US3370438A - Condensing pressure controls for refrigeration system - Google Patents

Condensing pressure controls for refrigeration system Download PDF

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US3370438A
US3370438A US54751266A US3370438A US 3370438 A US3370438 A US 3370438A US 54751266 A US54751266 A US 54751266A US 3370438 A US3370438 A US 3370438A
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refrigerant
condenser
coil
refrigeration
compressor
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Harold H Hopkinson
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Carrier Global Corp
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Carrier Corp
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT-PUMP SYSTEMS
    • F25B49/00Arrangement or mounting of control or safety devices
    • F25B49/02Arrangement or mounting of control or safety devices for compression type machines, plant or systems
    • F25B49/027Condenser control arrangements
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S62/00Refrigeration
    • Y10S62/17Condenser pressure control

Description

Feb. 27, 1968 H. H. HOPKINSON 3,370,438

CONDENSING PRESSURE CONTROLS FOR REFRIGERATION SYSTEM Filed May 4, 1966 I5 lo I2 INVENTOR.

HAROLD H. HOPMNSON.

WZWW

ATTORNEY.

United States Patent 337,438 Patented Feh. 27, 1968 Free 3,370,438 CQNDENSENG PRESSURE CONTRGLS FOR REFRIGERATION SYSTEM Harold H. Hopkinson, Manlius, N.Y., assiguor to Carrier Corporation, Syracuse, N.Y., a corporation of Delaware Filed May 4, 1966, Ser. No. 547,512 3 Claims. (Cl. 62-196) This invention relates to a refrigeration system and, more particularly, to an arrangement for controlling condensing pressures in a refrigeration system.

To sustain capacity of a refrigeration system, it is essential that an adequate pressure differential be held across the system expansion device. Where the system is of the type having an air-cooled condenser, the pressure differential across the expension device is largely dependent upon outdoor temperature conditions. When outdoor temperatures are low, pressures within the condenser fall while the condensing rate increases, and the pressure differential across the expansion device drops.

To offset the increased condensing rate, such as occurs in air cooled condensers at low outdoor temperatures, portions of the condenser may be isolated from the system. However, refrigerant as well as oil may be trapped in the separated or isolated portions of the condenser which can reduce system elficiency and cause over-heating of the compressor.

It is a principal object of the present invention to provide a new and improved refrigeration system.

It is a further object of the present invention to provide an arragement for controlling head pressure in a refrigeration system by isolating portions of the system condenser without concurrent trapping of refrigerant and lubricant.

It is a further object of the present invention to provide an improved head pressure control for refrigeration systems incorporating means to return to the system refrigerant and lubricant in those parts of the condenser separated from the system.

It is an object of the present invention to provide a refrigeration system employing alternately usable condensers incorporating means to insure return of refrigerant and lubricant trapped in the d condenser to the system.

This invention relates to a refrigeration system comprising in combination, a compressor with suction and discharge sides; refrigerant expansion means; and evaporator series-connected between the expansion means and the suction side of the compressor; condenser means arranged between the discharge side of the compressor and the refrigerant expansion means, the condenser means including at least two coil sections circuited to provide parallel refrigerant flow paths; first valve means between at least one of the condenser coil sections and the discharge side of the compressor effective when actuated to interrupt flow of refrigerant from the compressor to the one coil section; a conduit for returning refrigerant and lubricant trapped in the one condenser coil section to the system, the conduit communicating with the system downstream of the refrigerant expansion means, and including a restricted portion to control the flow of returning refrigerant and lubricant from the one condenser coil section to the system; and second valve means for preventing flow of refrigerant from the other of the condenser coil sections into the one condenser coil section.

Other objects of the invention will be perceived from the ensuing description and drawings in which:

FIGURE 1 is a schematic view showing a refrigeration system with head pressure control incorporating the refrigerant and lubricant return arrangement of the present invention, and

FIGURE 2 is a schematic view of a modified refrigeration system having a pluraiity of alternating usable condeners incorporating the refrigerant and lubricant return means of the present invention,

Referring to FIGURE 1 of the drawings, refrigeration system 10 includes outdoor coil or condenser 12 series connected with the discharge side of a suitable refrigerant compression means 14 by line 15. In the exemplary arrangement of FIGURE 1, condenser 12 is comprised of coil sections 16, 17, 18 providing parallel paths to refrigerant flow. Coil sections 17, 18 are connected to refrigerant line 15 through control valves 20, 21, which may be conveniently operated by solenoids 2t), 21 respectively. Whiie condenser 12 is illustrated as comprising three separate and individual coil sections, 16, 17, 18, it is understood that the number of coil sections may be varied to suit individual applications.

Check valves 26, 27 series connect coil sections 17, 18

espectively with refrigerant line 29 and a suitable refrigerant expansion device such as thermal valve 30. Check valves 26, 27 permit flow of refrigerant from condenser coil sections 17, 18 to valve while preventing opposite flow of refrigerant from coil section 16 and line 29 into coil sections 17, 13 as will be more apparent hereinafter.

While the refrigerant expansion device is illustrated as comprising a thermal expansion valve 30, other suitable expansion devices such as a capillary tube may be contemplated.

Refrigerant line 32 connects expansion valve 3t) with indoor coil or evaporator 35. Refri erant line connects the outlet side of evaporator 35 to the suction side of compressor 14 to complete the refrigeration system 10.

Refrigerant bypass or drain lines 40, 41connect the outlet side of condenser coil sections 17, 18 upstream of check valves 26, 27 with refrigerant line 32 downstream of expansion valve 36. Drain lines 4%), 41 each include a restricted part such as capillary section 43, 44 respectively. Capillary sections 43, 44 permit the controlled egress of liquid refrigerant and lubricant from condenser sections 1", 18 to the system.

With control valves 2t 21, relatively hot, high pressure refrigerant from compressor 14 passes via line 15 into coil sections 111, 17, 18 of condenser 12 Where the refrigerant is condensed. Liquid refrigerant from coil sections 16, 17, 1S flows through line 29 to expansion valve 39. Relatively low pressure liquid refrigerant from expansion valve 30 passes through line 32 to evaporator coil 35 wherein the liquid refrigerant is vaporized. Vaporized refrigerant from evaporator 35 returns through line 36 to the suction side of compressor 14. A relatively small amount of liquid refrigerant in condenser coil sections 17, 18 may flow through drain lines 4%, 41 and capillary sections .3, 44 thereof into line 32 and the system bypassing expansiou valve 3%.

On an increase in system condensing rate, as for example, when outdoor ambient temperatures become low, solenoid 21 may be energized from a suitable power source (not shown) to close control valve 21 and interrupt the flow of refrigerant to condenser coil section 18. it is understood that condenser coil sections 16, 17 continue to function in the usual manner. With closure of valve 21, pressure in condenser coil section 18 soon approximates the pressure downstream of expansion valve 39, that is, system low side pressure. As pressure in coil section 18 decreases, coil section 18 in effect functions as an evaporator, and refrigerant and lubricant trapped therewithin by closure of valve 21 returns through line 41 and capillary section 44 to the system. Check valve 27 effectively prevents flow of refrigerant from condenser sections 16, 17 into condenser section 18. Refrigerant which leaks past valve 27 into condenser sec tion 18 returns through line 41 and capillary 44 into line It is understood that a further reduction in condenser capacity may be effected by energizing solenoid 26' to close control valve 29 and interrupt fiow of refrigerant into condenser section 17.-Check valve 26 prevents ingress of refrigerant from section 16 into condenser section 17 while line permits refrigerant and lubricant trapped in condenser section 17 to return to the system.

Check valves in drain lines 40, 41 obviate reverse flow of refrigerant from evaporator 35 to condenser section 17 and/or 18 when control valves 20 and/ or 21 are closed.

Referring to FIGURE 2 of the drawings, there is shown a refrigeration system 49 arranged to permit selective use of either air-cooled condenser or liquid-cooled condenser 56. Referring thereto, refrigerant line 5% connects the discharge side of a suitable refrigerant com pression means 52 through control valves 53, 54 with condensers 55, 56 respectively. Valves 59, 60 connect condensers 55, 56 respectively with refrigerant line 62 and a suitable refrigerant expansion device such as thermal valve 63. Line 64 connects expansion valve 63 with the system evaporator coil 65. Refrigerant line 68 connects evaporator coil with the suction side of compression means 52 to complete the refrigeration system 49.

Drain lines 70, 71 each with a capillary type restrictor 72, 73 respectively, communicate the outlet side of condensers 55, 56 upstream of control valves 59, 60 with refrigerant line 64. While condensers 55, 56 are illustrated as being air and liquid cooled types of condensers respectively, it is appreciated that condensers 55, 56 both may be either air or liquid cooled.

When air-cooled condenser 55 is functioning, valves 54, 60 are closed isolating the liquid-cooled condenser 56 through line and capillary 72 thereof into the refrigeration system.

While I have described a preferred embodiment of my invention, it will be understood that my invention is not limited thereto since it may be otherwise embodied Within the scope of the following claims.

I claim:

1. In a refrigeration system including a compressor with suction and discharge sides, refrigerant expansion means, and an evaporator series-connected between said expansion means and the suction side of said compressor, the combination of: condenser means arranged between the discharge side of said compressor and said refrigerant expansion means, said condenser means including at least two coil sections circuited to provide parallel refrigerant flow paths; first valve means between at least one of said condenser coil sections and the discharge side of said compressor effective when actuated to interrupt fiow of refrigerant from said compressor to said one coil section; a conduit for returning refrigerant and lubricant trapped in said one condenser coil section to said system, said conduit communicating with said system downstream of said refrigerant expansion means, and including a restricted portion to control the flow of returning refrigerant and lubricant from said one condenser coil section to said system; and second valve means for preventing flow of refrigerant from the other of said condenser coil sections into said one condenser coil section.

2. A refrigeration system according to claim 1 including third valve means for preventing reverse flow of refrigerant from said system through said conduit into said one condenser coil section.

3. A refrigeration. system according to claim 1 in which said conduit restricted portion comprises a capillary.

References Cited UNITED STATES PATENTS 2,933,904 4/ 1960 Wellman 62-196 XR 3,010,289 11/1961 Kuklinski 6'2l96 3,111,815 11/1963 Roberts 62--196 XR MEYER PERLIN, Primary Examiner.

Claims (1)

1. IN A REFRIGERATION SYSTEM INCLUDING A COMPRESSOR WITH SUCTION AND DISCHARGE SIDES, REFRIGERANT EXPANSION MEANS, AND AN EVAPORATOR SERIES-CONNECTED BETWEEN SAID EXPANSION MEANS AND THE SUCTION SIDE OF SAID COMPRESSOR, THE COMBINATION OF : CONDENSER MEANS ARRANGED BETWEEN THE DISCHARGE SIDE OF SAID COMPRESSOR AND SAID REFRIGERANT EXPANSION MEANS, SAID CONDENSER MEANS INCLUDING AT LEAST TWO COIL SECTIONS CIRCUITED TO PROVIDE PARALLEL REFRIGERANT FLOW PATHS; FIRST VALVE MEANS BETWEEN AT LEAST ONE OF SAID CONDENSER COIL SECTIONS AND THE DISCHARGE SIDE OF SIDE COMPRESSOR EFFECTIVE WHEN ACTUATED TO INTERRUPT FLOW OF REFRIGERANT FROM SAID COMPRESSOR TO SAID ONE COIL SECTION; A CONDUIT FOR RETURNING REFRIGERANT AND LUBRICANT TRAPPED IN SAID ONE CONDENSER COIL SECTION TO SAID SYSTEM, SAID CONDUIT COMMUNICATING WITH SAID SYSTEM DOWNSTREAM OF SAID REFRIGERANT EXPANSION MEANS, AND INCLUDING A RESTRICTED PORTION TO CONTROL THE FLOW OF RETURNING REFRIGERANT AND LUBRICANT FROM SAID ONE CONDENSER COIL SECTION TO SAID SYSTEM; AND SECOND VALVE MEANS FOR PREVENTING FLOW OF REFRIGERANT FROM THE OTHER OF SAID CONDENSER COIL SECTIONS INTO SAID ONE CONDENSER SECTION.
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Cited By (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3440833A (en) * 1967-11-09 1969-04-29 United Aircraft Prod Vapor cycle refrigeration system
US3481152A (en) * 1968-01-18 1969-12-02 Frick Co Condenser head pressure control system
US3529432A (en) * 1968-10-16 1970-09-22 Otto J Nussbaum Refrigeration system for widely varying ambient conditions
US3631686A (en) * 1970-07-23 1972-01-04 Itt Multizone air-conditioning system with reheat
US3635041A (en) * 1970-07-13 1972-01-18 Carrier Corp Heating and cooling refrigeration apparatus
US3643462A (en) * 1970-09-18 1972-02-22 Westinghouse Electric Corp Variable capacity refrigeration system and controls
US3665724A (en) * 1970-07-13 1972-05-30 Carrier Corp Heating and cooling refrigeration apparatus
US3720072A (en) * 1971-02-26 1973-03-13 Union Carbide Corp Apparatus for the recovery of halocarbons
US3994142A (en) * 1976-01-12 1976-11-30 Kramer Daniel E Heat reclaim for refrigeration systems
US4262488A (en) * 1979-10-09 1981-04-21 Carrier Corporation System and method for controlling the discharge temperature of a high pressure stage of a multi-stage centrifugal compression refrigeration unit
US4679411A (en) * 1978-08-16 1987-07-14 American Standard Inc. Stepped capacity constant volume building air conditioning system
US5065584A (en) * 1990-07-30 1991-11-19 U-Line Corporation Hot gas bypass defrosting system
US5101640A (en) * 1989-12-01 1992-04-07 Hitachi, Ltd. Air conditioning apparatus, heat exchanger for use in the apparatus and apparatus control method
US5291749A (en) * 1992-12-23 1994-03-08 Schulak Edward R Energy efficient domestic refrigeration system
US5402651A (en) * 1992-12-23 1995-04-04 Schulak; Edward R. Energy efficient domestic refrigeration system
US5415006A (en) * 1993-11-18 1995-05-16 Thermo King Transport refrigeration unit having means for increasing the amount of refrigerant charge available
US5666817A (en) * 1996-12-10 1997-09-16 Edward R. Schulak Energy transfer system for refrigerator/freezer components
US5669223A (en) * 1995-02-08 1997-09-23 Thermo King Corporation Transport temperature control system having enhanced low ambient heat capacity
US5743109A (en) * 1993-12-15 1998-04-28 Schulak; Edward R. Energy efficient domestic refrigeration system
US5775113A (en) * 1992-12-23 1998-07-07 Schulak; Edward R. Energy efficient domestic refrigeration system
US5791154A (en) * 1992-12-23 1998-08-11 Schulak; Edward R. Energy transfer system for refrigeration components
US5937662A (en) * 1996-12-10 1999-08-17 Edward R. Schulak Energy transfer system for refrigerator/freezer components
US5964101A (en) * 1996-12-10 1999-10-12 Edward R. Schulak Energy transfer system for refrigerator/freezer components
US6418735B1 (en) * 2000-11-15 2002-07-16 Carrier Corporation High pressure regulation in transcritical vapor compression cycles
US6560978B2 (en) 2000-12-29 2003-05-13 Thermo King Corporation Transport temperature control system having an increased heating capacity and a method of providing the same
US6751967B1 (en) * 2003-06-05 2004-06-22 Chun Hung Chen Multifunction air conditioning device
US20060288716A1 (en) * 2005-06-23 2006-12-28 York International Corporation Method for refrigerant pressure control in refrigeration systems
EP1909049A2 (en) * 2006-10-06 2008-04-09 Hussmann Corporation Electronic head pressure control
US20080229764A1 (en) * 2005-09-15 2008-09-25 Taras Michael F Refrigerant Dehumidification System with Variable Condenser Unloading
US20130340455A1 (en) * 2012-06-22 2013-12-26 Hill Phoenix, Inc. Refrigeration system with pressure-balanced heat reclaim
US20160161163A1 (en) * 2014-12-09 2016-06-09 Lennox Industries Inc. Variable refrigerant flow system operation in low ambient conditions
US10048025B2 (en) 2013-01-25 2018-08-14 Trane International Inc. Capacity modulating an expansion device of a HVAC system
US10782053B1 (en) 2018-05-09 2020-09-22 Otg, Llc Single stage, single phase, low pressure refrigeration system

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2933904A (en) * 1957-03-15 1960-04-26 Carrier Corp Refrigeration system
US3010289A (en) * 1959-04-14 1961-11-28 Carrier Corp Refrigeration system with variable speed compressor
US3111815A (en) * 1962-04-20 1963-11-26 Westinghouse Electric Corp Controls for refrigeration systems having air cooled condensers

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2933904A (en) * 1957-03-15 1960-04-26 Carrier Corp Refrigeration system
US3010289A (en) * 1959-04-14 1961-11-28 Carrier Corp Refrigeration system with variable speed compressor
US3111815A (en) * 1962-04-20 1963-11-26 Westinghouse Electric Corp Controls for refrigeration systems having air cooled condensers

Cited By (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3440833A (en) * 1967-11-09 1969-04-29 United Aircraft Prod Vapor cycle refrigeration system
US3481152A (en) * 1968-01-18 1969-12-02 Frick Co Condenser head pressure control system
US3529432A (en) * 1968-10-16 1970-09-22 Otto J Nussbaum Refrigeration system for widely varying ambient conditions
US3635041A (en) * 1970-07-13 1972-01-18 Carrier Corp Heating and cooling refrigeration apparatus
US3665724A (en) * 1970-07-13 1972-05-30 Carrier Corp Heating and cooling refrigeration apparatus
US3631686A (en) * 1970-07-23 1972-01-04 Itt Multizone air-conditioning system with reheat
US3643462A (en) * 1970-09-18 1972-02-22 Westinghouse Electric Corp Variable capacity refrigeration system and controls
US3720072A (en) * 1971-02-26 1973-03-13 Union Carbide Corp Apparatus for the recovery of halocarbons
US3994142A (en) * 1976-01-12 1976-11-30 Kramer Daniel E Heat reclaim for refrigeration systems
US4679411A (en) * 1978-08-16 1987-07-14 American Standard Inc. Stepped capacity constant volume building air conditioning system
US4262488A (en) * 1979-10-09 1981-04-21 Carrier Corporation System and method for controlling the discharge temperature of a high pressure stage of a multi-stage centrifugal compression refrigeration unit
US5101640A (en) * 1989-12-01 1992-04-07 Hitachi, Ltd. Air conditioning apparatus, heat exchanger for use in the apparatus and apparatus control method
US5065584A (en) * 1990-07-30 1991-11-19 U-Line Corporation Hot gas bypass defrosting system
US5291749A (en) * 1992-12-23 1994-03-08 Schulak Edward R Energy efficient domestic refrigeration system
US5402651A (en) * 1992-12-23 1995-04-04 Schulak; Edward R. Energy efficient domestic refrigeration system
US5791154A (en) * 1992-12-23 1998-08-11 Schulak; Edward R. Energy transfer system for refrigeration components
US5520007A (en) * 1992-12-23 1996-05-28 Schulak; Edward R. Energy transfer system for refrigeration components
US5775113A (en) * 1992-12-23 1998-07-07 Schulak; Edward R. Energy efficient domestic refrigeration system
US5415006A (en) * 1993-11-18 1995-05-16 Thermo King Transport refrigeration unit having means for increasing the amount of refrigerant charge available
US5743109A (en) * 1993-12-15 1998-04-28 Schulak; Edward R. Energy efficient domestic refrigeration system
US5669223A (en) * 1995-02-08 1997-09-23 Thermo King Corporation Transport temperature control system having enhanced low ambient heat capacity
US5666817A (en) * 1996-12-10 1997-09-16 Edward R. Schulak Energy transfer system for refrigerator/freezer components
US5937662A (en) * 1996-12-10 1999-08-17 Edward R. Schulak Energy transfer system for refrigerator/freezer components
US5964101A (en) * 1996-12-10 1999-10-12 Edward R. Schulak Energy transfer system for refrigerator/freezer components
US6230514B1 (en) 1996-12-10 2001-05-15 Edward R. Schulak Energy transfer system for refrigerator freezer components
US6418735B1 (en) * 2000-11-15 2002-07-16 Carrier Corporation High pressure regulation in transcritical vapor compression cycles
US6560978B2 (en) 2000-12-29 2003-05-13 Thermo King Corporation Transport temperature control system having an increased heating capacity and a method of providing the same
US6751967B1 (en) * 2003-06-05 2004-06-22 Chun Hung Chen Multifunction air conditioning device
US7559207B2 (en) * 2005-06-23 2009-07-14 York International Corporation Method for refrigerant pressure control in refrigeration systems
US20060288716A1 (en) * 2005-06-23 2006-12-28 York International Corporation Method for refrigerant pressure control in refrigeration systems
US20080229764A1 (en) * 2005-09-15 2008-09-25 Taras Michael F Refrigerant Dehumidification System with Variable Condenser Unloading
US20080083237A1 (en) * 2006-10-06 2008-04-10 Hussmann Corporation Electronic head pressure control
EP1909049A3 (en) * 2006-10-06 2009-10-14 Hussmann Corporation Electronic head pressure control
EP1909049A2 (en) * 2006-10-06 2008-04-09 Hussmann Corporation Electronic head pressure control
US20130340455A1 (en) * 2012-06-22 2013-12-26 Hill Phoenix, Inc. Refrigeration system with pressure-balanced heat reclaim
US10048025B2 (en) 2013-01-25 2018-08-14 Trane International Inc. Capacity modulating an expansion device of a HVAC system
US10746482B2 (en) * 2013-01-25 2020-08-18 Trane International Inc. Capacity modulating an expansion device of a HVAC system
US20160161163A1 (en) * 2014-12-09 2016-06-09 Lennox Industries Inc. Variable refrigerant flow system operation in low ambient conditions
US10337780B2 (en) * 2014-12-09 2019-07-02 Lennox Industries Inc. Variable refrigerant flow system operation in low ambient conditions
US10782053B1 (en) 2018-05-09 2020-09-22 Otg, Llc Single stage, single phase, low pressure refrigeration system

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