Refrigerant recovery system

• US 5,548,966 A
• Filed: 06/07/1995
• Issued: 08/27/1996
• Est. Priority Date: 05/03/1993
• Status: Expired due to Fees

• Current Assignee: Copeland Corporation LLC (Emerson Electric Company)
• Original Assignee: Copeland Corporation LLC (Emerson Electric Company)
• Inventors: Tinsler, Theodore E.
• Primary Examiner(s): Sollecito, John M.
• Application Number:
  US08/478,405
• Time in Patent Office: 447 Days
• Field of Search: 62/77, 62/292, 62/149, 62/126, 62/129
• US Class Current: 62/77
• CPC Class Codes: B60H 1/00585 Means for monitoring, testing or servicing the air-conditioning
• CPC Class Codes: F25B 2345/002 Collecting refrigerant from a cycle
• CPC Class Codes: F25B 45/00 Arrangements for charging or discharging refrigerant

Abstract

Two preferred embodiments of an improved refrigerant recovery system and method for recovering refrigerant from a separate system are disclosed whereby the first embodiment utilizes a closed-loop refrigeration system employing a portable storage tank to recover refrigerant from a separate system that needs to be serviced. The first embodiment recovers refrigerant from the separate system by placing a storage tank within an evaporator that is cooled by evaporator coils and evacuated by a vacuum pump. The vacuum pump is valved off and recovered refrigerant is directed to the storage tank from the separate system. None of the recovered refrigerant contacts the compressor of the recovery system and vacuum pump. An alternative to the first embodiment provides a booster pump in-line with the storage tank and the separate system for transferring any residual refrigerants into the storage tank. The second preferred embodiment includes a portable storage tank located within an insulation device and a number of other conventional components including a compressor, condenser, valves and an expansion device. This system employs two phases whereby during phase 1 primarily liquid refrigerant is directed to the storage tank which enhances the life of the compressor because contaminated liquid refrigerants are not subjected to the compressor. Once all of the liquid has been recovered from the separate system and a predetermined pressure is reached in the storage tank, phase 2 is activated whereby primarily recovered gas is directed through the compressor and eventually dumped into the cooled storage tank. Because of this unique arrangement, refrigerants can be recovered from separate systems at much faster rates then conventional refrigerant recovery systems. An alternative to this second embodiment provides a unique fluid sensor which improves the efficiency of the recovery system by automatically activating phase 2 when all of the liquid refrigerant has been recovered from the separate system and when the storage tank is at a predetermined pressure.

Claims

1. A method of reclaiming fluid from a separate refrigeration system comprising the steps of:

providing an insulating device, a portable fluid storage tank, a compressor, and a condenser;

inserting the storage tank within the insulating device;

connecting the storage tank to the separate refrigeration system;

reducing the temperature within the storage tank;

transferring both a liquid component and a gaseous component of the reclaimed fluid into the storage tank until substantially all of the liquid component has been recovered; and

switching to another mode of operation where the reclaimed fluid is primarily a gaseous component, said switching step comprising

a) routing the reclaimed fluid to the compressor for a time period to create compressed reclaimed fluid;

b) condensing the compressed reclaimed fluid to create condensed reclaimed fluid; and

c) directing the condensed reclaimed fluid to the storage tank.

2. The method according to claim 1, wherein the transferring step includes combining the liquid component and the gaseous component during a first mode of operation.

3. The method according to claim 1, wherein the switching step includes automatically sensing the reclaimed fluid in order to determine if there is present a liquid component.

4. A process of a system reclaiming fluid from a separate system comprising:

providing an insulating device, a portable fluid storage tank, a compressor, a condenser;

a pressure switch, and an expansion device;

inserting the storage tank within the insulating device;

connecting the storage tank to the separate system;

reducing the temperature within the storage tank;

sensing the pressure within the storage tank with the pressure switch;

rerouting the reclaimed fluid to the compressor to produce compressed reclaimed fluid;

condensing the compressed reclaimed fluid to produce condensed reclaimed fluid;

routing the condensed reclaimed fluid through the expansion device to produce expanded reclaimed fluid; and

delivering the expanded reclaimed fluid to the storage tank.

5. The process according to claim 4, further comprising:

deactivating the compressor when the pressure within the storage tank reaches a predetermined value.

6. The process according to claim 4, further comprising:

creating a vacuum in the separate system sufficient to remove substantially all fluid from said separate system.

7. The process according to claim 4, wherein during said transferring step substantially all liquid refrigerant from the separate system is transferred into the storage tank.

8. A process of a refrigeration system reclaiming gaseous and liquid refrigerant from an independent refrigeration system, the process comprising:

providing an insulating device, a refrigerant storage tank, and a compressor;

a first phase of operation including;

connecting the independent refrigeration system to the storage tank;

inserting the storage tank within the insulation device;

cooling the storage tank and reducing the pressure therein;

transferring reclaimed refrigerant to the storage tank;

sensing the pressure within the storage tank;

a second phase of operation including;

rerouting the refrigerant being reclaimed from the independent refrigeration system to the compressor to produce compressed reclaimed refrigerant; and

transferring the compressed reclaimed refrigerant to the storage tank.

9. The process according to claim 8, wherein the first phase is continued until nearly all liquid refrigerant is recovered from the independent refrigeration system.

10. The process according to claim 8, further comprising a fluid sensor and wherein the first phase is continued until the fluid sensor no longer senses liquid refrigerant and the pressure with the storage tank reaches a predetermined pressure.

11. The process according to claim 8, wherein the second phase is capable of producing pressures of 20 inches of mercury within the independent refrigeration system.

12. The process according to claim 8, wherein the second phase operates until the saturation pressure within the storage tank is greater than the ambient temperature by a predetermined value.

13. The process according to claim 8, wherein the first and second phases may be sequenced with one another.

14. The process according to claim 8, wherein said refrigeration system is transportable.

15. The process according to claim 8, further comprising:

providing check valves and solenoid valves;

sequencing the opening and closing of said solenoid valves during said phases to control the routing of the refrigerant being reclaimed.

16. The process according to claim 8, wherein the storage tank is portable.