WO2009158612A2 - Procédé de dégivrage par gaz chaud - Google Patents

Procédé de dégivrage par gaz chaud Download PDF

Info

Publication number
WO2009158612A2
WO2009158612A2 PCT/US2009/048850 US2009048850W WO2009158612A2 WO 2009158612 A2 WO2009158612 A2 WO 2009158612A2 US 2009048850 W US2009048850 W US 2009048850W WO 2009158612 A2 WO2009158612 A2 WO 2009158612A2
Authority
WO
WIPO (PCT)
Prior art keywords
refrigerant
evaporator
flow control
compressor
refrigeration system
Prior art date
Application number
PCT/US2009/048850
Other languages
English (en)
Other versions
WO2009158612A3 (fr
Inventor
Feihong Zhang
Jianming Zhang
Original Assignee
Carrier Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Carrier Corporation filed Critical Carrier Corporation
Priority to CN2009801243671A priority Critical patent/CN102077039A/zh
Priority to EP09771143A priority patent/EP2313712A2/fr
Publication of WO2009158612A2 publication Critical patent/WO2009158612A2/fr
Publication of WO2009158612A3 publication Critical patent/WO2009158612A3/fr

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B47/00—Arrangements for preventing or removing deposits or corrosion, not provided for in another subclass
    • F25B47/02—Defrosting cycles
    • F25B47/022—Defrosting cycles hot gas defrosting
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/07—Details of compressors or related parts
    • F25B2400/075—Details of compressors or related parts with parallel compressors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B5/00—Compression machines, plants or systems, with several evaporator circuits, e.g. for varying refrigerating capacity
    • F25B5/02—Compression machines, plants or systems, with several evaporator circuits, e.g. for varying refrigerating capacity arranged in parallel

Definitions

  • This invention relates generally to refrigeration systems and, more particularly, to a hot gas defrost process for defrosting an evaporator of a commercial refrigeration system.
  • evaporators typically include multiple refrigerant vapor compressors, centrally located, that provide refrigerant to a plurality of evaporators.
  • the evaporators may be located at various locations throughout the store in connection with a number of refrigerated merchandisers for displaying refrigerated products, such as diary products, fresh poultry, fish, meat products and produce, or frozen products, such as frozen fish, poultry, meat products, ice cream, frozen confections and other frozen products, and even walk-in cold rooms and freezers.
  • Refrigeration systems of this type include the following basic components: a plurality of refrigerant vapor compressors, at least one condenser, a plurality of evaporators, interconnected in a refrigerant circuit, with an expansion device operatively associated with each evaporator.
  • hot compressed refrigerant vapor discharges from the compressors into the refrigerant circuit and passes through the condenser in heat exchange relationship with a cooling medium, commonly ambient air.
  • a cooling medium commonly ambient air.
  • the refrigerant vapor In traversing the condenser, the refrigerant vapor is condensed to a liquid. The warm, high pressure liquid refrigerant is thence distributed amongst the plurality of evaporators.
  • the warm, high pressure liquid traverses the expansion device operatively associated with that respective evaporator and undergoes an expansion to a lower pressure vapor or liquid/vapor mixture.
  • This lower temperature, low pressure liquid or liquid/vapor mixture thence flows through the evaporator in heat exchange relationship with air from the refrigerated space associated with the evaporator and absorbs heat from the air whereby the air is chilled and the refrigerant is evaporated.
  • the low pressure vapor leaving the evaporators thence returns to the suction inlet of the compressor or a suction manifold supplying a plurality of compressors.
  • frost and/or ice builds up on the respective heat exchange coils of the various evaporators. If the build up becomes excessive, air flow through the evaporator will be reduced as the air flow passage becomes more and more restricted, thereby causing a loss of refrigeration capacity. Consequently, it is customarily practice to defrost the heat exchange coils of the various evaporators, either on demand or at timed intervals, to melt frost and ice accumulated on the heat exchange coils.
  • One method commonly employed to defrost the heat exchange coils of the evaporators is known as hot gas defrost.
  • hot refrigerant vapor discharging from the compressors is redirected to evaporators to be defrosted, rather than passed through the condenser.
  • This redirected hot refrigerant vapor passes through the heat exchange coil of the evaporator being defrosted in a reverse direction.
  • the frost and/or ice accumulated on the heat exchange coil melts and the hot refrigerant vapor cools and condenses to a liquid before leaving the evaporator.
  • this invention is directed at a hot gas defrost process for a refrigeration system having an evaporator to be defrosted, the process characterized by the step of flooding the evaporator to be defrosted with liquid refrigerant prior to supplying hot refrigerant vapor to the evaporator.
  • this invention is directed at a hot gas defrost process for a refrigeration system having an evaporator to be defrosted, the process characterized by the step of suctioning down a refrigerant pressure within the evaporator being defrosted following termination of supplying hot refrigerant vapor to the evaporator.
  • this invention is directed at a hot gas defrost process for a refrigeration system having at least a pair of compressors, at least a pair of evaporators and a condenser disposed in a refrigerant circuit, said hot gas defrost process comprising the steps of: flooding at least one evaporator to be defrosted with liquid refrigerant; supplying hot refrigerant vapor to the liquid flooded evaporator; suctioning down the refrigeration pressure within the evaporator upon termination of the supplying of hot refrigerant vapor to the evaporator being defrosted; and resetting the refrigeration system in condition for operation in a cooling mode.
  • this invention is directed at a refrigeration system including at least a pair of compressors, at least a pair of evaporators and a condenser disposed in a refrigerant circuit, the refrigeration system being selectively operable in a cooling mode of operation and a defrost mode of operation.
  • the refrigeration system includes a plurality of flow control valves disposed in the refrigeration circuit, the flow control valves being selectively positionable in an open position and a closed position.
  • One of the plurality of flow control valves is disposed in a refrigerant line interconnecting a refrigerant suction line to a first of the compressors in fluid flow communication with a refrigerant suction line to a second of the compressors.
  • a refrigeration system including a first compressor and a second compressor disposed in parallel relationship with respect to refrigerant flow, a condenser, a first evaporator and a second evaporator disposed in parallel relationship with respect to refrigerant flow, connected in a refrigerant circuit, a condenser fan operatively associated with the condenser, a first evaporator fan operatively associated with the first evaporator, a second evaporator fan operatively associated with the second evaporator, a first expansion device operatively associated with the first evaporator and a second expansion device operatively associated with the second evaporator, and a control system for selectively operating the refrigeration system in a cooling mode of operation and an evaporator defrost mode of operation.
  • the control system includes: a first flow control valve disposed in the refrigerant circuit downstream with respect to refrigerant flow of the first and second compressors and upstream with respect to refrigerant flow of the condenser, a second flow control valve disposed in the refrigerant circuit in a suction line to the first compressor interconnecting the plurality of evaporators to a suction inlet of the first compressor, a third flow control valve disposed in a refrigerant line that extends in parallel relationship with respect to refrigerant flow with the first and second compressors from a location in the suction line to the first compressor upstream with respect to refrigerant flow of the second flow control valve, and a fourth flow control valve disposed in a refrigerant line interconnecting a suction line to the second compressor to the suction line to the first compressor at a location in the suction line to the first compressor upstream of the second flow control valve.
  • the refrigeration system may also include a fifth flow control valve disposed in the refrigerant circuit downstream with respect to refrigerant flow of the condenser and upstream with respect to refrigerant flow of the plurality of evaporators, a sixth flow control valve disposed upstream with respect to refrigerant flow of the first evaporator in a refrigerant branch line bypassing the first expansion device, and a seventh flow control valve disposed upstream with respect to refrigerant flow of the second evaporator in a refrigerant branch line bypassing the second expansion device.
  • the control system further includes a controller operative to control the opening and closing of each of the various flow control valves, to control operation of the first compressor and the second compressor, to control operation of the condenser fan, and to control operation of the first evaporator fan and the second evaporator fan.
  • FIG. 1 is a schematic diagram illustrating an exemplary embodiment of a refrigeration system equipped with a hot gas defrost system in accord with the invention
  • FIG. 2 is a table presenting the status of various valves and other components within the refrigeration system shown in FIG. 1 at each of the steps of the hot gas defrost process of the invention
  • FIG. 3 is a schematic diagram of the exemplary embodiment of the refrigeration system shown in FIG. 1 illustrating the status of various valves and other components within the refrigeration system during operation in a cooling mode;
  • FIG. 4 is a schematic diagram of the exemplary embodiment of the refrigeration system shown in FIG. 1 illustrating the status of various valves and other components within the refrigeration system during operation in a first step of the defrost mode;
  • FIG. 5 is a schematic diagram of the exemplary embodiment of the refrigeration system shown in FIG. 1 illustrating the status of various valves and other components within the refrigeration system during operation in a second step of the defrost mode;
  • FIG. 6 is a schematic diagram of the exemplary embodiment of the refrigeration system shown in FIG. 1 illustrating the status of various valves and other components within the refrigeration system during operation in a third step of the defrost mode;
  • FIG. 7 is a schematic diagram of the exemplary embodiment of the refrigeration system shown in FIG. 1 illustrating the status of various valves and other components within the refrigeration system during operation in a fourth step of the defrost mode.
  • FIG. 1 there is depicted an exemplary embodiment of a refrigeration system 100 including a pair of refrigerant vapor compressors 101 and 102, a condenser 120, and a plurality of evaporators 131, 132 and 133, connected in a refrigerant circuit in a conventional manner.
  • a refrigerant vapor compressors 101 and 102 Operatively associated with each of the evaporators 131, 132, 133 is an expansion device 151, 152, 153, respectively, as in conventional practice.
  • Each of the expansion devices 151, 152, 153 may, for example for purposes of illustration but not limitation, be a conventional thermostatic expansion valve.
  • an evaporator fan 141, 142, 143 is operatively associated with each of the evaporators 131, 132, 133, for passing air to be cooled and supplied to a climate-controlled space, such as for example the display zone of a product merchandiser or cold room or the like, through its associated evaporator in heat exchange relationship with refrigerant from the refrigerant circuit, whereby the air is cooled and the refrigerant evaporated.
  • One or more condenser fans 122 are provided in operative association with the condenser 120 for passing ambient air through the condenser in heat exchange relationship with the hot, high pressure refrigerant discharged from the compressors 101, 102, whereby the hot, high pressure refrigerant is cooled and condensed to a high pressure liquid.
  • the refrigeration system 100 also includes a plurality of flow control valves 10, 20, 30, 40, 50, 60-1 and 60-2 disposed at various locations in the refrigerant circuit for selectively opening or closing selected branches of the refrigerant circuit to refrigerant flow therethrough.
  • the first flow control valve 10 is disposed in refrigerant line 2 of the refrigerant circuit downstream with respect to refrigerant flow of the point at which the refrigerant flows from the respective discharge outlets of the first and second compressors 101, 102 combine and upstream with respect to refrigerant flow of the condenser 120.
  • the second flow control valve 20 is disposed in refrigerant suction line 5 upstream with respect to refrigerant flow of the suction inlet to the first compressor 101.
  • the third flow control valve 30 is disposed in refrigerant vapor line 8. As seen in FIG. 1, the refrigerant vapor line 8 extends in parallel relationship with respect to refrigerant flow with the first and second compressors from a location in the suction line 5 to the first compressor 101 upstream with respect to refrigerant flow of the second flow control valve 20.
  • the fourth flow control valve 40 is disposed in suction line 6 that interconnects suction line 5, which is in flow communication with the first compressor 101, in fluid flow communication with suction line 7, which is in flow communication with the second compressor 102.
  • the fifth flow control valve 50 is disposed in refrigerant line 4 that interconnects the refrigerant outlet from the condenser 120 in refrigerant flow communication with the respective refrigerant inlets to the evaporators 131 and 132.
  • the sixth flow control valve 60-1 is disposed in refrigerant line branch 4- 1 intermediate the fifth flow control valve 50 and the evaporator 131.
  • the seventh flow control valve 60-2 is disposed in refrigerant line branch 4-2 intermediate the fifth flow control valve 50 and the evaporator 132.
  • Refrigerant line branch 4-1 provides a flow path bypassing the expansion valve 151 and the refrigerant line branch 4-2 provides a flow path bypassing the expansion valve 152.
  • An additional flow control valve 80 may be disposed in the refrigerant branch line 4-3 upstream of the expansion valve 153.
  • Each of the afore-mentioned flow control valves 10, 20, 30, 40, 50, 60-1, 60-2, 80 may comprise a solenoid valve having an open position in which fluid may pass through the valve and a closed position in which fluid can not flow through the valve.
  • the operation of the refrigeration system 100 may be switched from a cooling mode wherein the evaporators 131 and 132 cool air to be supplied to a temperature controlled space to a defrost mode wherein hot gas is used to defrost the evaporators 131 and 132, by selective positioning of the various valves 10, 20, 30, 40, 50, 60-1 and 60-2, and selective operation of the first compressor 101, the second compressor 102, the evaporator fans 141, 142 and the condenser fan(s) 122, in accord with the status schedule set forth in the table presented in FIG. 2.
  • the refrigeration system 100 may include a controller 200, such as for example for a microprocessor controller, in operative association with each of the afore-mentioned valves, as well as other components of the system including the first and second compressors 101, 102, the evaporator fans 141, 142 and 143, and the condenser fan(s) 122, to selectively control the positioning of the various valves and the operational status of various system components to carry out the hot gas defrost process based upon processing of signals from the defrost sensors 105 operatively associated with the respective evaporators 131 and 132.
  • a controller 200 such as for example for a microprocessor controller, in operative association with each of the afore-mentioned valves, as well as other components of the system including the first and second compressors 101, 102, the evaporator fans 141, 142 and 143, and the condenser fan(s) 122, to selectively control the positioning of the various valves and the operational status
  • both the first compressor 101 and the second compressor 102 are ON, the condenser fan(s) 122 is ON, the evaporator fans 141, 142 are ON, flow control valves 10, 20, 50 are OPEN, and flow control valves 30, 40, 60-1, 60-2 are CLOSED.
  • flow control valve 10 open and flow control valve 30 closed, the hot, high pressure refrigerant vapor discharging from both the first and second compressors 101, 102 passes to the condenser through refrigerant line 2.
  • the first compressor 101 is supplied with suction pressure refrigerant from the evaporators 131, 132 through suction line 5 and the second compressor 102 is supplied with suction pressure refrigerant from the evaporator 133 through suction line 7.
  • the compressors 101, 102 discharge to a common refrigerant line 2 and share the condenser 120 with the first compressor 101, the condenser 120 and the evaporators 131, 132 being connected in refrigerant flow communication in a first refrigerant loop, while the second compressor 102, the condenser 120 and the evaporator 133 being connected in refrigerant flow communication in a second refrigerant loop.
  • step 1 of operation of the refrigeration system 10 in the defrost mode (time tl in FIG. 2), the first compressor 101 is OFF, the second compressor 102 in ON, the evaporator fans 141 and 142 are OFF, the condenser fan 122 is ON, flow control valves 10, 50, 60-1, 60- 2 are open, and flow control valves 20, 30, 40 are closed.
  • the evaporators 131, 132 are flooded with liquid refrigerant from the condenser 120 flowing through refrigerant line 4 and branches 4-1 and 4-2 bypassing the expansion valves 151 and 152, flow control valves 50, 60-1 and 60-2 being in their open position.
  • step 2 of operation of the refrigeration system 10 in the defrost mode hot gas, i.e. hot refrigerant vapor from the second compressor 102, is passed through the evaporators 131, 132 in a reverse direction.
  • the first compressor 101 remains OFF
  • the second compressor 102 is ON
  • the condenser fan(s) 122 and the evaporator fans 141, 142 are OFF
  • flow control valves 10, 20, 40 are closed
  • flow control valves 30, 50, 60-1, 60-2 are OPEN.
  • the hot refrigerant vapor discharging from the second compressor 102 passes through refrigerant vapor line 8 and through the respective heat exchange surface within the evaporators 131, 132 to melt frost and ice accumulated on the evaporator heat exchange surface.
  • the first flow control valve 10 functions as a pressure valve.
  • the flow control valve 60- 1 will be closed.
  • the flow control valve 60-2 will be closed [0026] Referring now to FIGs.
  • step 3 of operation of the refrigeration system 10 in the defrost mode (time t3 in FIG. 2), the flow of hot gas is terminated by positioning the flow control valve 30 in is CLOSED position. Additionally, both the flow control valve 10 and the flow control valve 40 are positioned in their respective OPEN position. The first compressor 101 remains OFF, the second compressor is ON, the condenser fan(s) 122 are turned ON, while the evaporator fans 141, 142 remain OFF. In this step of the defrost process, flow control valves 10, 40, 60-1, 60-2 are OPEN and flow control valves 20, 30, 50 are CLOSED.
  • the second compressor 102 draws refrigerant from all the evaporators, including any refrigerant remaining in the evaporators 131, 132 and the refrigerant line 4 between the closed flow control valve 50 and the evaporators 131, 132.
  • step 4 of operation of the refrigeration system 10 in the defrost mode the refrigeration system 100 is transitioned from the hot gas defrost mode back to the cooling mode.
  • the second compressor 102 remains ON and the first compressor 101 is turned back ON.
  • the condenser fan(s) is ON.
  • the evaporator fans 141, 142 remain OFF for the first few minutes of the step 4 period and then are turned back ON for operation of the evaporators 131, 132 in the cooling mode.
  • the flow control valves 10, 20 are OPEN and the flow control valves 30, 40, 60-1, 60-2 are closed.
  • the flow control valve 50 remains in its CLOSED position for the first few minutes of the step 4 period and then is returned to its OPEN position when the evaporator fans 141, 142 are turned on.
  • the defrost process cycle has been completed and the refrigeration system 100 is returned to the cooling mode with the position status of the flow control valves and the operation status of other system components are all reset for operation of the refrigeration system 100 in the cooling mode.
  • the hot gas defrost process includes four steps: step 1 being liquid flooding of the evaporator(s) to be defrosted; step 2 being hot gas (hot refrigerant vapor) discharge to the evaporator(s) being defrosted; step 3 being drip time and pressure down to suction pressure of the evaporator(s) having been defrosted; and step 4 being cooling mode restarting.
  • step 1 being liquid flooding of the evaporator(s) to be defrosted
  • step 2 being hot gas (hot refrigerant vapor) discharge to the evaporator(s) being defrosted
  • step 3 being drip time and pressure down to suction pressure of the evaporator(s) having been defrosted
  • step 4 being cooling mode restarting.
  • the liquid flooding of the evaporator(s) to be defrosted in the beginning of the defrost process fills the heat exchange coil(s) of the evaporator(s) to be defrosted with warm refrigerant liquid to prepare for the discharging of hot
  • the discharge of hot refrigerant vapor to heat exchange coil(s) of the evaporator(s) being defrosted is terminated when the temperature of the refrigerant line sensed by the defrost sensors 105 has reached a termination temperature.
  • refrigerant is drawn out of the evaporator(s) having been defrosted to return the refrigerant pressure therein to suction pressure and permit drip down of liquid refrigerant to guard against wet running when the refrigeration system 100 is returned to operation in the cooling mode.

Abstract

L'invention porte sur un procédé de dégivrage par gaz chaud, pour dégivrer un évaporateur d'un système de réfrigération. Dans un mode de réalisation donné à titre d'exemple, le procédé de dégivrage par gaz chaud comprend l'étape de noyage d'au moins un évaporateur devant être dégivré par du liquide frigorigène avant la distribution d'une vapeur de fluide frigorigène chaud à l'évaporateur noyé par le liquide. Dans un mode de réalisation donné à titre d'exemple, le procédé de dégivrage par gaz chaud comprend l'étape d'aspiration de la pression de réfrigération à l'intérieur de l'évaporateur lors de l'arrêt de la distribution de la vapeur frigorigène chaude à l'évaporateur qui est dégivré.
PCT/US2009/048850 2008-06-27 2009-06-26 Procédé de dégivrage par gaz chaud WO2009158612A2 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN2009801243671A CN102077039A (zh) 2008-06-27 2009-06-26 热气除霜工艺
EP09771143A EP2313712A2 (fr) 2008-06-27 2009-06-26 Procédé de dégivrage par gaz chaud

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US7623608P 2008-06-27 2008-06-27
US61/076,236 2008-06-27

Publications (2)

Publication Number Publication Date
WO2009158612A2 true WO2009158612A2 (fr) 2009-12-30
WO2009158612A3 WO2009158612A3 (fr) 2010-04-22

Family

ID=41445342

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2009/048850 WO2009158612A2 (fr) 2008-06-27 2009-06-26 Procédé de dégivrage par gaz chaud

Country Status (3)

Country Link
EP (1) EP2313712A2 (fr)
CN (2) CN102865702A (fr)
WO (1) WO2009158612A2 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2487975A (en) * 2011-02-11 2012-08-15 Frigesco Ltd Flash defrost system
US8631666B2 (en) 2008-08-07 2014-01-21 Hill Phoenix, Inc. Modular CO2 refrigeration system
WO2016083858A1 (fr) * 2014-11-24 2016-06-02 Carrier Corporation Systèmes et procédés pour dégivrage libre et positif
US9541311B2 (en) 2010-11-17 2017-01-10 Hill Phoenix, Inc. Cascade refrigeration system with modular ammonia chiller units
US9657977B2 (en) 2010-11-17 2017-05-23 Hill Phoenix, Inc. Cascade refrigeration system with modular ammonia chiller units
US9664424B2 (en) 2010-11-17 2017-05-30 Hill Phoenix, Inc. Cascade refrigeration system with modular ammonia chiller units

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5987916A (en) * 1997-09-19 1999-11-23 Egbert; Mark System for supermarket refrigeration having reduced refrigerant charge
EP1422487A2 (fr) * 2002-11-21 2004-05-26 York Refrigeration APS Dégivrage par gaz chaud pour installations frigorifiques
US20060144060A1 (en) * 2004-12-30 2006-07-06 Birgen Daniel J Heat exchanger liquid refrigerant defrost system

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100186526B1 (ko) * 1996-08-31 1999-10-01 구자홍 히트 펌프의 적상 방지장치

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5987916A (en) * 1997-09-19 1999-11-23 Egbert; Mark System for supermarket refrigeration having reduced refrigerant charge
EP1422487A2 (fr) * 2002-11-21 2004-05-26 York Refrigeration APS Dégivrage par gaz chaud pour installations frigorifiques
US20060144060A1 (en) * 2004-12-30 2006-07-06 Birgen Daniel J Heat exchanger liquid refrigerant defrost system

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8631666B2 (en) 2008-08-07 2014-01-21 Hill Phoenix, Inc. Modular CO2 refrigeration system
US9470435B2 (en) 2008-08-07 2016-10-18 Hill Phoenix, Inc. Modular CO2 refrigeration system
US9541311B2 (en) 2010-11-17 2017-01-10 Hill Phoenix, Inc. Cascade refrigeration system with modular ammonia chiller units
US9657977B2 (en) 2010-11-17 2017-05-23 Hill Phoenix, Inc. Cascade refrigeration system with modular ammonia chiller units
US9664424B2 (en) 2010-11-17 2017-05-30 Hill Phoenix, Inc. Cascade refrigeration system with modular ammonia chiller units
GB2487975A (en) * 2011-02-11 2012-08-15 Frigesco Ltd Flash defrost system
WO2016083858A1 (fr) * 2014-11-24 2016-06-02 Carrier Corporation Systèmes et procédés pour dégivrage libre et positif
RU2672995C1 (ru) * 2014-11-24 2018-11-21 Кэрриер Корпорейшн Система и способ автономного и бесперебойного размораживания
US10823482B2 (en) 2014-11-24 2020-11-03 Carrier Corporation Systems and methods for free and positive defrost

Also Published As

Publication number Publication date
WO2009158612A3 (fr) 2010-04-22
CN102865702A (zh) 2013-01-09
EP2313712A2 (fr) 2011-04-27
CN102077039A (zh) 2011-05-25

Similar Documents

Publication Publication Date Title
US7461515B2 (en) Sequential hot gas defrost method and apparatus
US8011192B2 (en) Method for defrosting an evaporator in a refrigeration circuit
US8695365B2 (en) Apparatus for managing operation of freezing machine
US20120031115A1 (en) Low pressure control for signaling a time delay for ice making cycle start up
EP1029207A2 (fr) Presentoir refrigere a evaporateur modulaire et zone de produits sans degivrage
CN1165734C (zh) 商用制冷系统的运行方法
EP2313712A2 (fr) Procédé de dégivrage par gaz chaud
WO2009028841A2 (fr) Réfrigérateur
EP3502597B1 (fr) Réfrigérateur
US6449967B1 (en) High speed evaporator defrost system
KR100560561B1 (ko) 연속 운전식 쇼케이스
US10823479B2 (en) Multi-evaporator appliance having a multi-directional valve for delivering refrigerant to the evaporators
EP3499157B1 (fr) Réfrigérateur
US20070074523A1 (en) Refrigerating apparatus
CN108700348A (zh) 具有冷冻格室和制冷剂循环系统的制冷器具以及用于运行制冷器具的方法
JP2002188873A (ja) 空気調和機の冷凍装置
US7104083B2 (en) Refrigeration system configuration for air defrost and method
JP4120081B2 (ja) 冷凍装置
JP2003329354A5 (fr)
JP2013204952A (ja) 冷凍サイクル装置
CN111023692A (zh) 运行状态可切换的多温区制冷系统及其控制方法
CN108800750A (zh) 冰箱的控制方法、冰箱及计算机可读存储介质
US20050126198A1 (en) Refrigeration system with reverse flow defrost
JPH0712439A (ja) 二元冷凍装置
JP2002031459A (ja) 冷蔵庫

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 200980124367.1

Country of ref document: CN

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 09771143

Country of ref document: EP

Kind code of ref document: A2

WWE Wipo information: entry into national phase

Ref document number: 2009771143

Country of ref document: EP

NENP Non-entry into the national phase in:

Ref country code: DE