US20030213253A1 - Air conditioner mist applicator - Google Patents

Air conditioner mist applicator Download PDF

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Publication number
US20030213253A1
US20030213253A1 US10/147,542 US14754202A US2003213253A1 US 20030213253 A1 US20030213253 A1 US 20030213253A1 US 14754202 A US14754202 A US 14754202A US 2003213253 A1 US2003213253 A1 US 2003213253A1
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Prior art keywords
valve
mist
refrigerant
water
air conditioner
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US10/147,542
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US6658872B1 (en
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Dennis James
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F1/00Room units for air-conditioning, e.g. separate or self-contained units or units receiving primary air from a central station
    • F24F1/06Separate outdoor units, e.g. outdoor unit to be linked to a separate room comprising a compressor and a heat exchanger
    • F24F1/42Separate outdoor units, e.g. outdoor unit to be linked to a separate room comprising a compressor and a heat exchanger characterised by the use of the condensate, e.g. for enhanced cooling
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28DHEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D5/00Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, using the cooling effect of natural or forced evaporation
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F13/00Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
    • F24F13/22Means for preventing condensation or evacuating condensate
    • F24F13/222Means for preventing condensation or evacuating condensate for evacuating condensate
    • F24F2013/225Means for preventing condensation or evacuating condensate for evacuating condensate by evaporating the condensate in the cooling medium, e.g. in air flow from the condenser
    • 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
    • F25B2339/00Details of evaporators; Details of condensers
    • F25B2339/04Details of condensers
    • F25B2339/041Details of condensers of evaporative condensers
    • 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, plants or systems
    • F25B49/027Condenser control arrangements

Definitions

  • Prior art devices have attempted to measure some indicator that the condenser is running such as vibration, heat or airflow to indicate a need for mist.
  • the problem is that these are not true measures of the need for mist.
  • the true measure of the need for mist cooling is the head pressure of the refrigerant leaving the condenser to return to the evaporator. This head pressure is a true indicator of the need for mist. As the head pressure increases past a designed pressure the unit will lose efficiency. Misting the condenser will reduce the head pressure.
  • Another problem with prior art units is that they introduce a device with components that the air conditioner service technician is not familiar with.
  • the present invention solves the limitations of the prior art devices.
  • the current invention provides an air conditioner condenser mist device activated only as the head pressure in the coolant leaving the condenser exceeds a certain preset level.
  • the current device provides a mister that uses valves and systems with which most air conditioner service people are already familiar.
  • the current invention provides a reliable system with a minimum of moving parts.
  • FIG. 1 Shows a schematic system for applying mist to an air conditioner condenser unit
  • FIG. 2 Shows a view of the system installed on a condenser unit
  • FIG. 1 shows a basic schematic view of the mist system ( 1 ).
  • FIG. 2 gives an external view of the appearance of the device at the condenser ( 2 ).
  • a pressure activated water control valve ( 10 ) supplies water to a mist nozzle ( 20 ) through water line ( 30 ).
  • the mist nozzle supplies water at a rate of about one gallon per hour at 100 PSI water pressure.
  • the water control valve ( 10 ) receives a signal indicating high head pressure in the high pressure side ( 4 ) of the refrigerant system from a “tee” adapter ( 40 ) tied in to the existing service valve connection ( 42 ) present on most air conditioners.
  • line ( 44 ) is constantly pressurized at a level equal to the head pressure in the refrigerant high pressure side ( 4 ) from the condenser ( 2 ).
  • Line ( 60 ) is the low pressure return line to the condenser ( 2 ) from the evaporator ( 8 ) inside the conditioned space.
  • Water is supplied from a water line tap ( 70 ) attached to a water line ( 72 ).
  • a water line ( 32 ) from the tap ( 70 ) supplies water through a filter ( 80 ) to the line ( 34 ) which provides water to the water valve ( 10 ).
  • the water control valve ( 10 ) is the main part of the mist system ( 1 ). It is connected to the high pressure line ( 4 ) from the condenser ( 2 ) to the evaporator ( 8 ). The head pressure controls the water valve ( 10 ). When the high pressure goes over a set point the valve ( 10 ) will open and let water from the tap ( 70 ) through to the mist nozzles ( 20 ).
  • the “set point” must be set by a technician and will vary depending upon the type of air conditioner, environmental conditions and desired operation. The system must be balanced to maximize efficiency but to minimize any risk of unit freeze up and to minimize the amount of water on the ground.
  • the mist nozzles ( 20 ) are mounted around the top of the condenser unit as shown in FIG. 2.
  • the condenser unit fan (not shown) will pull the mist through the condenser coils where it will wet the surface of the condenser coils and fins. Once wet, the water evaporating off the coils will speed the rate of heat transfer to the environment, improving the cycle efficiency and reducing wear on the air conditioner.
  • the water filter ( 80 ) is of the type used to take minerals such as calcium out of water.
  • a 3 micron filter unit is widely available commercially. Hard water would cause the nozzles ( 20 ) to plug up over time, so the unit will work with less maintenance with a filter.
  • the water control valve is one already in use in water cooled ice makers and air conditioners.
  • the tap ( 70 ) and filter ( 80 ) are units already commonly in use with the water supply to household icemakers.

Abstract

A mist system for use in conjunction with a normally air cooled air conditioner condenser. The mist system provides cooling water to the coils and fins of the condenser to improve efficiency. Misting is normally off but comes on in response to pressure in the high pressure supply line from the condenser rising above a pre-set head pressure level.

Description

    BACKGROUND OF THE INVENTION
  • In air conditioner technology it is desirable to run the air conditioner unit as efficiently as possible both to save on energy and to save wear and tear on the air conditioner. One way to improve efficiency is to spray a fine mist of water on the evaporative condenser. The condenser of the air conditioner is often located outside of the building or space being conditioned. The idea is to improve heat transfer from the condenser by wetting the surface of the metal pipes and fins that make up the condensers heat transfer system. [0001]
  • A number of attempts have been made to perfect this type of wetting system. U.S. Pat. No. 4,685,308 to Welker et al discloses one such system. Water for the misters is usually supplied from a tap. Typically something then trips a valve to activate the mist when the A/C unit is running. In the case of Welker the system detects a high temperature to initiate mist flow. The idea is to supply water in the form of mist only when it is needed and to avoid excessive flow when not needed. Misting the condenser when it is not running hot can result in the condenser freezing up, which reduces efficiency to near zero and can ruin the unit. Excess water also results in waste and undesirable amounts of water on the ground around the unit. [0002]
  • Prior art devices have attempted to measure some indicator that the condenser is running such as vibration, heat or airflow to indicate a need for mist. The problem is that these are not true measures of the need for mist. The true measure of the need for mist cooling is the head pressure of the refrigerant leaving the condenser to return to the evaporator. This head pressure is a true indicator of the need for mist. As the head pressure increases past a designed pressure the unit will lose efficiency. Misting the condenser will reduce the head pressure. Another problem with prior art units is that they introduce a device with components that the air conditioner service technician is not familiar with. [0003]
  • SUMMARY OF THE INVENTION
  • The present invention solves the limitations of the prior art devices. The current invention provides an air conditioner condenser mist device activated only as the head pressure in the coolant leaving the condenser exceeds a certain preset level. The current device provides a mister that uses valves and systems with which most air conditioner service people are already familiar. The current invention provides a reliable system with a minimum of moving parts.[0004]
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 Shows a schematic system for applying mist to an air conditioner condenser unit [0005]
  • FIG. 2 Shows a view of the system installed on a condenser unit[0006]
  • DETAILED DESCRIPTION OF THE DEVICE
  • FIG. 1 shows a basic schematic view of the mist system ([0007] 1). FIG. 2 gives an external view of the appearance of the device at the condenser (2). Referring to FIGS. 1 and 2, a pressure activated water control valve (10) supplies water to a mist nozzle (20) through water line (30). The mist nozzle supplies water at a rate of about one gallon per hour at 100 PSI water pressure. The water control valve (10) receives a signal indicating high head pressure in the high pressure side (4) of the refrigerant system from a “tee” adapter (40) tied in to the existing service valve connection (42) present on most air conditioners. Thus line (44) is constantly pressurized at a level equal to the head pressure in the refrigerant high pressure side (4) from the condenser (2). Line (60) is the low pressure return line to the condenser (2) from the evaporator (8) inside the conditioned space.
  • Water is supplied from a water line tap ([0008] 70) attached to a water line (72). A water line (32) from the tap (70) supplies water through a filter (80) to the line (34) which provides water to the water valve (10).
  • In operation the water control valve ([0009] 10) is the main part of the mist system (1). It is connected to the high pressure line (4) from the condenser (2) to the evaporator (8). The head pressure controls the water valve (10). When the high pressure goes over a set point the valve (10) will open and let water from the tap (70) through to the mist nozzles (20). The “set point” must be set by a technician and will vary depending upon the type of air conditioner, environmental conditions and desired operation. The system must be balanced to maximize efficiency but to minimize any risk of unit freeze up and to minimize the amount of water on the ground.
  • The mist nozzles ([0010] 20) are mounted around the top of the condenser unit as shown in FIG. 2. The condenser unit fan (not shown) will pull the mist through the condenser coils where it will wet the surface of the condenser coils and fins. Once wet, the water evaporating off the coils will speed the rate of heat transfer to the environment, improving the cycle efficiency and reducing wear on the air conditioner.
  • The water filter ([0011] 80) is of the type used to take minerals such as calcium out of water. A 3 micron filter unit is widely available commercially. Hard water would cause the nozzles (20) to plug up over time, so the unit will work with less maintenance with a filter.
  • Most of the devices used in the construction of the mist system are either simple components or items with which the air conditioning technician will already be familiar. The water control valve is one already in use in water cooled ice makers and air conditioners. The tap ([0012] 70) and filter (80) are units already commonly in use with the water supply to household icemakers.

Claims (5)

1. A mist system for use in combination with an air conditioner compressor normally cooled by a flow of air, said mist system comprising:
a plurality of mist nozzles mounted on said air conditioner compressor,
a valve in fluid communication with said nozzles,
a high pressure line supplying refrigerant from said compressor to an evaporator,
said valve receiving a portion of said refrigerant through a line,
a tap for supplying water to said valve and said valve opening in response to receiving said refrigerant at a pre-set pressure level such that water can flow from said tap through said valve and to said nozzles when pressure in the high pressure supply line exceeds the pre-set pressure level.
2. The mist system of claim 1 wherein said water from said tap flows through a filter prior to entering said valve.
3. The mist system of claim 1 wherein the valve is normally closed.
4. A mist system for use in combination with an air conditioner compressor normally cooled by a flow of air, said mist system 1
At least one mist nozzles mounted on said air conditioner compressor,
a valve in fluid communication with said at least one nozzle,
a high pressure line supplying refrigerant from said compressor to an evaporator,
said valve receiving a portion of said refrigerant through a line,
a tap for supplying water to said valve and said valve opening in response to receiving said refrigerant at a pre-set pressure level such that water can flow from said tap through said valve and to said at least one nozzle when pressure in the high pressure refrigerant line exceeds the pre-set pressure level.
5. A mist system for use in combination with an air conditioner compressor normally cooled by a flow of air, said mist system comprising:
a plurality of mist nozzles mounted on said air conditioner compressor,
a valve in fluid communication with said nozzles,
a high pressure line supplying refrigerant from said compressor to an evaporator,
said valve receiving pressure from said refrigerant,
a tap for supplying water to said valve and said valve opening in response to receiving said refrigerant at a pre-set pressure level such that water can flow from said tap through said valve and to said nozzles when pressure in the high pressure refrigerant line exceeds the pre-set pressure level.
US10/147,542 2002-05-16 2002-05-16 Air conditioner mist applicator Expired - Fee Related US6658872B1 (en)

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7021070B2 (en) 2002-02-08 2006-04-04 Tim Allan Nygaard Jensen System and method for cooling air
US20080034776A1 (en) * 2005-08-09 2008-02-14 Tim Allan Nygaard Jensen Prefilter System for Heat Transfer Unit and Method
US7441412B2 (en) 2005-01-26 2008-10-28 Tim Allan Nygaard Jensen Heat transfer system and method
US20110192172A1 (en) * 2010-01-07 2011-08-11 Moises Aguirre Delacruz Temperature conditioning system method to optimize vaporization applied to cooling system
US20110232859A1 (en) * 2008-08-28 2011-09-29 Ac Research Labs Air Conditioner Cooling Device
US20130042995A1 (en) * 2011-08-15 2013-02-21 Richard D. Townsend ACEnergySaver (AC Energy Saver)
US20130139534A1 (en) * 2010-08-16 2013-06-06 Huawei Technologies Co., Ltd. Energy-saving device for air conditioner outdoor unit and energy-saving method thereof
US20140263765A1 (en) * 2011-09-30 2014-09-18 Daikin Industries, Ltd. Outdoor unit for air conditioning device
US20140331703A1 (en) * 2013-05-09 2014-11-13 Dennis Barry LaConte Air-conditioning system
WO2018013910A1 (en) * 2016-07-15 2018-01-18 Wal-Mart Stores, Inc. Air-cooled ammonia refrigeration systems and methods
US10502465B2 (en) 2016-07-15 2019-12-10 Walmart Apollo, Llc Air-cooled ammonia refrigeration systems and methods

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6892552B2 (en) 2003-01-06 2005-05-17 Physics Support Services, Llc System and method for cooling air inhaled by air conditioning housing unit
US7234316B2 (en) * 2004-08-23 2007-06-26 Taiwan Fluorescent Lamp Co., Ltd. Modularized high efficiency cooling device in a cooling mechanism
US7284742B1 (en) 2005-09-12 2007-10-23 Lem Rachels Flow control valve
US20080104980A1 (en) * 2006-11-06 2008-05-08 Payton Keith A Misting system for air conditioning compressor
US20100200211A1 (en) * 2009-02-10 2010-08-12 Ali Erturk Green Cooling System For Outdoor Areas, Heat Transfer Units, and High Pressure Washing Utilizing a High Pressure Pump and a Multi-zone Controller
WO2010105198A1 (en) * 2009-03-12 2010-09-16 Tonerhead, Inc. Mist dispersal system for air conditioners
US8156749B1 (en) 2009-09-21 2012-04-17 Orten Philip A Portable sprinkler system
US7878012B1 (en) 2009-09-21 2011-02-01 Orten Philip A Portable sprinkler system
CN108954778A (en) * 2018-06-28 2018-12-07 清远市元信智能科技有限公司 A kind of energy-saving air conditioning
JP7207202B2 (en) 2019-06-28 2023-01-18 トヨタ自動車株式会社 vehicle
JP7211290B2 (en) * 2019-06-28 2023-01-24 トヨタ自動車株式会社 In-vehicle air conditioner
JP2021006441A (en) 2019-06-28 2021-01-21 トヨタ自動車株式会社 On-vehicle air conditioner

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4193269A (en) * 1978-08-14 1980-03-18 Carrier Corporation Apparatus for supplying a cooling liquid to a condenser of a refrigeration unit
US4685308A (en) 1984-07-02 1987-08-11 Welker Mark L Temperature responsive cooling apparatus

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7021070B2 (en) 2002-02-08 2006-04-04 Tim Allan Nygaard Jensen System and method for cooling air
US7441412B2 (en) 2005-01-26 2008-10-28 Tim Allan Nygaard Jensen Heat transfer system and method
US20090049846A1 (en) * 2005-01-26 2009-02-26 Tim Allan Nygaard Jensen Heat Transfer System and Method
US7757499B2 (en) 2005-01-26 2010-07-20 Tim Allan Nygaard Jensen Heat transfer system and method
US20080034776A1 (en) * 2005-08-09 2008-02-14 Tim Allan Nygaard Jensen Prefilter System for Heat Transfer Unit and Method
US7805953B2 (en) 2005-08-09 2010-10-05 Tim Allan Nygaard Jensen Prefilter system for heat transfer unit and method
US20110232859A1 (en) * 2008-08-28 2011-09-29 Ac Research Labs Air Conditioner Cooling Device
US20110192172A1 (en) * 2010-01-07 2011-08-11 Moises Aguirre Delacruz Temperature conditioning system method to optimize vaporization applied to cooling system
US20130139534A1 (en) * 2010-08-16 2013-06-06 Huawei Technologies Co., Ltd. Energy-saving device for air conditioner outdoor unit and energy-saving method thereof
WO2012093944A1 (en) * 2011-01-07 2012-07-12 Delacruz Moises A Method to optimize vaporization applied to cooling processes
US20130042995A1 (en) * 2011-08-15 2013-02-21 Richard D. Townsend ACEnergySaver (AC Energy Saver)
US20140263765A1 (en) * 2011-09-30 2014-09-18 Daikin Industries, Ltd. Outdoor unit for air conditioning device
US20140331703A1 (en) * 2013-05-09 2014-11-13 Dennis Barry LaConte Air-conditioning system
WO2018013910A1 (en) * 2016-07-15 2018-01-18 Wal-Mart Stores, Inc. Air-cooled ammonia refrigeration systems and methods
GB2567350A (en) * 2016-07-15 2019-04-10 Walmart Apollo Llc Air-cooled ammonia refrigeration systems and methods
GB2567350B (en) * 2016-07-15 2019-09-11 Walmart Apollo Llc Air-cooled ammonia refrigeration systems and a method of refrigeration using an air-cooled ammonia refrigeration system
US10502465B2 (en) 2016-07-15 2019-12-10 Walmart Apollo, Llc Air-cooled ammonia refrigeration systems and methods
US10670307B2 (en) 2016-07-15 2020-06-02 Walmart Apollo, Llc Air-cooled ammonia refrigeration systems and methods
US11226143B2 (en) 2016-07-15 2022-01-18 Walmart Apollo, Llc Air-cooled ammonia refrigeration systems and methods
US11466905B2 (en) 2016-07-15 2022-10-11 Walmart Apollo, Llc Air-cooled ammonia refrigeration systems and methods

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