Prefilter System for Heat Transfer Unit and Method

• US 20080034776A1
• Filed: 08/08/2006
• Published: 02/14/2008
• Est. Priority Date: 08/09/2005
• Status: Active Grant

• Current Assignee: Tim Allan Nygaard Jensen
• Original Assignee: Tim Allan Nygaard Jensen
• Inventors: Jensen, Tim Allan Nygaard
• Granted Patent: US 7,805,953 B2
• Time in Patent Office: Days
• US Class Current: 62/305
• CPC Class Codes: F24F 1/027 mounted in wall openings, e.g. in windows
• CPC Class Codes: F24F 8/10 by separation, e.g. by filtering
• CPC Class Codes: F24F 8/108 using dry filter elements
• CPC Class Codes: F25B 2339/041 of evaporative condensers
• CPC Class Codes: F25B 2500/09 Improving heat transfers
• CPC Class Codes: F25B 39/04 Condensers
• CPC Class Codes: F25B 47/00 Arrangements for preventing or removing deposits or corrosion, not provided for in another subclass

Abstract

A method of transferring heat is accomplished by providing a heat exchanger unit that is at least partially air cooled. The heat exchanger unit has an evaporator, condenser, compressor and a fan for forcing air over an exteriorly located heat exchange surface of the condenser. A fiberglass filter element is positioned adjacent to the heat exchange surface of the condenser for capturing at least one of grease, debris and other contaminants that are not entrained within any liquid cooling fluid that would otherwise contact the heat exchange surface. The filter element is allowed to capture the at least one of grease, debris and other contaminants prior to contact with the heat exchange surface of the condenser.

Claims

1. A method of transferring heat comprising:

providing heat exchanger unit that is at least partially air cooled, the heat exchanger unit having an evaporator, condenser, compressor and a fan for forcing air over an exteriorly located heat exchange surface of the condenser;

positioning a fiberglass filter element adjacent to the heat exchange surface of the condenser for capturing at least one of grease, debris and other contaminants that are not entrained within any liquid cooling fluid that would otherwise contact the heat exchange surface; and

allowing the filter element to capture the at least one of grease, debris and other contaminants prior to contact with the heat exchange surface of the condenser.

2. The method of claim 1, wherein:

the filter element effectively surrounds the heat exchange surface of the condenser so that substantially no non-filtered air contacts the heat exchange surface.

3. The method of claim 1, wherein:

the filter element exhibits a pressure loss of from about 15 to about 25 Pa at a face velocity of from about 1 to 1.25 m/s.

4. The method of claim 1, wherein:

the filter element is a woven or non-woven fiberglass filter element.

5. The method of claim 1, wherein:

the filter element is formed from a hydrophilic material.

6. The method of claim 1, wherein:

the filter element has a MERV rating of from 1 to 12.

7. The method of claim 1, wherein:

the condenser is positioned at a location wherein exhaust from a kitchen exhaust fan comes into contact with the filter element.

8. The method of claim 1, further comprising:

providing a mist generator having at least one nozzle for directing a stream of fine mist or atomized liquid coolant into the air between the filter element and the heat exchange surface of the condenser, the mist generator being coupled to a supply of liquid coolant; and

controlling the degree of mist or atomized coolant generated by the mist generator with a controller.

9. The method of claim 8, further comprising:

positioning a second filter element between the at least one nozzle and the heat exchange surface for capturing droplets of liquid coolant, the at least one nozzle being spaced apart from the filter element;

and directing the stream of mist or atomized liquid coolant directly into the air between the first and second elements.

10. The method of claim 1, wherein:

the filter element is utilized without any evaporative liquid coolant pre-cooler system.

11. The method of claim 1, wherein the filter element comprises:

a filter frame attached to or supported by the heat exchanger unit;

a filter housing that secures to the rack or frame, and

a replaceable or washable filter media that is housed within the filter housing.

12. The method of claim 11, wherein:

the filter frame includes channels or flanges for supporting the filter housing.

13. The method of claim 11, wherein:

the filter frame includes fasteners for fastening the filter element to the heat exchange unit.

14. The method of claim 11, wherein:

the filter housing includes a generally rigid mesh panel against which the filter media abuts that allows air to pass therethrough.

15. The method of claim 1, wherein:

the filter element is coupled directly to the heat exchange surface of the condenser or an opening of the heat exchanger unit to the heat exchange surface of the condenser.

16. The method of claim 1, further comprising:

providing a sensor for monitoring the pressure differential across the filter element.

17. A method of transferring heat comprising:

providing heat exchanger unit that is at least partially air cooled, the heat exchanger unit having an evaporator, condenser, compressor and a fan for forcing air over a heat exchange surface of the condenser;

positioning a filter element adjacent to the heat exchange surface of the condenser for capturing at least one of grease, debris and other contaminants that are not entrained within any liquid cooling fluid that would otherwise contact the heat exchange surface;

allowing the filter element to capture the at least one of grease, debris and other contaminants prior to contact with the heat exchange surface of the condenser.

providing a mist generator having at least one nozzle for directing a stream of fine mist or atomized liquid coolant into the air between the filter element and the heat exchange surface of the condenser, the mist generator being coupled to a supply of liquid coolant; and

controlling the degree of mist or atomized coolant generated by the mist generator with a controller.

18. The method of claim 17, further comprising:

positioning a second filter element between the at least one nozzle and the heat exchange surface for capturing droplets of liquid coolant, the at least one nozzle being spaced apart from the filter element;

and directing the stream of mist or atomized liquid coolant directly into the air between the first and second elements.