out cover 402 into knock-out drain hole 3O4.Thereafter, the process is terminated at step 608.

The embodiments of the invention provide one or more of the following advantages. The system is simple in design, cost-effective, easy to implement, and entails minimal maintenance cost. Further, it provides knock-out drain holes that are sealed. Moreover, it works even when there is ice formation in the base pan at extremely low temperatures.

While the preferred embodiments of the invention have been illustrated and described, it will be clear that the invention is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the invention, as described in the claims.

Claims

What is claimed is:

1. A condensate removal system for a condensing unit, the condensate removal system comprising: a condensate-collecting surface comprising a knock-out drain hole; and a knock-out cover configured to fit in the knock-out drain hole, the knock-out cover comprising a protrusion extending from a perimeter of the knock-out cover, wherein the protrusion removably attaches the knock-out cover to the condensate- collecting surface.

2. The condensate removal system according to claim 1 , wherein the knock-out cover comprises a plurality of protrusions extending from the perimeter of the knock-out cover.

3; The condensate removal system according to claim 2, wherein the plurality of protrusions are spaced around the perimeter.

4. The condensate removal system according to claim 2, wherein the plurality of protrusions are angled.

5. The condensate removal system according to claim 4, wherein angle of the plurality of protrusions is between 40 degrees and 60 degrees.

6. The condensate removal system according to claim 2, wherein the plurality of protrusions are arcs of a circle with diameters between 2 mm and 5 mm and lengths between 0.2 mm and 1 mm.

7. The condensate removal system according to claim 1, wherein the condensate- collecting surface is made of one or more materials selected from the group comprising metal, alloy, composite, plastic, and polymer.

8. The condensate removal system according to claim 1, wherein the knock-out cover is cut from the condensate-collecting surface.

9. The condensate removal system according to claim 1 further comprising a plurality of supporting elements for supporting the condensing unit.

10. An air conditioning system comprising: a refrigeration system comprising an evaporator and a condensing unit; a condenser coil located inside the condensing unit; a propeller fan blowing air on the condenser coil; and a base pan comprising: a condensate-collecting surface comprising a knock-out drain hole, wherein condensate from the condenser coil is collected on the condensate- collecting surface; and a knock-out cover configured to fit in the knock-out drain hole, the knockout cover comprising a protrusion extending from a perimeter of the knock-out cover, wherein the protrusion removably attaches the knock-out cover to the condensate-collecting surface.

11. The air conditioning system according to claim 10, wherein the knock-out cover comprises a plurality of protrusions extending from the perimeter of the knock-out cover.

12. The air conditioning system according to claim 11 , wherein the plurality of protrusions are spaced around the perimeter.

13. The air conditioning system according to claim 11, wherein the plurality of protrusions are angled.

14. The air conditioning system according to claim 11 , wherein angle of the plurality of protrusions is between 40 degrees and 60 degrees.

15. The air conditioning system according to claim 11, wherein the plurality of protrusions are arcs of a circle with diameters between 2 mm and 5 mm and lengths between 0.2 mm and 1 mm.

16. The air conditioning system according to claim 10, wherein the condensate- collecting surface is made of one or more materials selected from the group comprising metal, alloy, composite, plastic, and polymer.

17. The air conditioning system according to claim 10, wherein the knock-out cover is cut from the condensate-collecting surface.

18. The air conditioning system according to claim 10 further comprising a plurality of supporting elements connected to the base pan for supporting the condensing unit.

19. The air conditioning system according to claim 10, wherein the air conditioning system is a split-type air conditioner.

20. A method for manufacturing a base pan for a condensing unit, the base pan comprising a condensate-collecting surface, the method comprising the steps of: cutting out a knock-out cover comprising a plurality of protrusions, from the condensate-collecting surface, wherein a knock-out drain hole is formed; and attaching the knock-out cover to the knock-out drain hole to seal the knock-out drain hole, wherein the sealing is ensured due to the plurality of protrusions.