Heat pump systems and methods incorporating subcoolers for conditioning air

• US 5,689,962 A
• Filed: 05/24/1996
• Issued: 11/25/1997
• Est. Priority Date: 05/24/1996
• Status: Expired due to Fees

• Current Assignee: Store Heat and Produce Energy Incorporated (AES Corporation)
• Original Assignee: Store Heat and Produce Energy Incorporated (AES Corporation)
• Inventors: Rafalovich, Alexander P.
• Primary Examiner(s): Sollecito, John M.
• Application Number:
  US08/653,673
• Time in Patent Office: 550 Days
• Field of Search: 62/89, 62/90, 62/113, 62/173, 62/324.1, 62/324.5, 62/325, 62/404, 62/428, 62/506, 62/513
• US Class Current: 62/90
• CPC Class Codes: F24F 3/153 with subsequent heating, i.e. with the air, given the required humidity in the central station, passing a heating element to achieve the required temperature
• CPC Class Codes: F25B 13/00 Compression machines, plants or systems, with reversible cycle defrosting cycles F25B47/02
• CPC Class Codes: F25B 2313/023 using multiple indoor units
• CPC Class Codes: F25B 2400/22 Refrigeration systems for supermarkets
• CPC Class Codes: F25B 5/02 arranged in parallel

Abstract

Described are heat pump systems and methods for conditioning air, in which air is dehumidified including the steps of passage over an evaporator to cool and dehumidify the air, followed by passage over a subcooler to heat the air prior to passage into a space to be conditioned. Also described are heat pump systems and methods for conditioning air, in which air is heated by passage over a subcooler followed by passage over a condenser. The methods and systems are readily implemented and highly effective in improving system capacity.

Claims

1. A heat pump and air conditioning system for conditioning air including dehumidification, comprising:

a compressor for compressing refrigerant;

a condenser for condensing refrigerant after exiting the compressor and transferring heat from the refrigerant to a heat sink;

a pressure reduction device for expanding refrigerant after exiting said condenser to a predetermined pressure above ana evaporating pressure of the refrigerant in the system;

at least one subcooler for extracting heat from condensed refrigerant after exiting the pressure reduction device;

at least one evaporator for evaporating liquid refrigerant after exiting the subcooler;

means for moving air to be conditioned first against said at least one evaporator and then against said at least one subcooler; and

a fluid path for returning refrigerant after exiting said at least one evaporator to said compressor.

2. A heat pump for conditioning air, comprising:

a compressor for compressing refrigerant;

an outdoor heat exchanger which functions as a condenser in a cooling mode of the heat pump, and as an evaporator in a heating mode of the heat pump;

first and second indoor heat exchangers, the first indoor heat exchanger functioning as a condenser in the heating mode and the second indoor heat exchanger functioning as a subcooler in the heating mode;

at least one fan operable in the heating mode to move air to be conditioned through said second indoor heat exchanger while functioning as a subcooler and then through said first heat exchanger while functioning as a condenser.

3. A heat pump for conditioning air including dehumidification, comprising:

a compressor for compressing refrigerant;

an outdoor heat exchanger which functions as a condenser in a cooling mode of the heat pump and as an evaporator in a heating mode of the heat pump;

first and second indoor heat exchangers connected in series, the first indoor heat exchanger functioning as a condenser and the second indoor heat exchanger functioning as a subcooler in said heating mode; and

, the first indoor heat exchanger functioning as a subcooler and the second indoor heat exchanger functioning as an evaporator in said cooling mode;

at least one fan operable to move air to be conditioned through said second indoor heat exchanger and then through said first heat exchanger.

4. A method for dehumidifying air, comprising:

condensing refrigerant in a condenser;

expanding refrigerant after exiting the condenser in a pressure reduction device to a predetermined pressure above an evaporating pressure of the refrigerant;

subcooling refrigerant after exiting the pressure reduction device in a subcooler;

evaporating refrigerant after exiting the subcooler in an evaporator;

passing a forced stream of the air against said evaporator wherein it forms a cooled and dehumidified air stream; and

passing the cooled and dehumidified air stream against the subcooler wherein it is heated.

5. A method for forming heated air for conditioning a space, comprising:

condensing refrigerant in a condenser;

subcooling refrigerant after exiting the condenser in a subcooler;

passing a forced stream of air against said subcooler to form a first heated air stream; and

passing the first heated air stream against the condenser to form a second heated air stream.

6. A method for conditioning air, comprising:

(i) in a cooling mode;

condensing refrigerant in a condenser;

subcooling the refrigerant after exiting the condenser in a subcooler;

evaporating the refrigerant after exiting the subcooler in an evaporator;

passing a forced air stream first against the evaporator and then against the subcooler, wherein it is cooled and dehumidified by the evaporator and then heated by the subcooler; and

(ii) in a heating mode;

condensing refrigerant in a condenser;

subcooling the refrigerant after exiting the condenser in a subcooler; and

passing a forced air stream first against the subcooler and then against the condenser to form a heated air stream.

7. A system for conditioning air operable in a heating mode and a cooling mode, the system comprising:

a cooling loop including;

a condenser for condensing refrigerant;

a subcooler for subcooling refrigerant after exiting the condenser;

an evaporator for evaporating refrigerant after exiting the subcooler;

means for moving air to be conditioned in the cooling mode first against the evaporator and then against the subcooler, wherein it is cooled and dehumidified by the evaporator and then heated by the subcooler;

a heating loop including;

a condenser for condensing refrigerant;

a subcooler for subcooling refrigerant after exiting the condenser;

means for moving air first against the subcooler and then against the condenser to form a heated air stream.