Conditioning apparatus

W. L. McGRATH

CONDITIONING APPARATUS

Jan. 31, 1967

Filed April 26, 1965

3,301,002

Sheets-Sheet 1

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ATTORNEY.

Jan. 31, 1967

3,301,002

W. L. MCGRATH

CONDITIONING APPARATUS

Filed April 26, 1965

Sheets-Sheet ?· &lt;r&gt;

<img file="US3301002A_D0002.tif" />

INVENT01

WILLIAM L. MC GRA

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ATTORNE

Jan. 31, 1967

W. L. McGRATH

3,301,002

CONDITIONING APPARATUS

Filed April 26, 1965

Sheets-Sheet 3

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ATTORNEY.

United States Patent Office _Patented ’X

2

3,301,002

CONDITIONING APPARATUS

William L. McGrath, Syracuse, N.Y., assignor to Carrier Corporation, Syracuse, N.Y., a corporation of Delaware

Filed Apr. 26,1965, Ser. No. 450,833

Claims. (Cl. 62—175)

This invention .relates to a refrigeration apparatus, and more particularly, to a refrigeration apparatus adapted to heat water.

Modification of a refrigeration system of the type having an air cooled outdoor heat exchange coil to enable the system to provide hot water during system operation requires some arrangement for maintaining a minimum condensing temperature under all ambient temperature conditions or the addition of supplementary heating means for the water at relatively high cost. The Joss in system efficiency during most operating conditions from the artificially high condensing temperature imposed on the system increases operating cost of the apparatus. In addition, the vagaries in outdoor conditions and in the demands imposed upon the system necessitates, in most modified systems, that standby or supplemental water heating means be available.

It is a principal object of the present invention to provide a new and improved apparatus for conditioning an enclosure and heating water.

It is a further object of the present invention to provide an apparatus for heating water which includes a relatively small refrigerant compressor and condenser incorporated into a .primary refrigeration system so as to utilize one of the primary refrigeration system heat exchange coils as an evaporator.

It is an object of the present invention to provide a reverse cycle refrigeration system having a second compressor and heat exchange coil interconnected therewith so as to form a second refrigeration system adapted to heat water.

It is an object of the present invention to provide a refrigeration apparatus utilizing a pair of staged compressors with means for insuring an adequate supply of lubricant for each compressor.

, It is an object of the present invention to provide accessory refrigeration apparatus for an air conditioning system which salvages heat rejected by the air conditioning system for the purpose of heating service water.

This invention relates to conditioning apparatus, the combination comprising first refrigerant circuit means for conditioning a first fluid medium, the first circuit means including a compressor, a first heat exchanger, expansion means, and a second heat exchanger; and second refrigerant circuit means adapted to condition a second fluid medium, the second circuit means including a second .compressor, a condenser arranged in heat exchange relation with the second fluid medium, and means connecting the second compressor and the condenser with the first refrigeration circuit means so as to operatively incorporate one of the first and second heat exchangers in the second circuit means.

Other objects and advantages of the present invention will be apparent from the ensuing description and drawings in which:

FIGURE 1 is a diagrammatic view showing a refrigeration system according to the present invention;

FIGURE 2 is a diagrammatic view of a modified form of the refrigeration system shown in FIGURE 1; and

FIGURE 3 is a diagrammatic view showing a reverse cycle refrigeration system according to this invention.

Referring particularly to FIGURE 1 of the drawings, the refrigeration system shown thereat includes compressor 1, heat exchanger 3, condenser coil 2, expansion valve 4 and evaporator coil 6, suitably interconnected in a primary refrigeration circuit. Air to be conditioned is brought into heat exchange relation with evaporator coil 6 by means of fan 7, the conditioned air passing either 5 directly or by means of suitable duct work (not shown) into the area being conditioned. Condenser coil 2 is normally disposed outdoors. Fan 8 brings outdoor air into heat exchange relation with coil 2.

Heat exchanger 3 comprises a closed vessel 9, the IQ upper part of which is interconnected between compressor 1 and coil 2 by refrigerant lines 11, 15 respectively. Heat exchanger coil 16 therein is connected to a suitable source of water to be heated. Refrigerant line 17 connects the lower part of vessel 9 with the system liquid 15 line 23.

Coil 32 of heat exchanger 12 is connected by means of line 10 with the downstream side of coil 2. Line 10 includes a capillary portion 14 serving to meter liquid refrigerant flow between the coils 2, 32 as will be more ap20 parent hereinafter. A pressure controlling device such as a pressure relief valve may be contemplated in place of capillary 14.

Line 18 connects coil 32 with the discharge side of a relatively small compressor 19. Compressors 1,.19 are 25 preferably hermetic reciprocating type compressors. Other suitable compressors such as rotary and nonhermetic type compressors may be contemplated.

The suction side of compressor 19 is connected through lines 20, 21 and separator 22 with coil 2 upstream of line 30 10. The secondary or parasite refrigeration circuit formed includes compressor 19, coil 32, capillary 14, and coil 2 of the primary refrigeration circuit.

Heat exchanger 12 includes a housing 33 connected to the discharge side of circulating .pump 24 by conduit 26. 35 Conduit 30 connects conduit 26 with coil 16 of heat exchanger 3. Pump 24, when energized, circulates water to be heated from storage tank 28 or from the outside source through housing 33 via conduits 26, 27. Check valve 25 prevents direct flow of water to storage tank 40 28 through conduit 29 from the outside source. Heated water is drawn from tank 28 through conduit 31. If desired, an auxiliary heating means such as a resistance type heating element may be provided to supplement heat from heat exchangers 3, 12 to attain a still higher water 45 temperature.

Suitable thermostat controlling means (not shown) are provided for energizing compressor 19, pump 24 and outdoor fan 8 at a predetermined temperature condition of the water in storage tank 28. The relatively hot gaseous 50 refrigerant discharged from compressor 19 passes through line 18 into coil 32, the thermal interchange between coil 32 and the water circulated thereabout by pump 24 heating the water while condensing refrigerant in coil 32. Condensed refrigerant from coil 32 passes by means of ⁵⁵ line 10 and capillary 14 to the primary circuit. Capillary 14 serves to expand the refrigerant in line 10. Gaseous refrigerant returns through line 21, separator 22, and line 20 to the suction side of compressor 19.

Where the primary refrigeration system is simultane⁶⁰ ously operated, a portion of the gaseous refrigerant discharge from compressor 1 is condensed in vessel 9 of heat exchanger 3 by water flowing through coil 16. The warmed water emitted from coil 16 flows through conduits 30, 26 to heat exchanger 12 where further heating 65 thereof is effected by the secondary refrigeration system in the manner explained heretofore. Condensed refrigerant accumulated in the bottom of vessel 9 passes through line 17 to the system liquid line 23 where it mixes with refrigerant from condenser coil 2. Gaseous 7° refrigerant in vessel 9 flows through line 15 to coil 2 where a portion thereof passes through lines 21, 20 to

3,301,002 ³ the suction side of compressor 19, the remainder flowing through coil 2, expansion valve 4, and evaporator coil 6 to compressor 1 in the usual manner. By extracting refrigerant from the primary circuit coil 2, applicant is able to effectively desuperheat the refrigerant for use in the secondary refrigeration circuit.

Where the primary refrigeration system is inoperative, the flow of refrigerant through condenser coil 2 between lines 10, 21 is reversed from that occurring during operation of the primary refrigeration system. Condenser coil 2 in this circumstance functions as the evaporator for the secondary circuit.

Heated water is stored in tank 28 until such time as demand therefor is made. Pressure available from the source of water forces the heated water from tank 28 upon opening of conduit 31.

Line 60 connects the lower portion of separator 22 with the sump of compressor 19. Line 61, joined to separator 22 at a selected lubricant level and having a capillary portion 62, is connected to the suction side of compressor 1.

Lubricant entrained in the stream of refrigerant flowing through conduits 20, 21 to compressor 19 accumulates in the lower portion of separator 22 from whence it may flow through line 60 to the sump of compressor 19 thereby insuring an adequate supply of lubricant for compressor 19. Should the lubricant level in separator 22 rise above line 61, the lubricant is drawn through line 61 and capillary 62 into the stream of suction gas flowing to compressor 1. The lubricant entrained in the refrigerant gas stream may, during the compression process, deposit in the crankcase of either compressor 1 or compressor 19, or in the lower portion of separator 22 as explained heretofore.

Where only one of the compressors 1, 19 is operated, no substantial transfer of lubricant from one compressor to the other transpires. If desired, the speed of fan 8 may be varied to maintain a predetermined minimum pressure in coil 2, in a manner well-known in the art.

Referring to FIGURE 2 of the drawings wherein like numerals identify like parts, line 21 is arranged to draw refrigerant from the primary refrigeration system upstream of condenser coil 2. To effect the desired desuperheating of the refrigerant prior to the introduction of the refrigerant into compressor 19 and to extract heat at the temperature of coil 2, a portion 26' of line 20 is disposed in housing 33 of heat exchanger 12 in heat exchange relation with the water to be heated. The arrangement of the remaining portions of the system of the FIGURE 2 embodiment and the operation and function thereof is the same as that described heretofore.

Referring particularly to FIGURE 3 of the drawings, an arrangement for heating water by means of a secondary refrigeration circuit which utilizes a portion of a reverse cycle (heat pump) refrigeration circuit is therein shown. The primary refrigeration circuit includes compressor 65, reversing valve 66, indoor coil 67, expansion valves 68, 69, and outdoor coil 70 suitably coupled together. Indoor and outdoor fans 72, 73 are provided.

Where reversing valve 66 is disposed in the position shown in solid line in FIGURE 3 of the drawings, the system, upon energization of compressor 65, cools, the refrigerant discharged from compressor 65 being routed by reversing valve 66 through outdoor coil 70, expansion valve 68 into indoor coil 67, the refrigerant returning through reversing valve 66 to the suction side of compressor 65. During the cooling cycle check valve 74 bypasses refrigerant expansion valve 69.

When reversing valve 66 is disposed in the dotted line position shown in FIGURE 3 of the drawings, refrigerant discharged in compressor 65 is routed by valve 66 through indoor coil 67, expansion valve 69 into outdoor coil 70, the refrigerant returning through valve 66 to the suction side of compressor 65. Check valve 75 bypasses expansion valve 69. The system accordingly heats.

Heat exchanger 78 includes a coil 88 connected by line 79 with closed refrigerant separating vessel 76. Line 77 connects the upper portion of vessel 76 with discharge line 80 of compressor 65. Line 86 connects the lower portion of vessel 76 with the primary refrigeration system liquid line 98. Relief valve 81 in line 79 permits flow of refrigerant when pressures in coil 88 exceed pressures in discharge line 80· by a predetermined amount.

Line 82 connects coil 88 to the discharge side of a relatively small compressor 83. Lines 84, 85 connect the suction side of compressor 83 through separator 22' with dis charge line 80 of compressor 65. Line 87 joins line 85 with the primary refrigeration circuit liquid line 98. Expansion valve 90 in line 87 regulates communication between lines 87, 85 in response to thermal conditions at the suction side of compressor 83.

Pump 91 having an inlet side connected with a suitable source of water, circulates water through conduit 92, housing 89 of heat exchanger 78, and conduit 94 to •storage tank 93. Conduit 97 connects the inlet side of pump 91 with tank 93. Check valve 95 prevents direct flow of water from the source of water through conduit 97 into tank 93.

Suitable thermostat controlling means (not shown) are provided for energizing compressor 83, pump 91, and outdoor fan 73 at a predetermined temperature condition of the water in storage tank 93. Compressor 83 discharges relatively hot gaseous refrigerant through line 82 into coil 88. The thermal interchange between coil 88 and the water disposed thereabout heats the water while condensing refrigerant in coil 88. Refrigerant from coil 88 flows through valve 81 and line 79 into the vessel 76, gaseous refrigerant in vessel 76 passing through line 77 into the stream of gas discharged from compressor 65. Liquid refrigerant in vessel 76 passes through line 86 to the system liquid line 98. A portion of the gas discharging from compressor 65 passes through line 84, separator 22', and line 85 to compressor 83. Thermal expansion valve 99, responsive to the thermal conditions of the refrigerant in line 85, serves to desuperheat refrigerant flowing through line 85 to the suction side of compressor 83 by mixing controlled amounts of relatively high pressure liquid refrigerant from the primary circuit with the gaseous refrigerant in line 85.

The secondary refrigeration system may be operated to heat water while the primary refrigeration system is inoperative. Where the primary refrigeration circuit is inoperative, reversing valve 66 is in the cooling cycle position. Gaseous refrigerant in vessel 76 passes through lines 77, 84, separator 22' and line 85 to the suction side of compressor 83. Liquid refrigerant in vessel 76 passes through lines 86, 98, expansion valve 69, outdoor coil 70, reversing valve 66, into lines 84, 85 and the suction side of the compressor 83 as described above.

The lubricant controlling arrangement comprised of separator 22', lubricant lines 60', 61' an capillary 62' is similar in operation to that described in conjunction with FIGURES 1 and 2.

While I have described preferred embodiments of the present invention, it is understood that this invention may be otherwise embodied within the scope of the following claims.