Abstract: A refrigerator comprising a freezing compartment and a refrigerating compartment which refrigerator is provided with a primary refrigerating system containing a refrigerant with a primary evaporator disposed in the freezing compartment, and a secondary refrigerating system which also contains a refrigerant with a secondary evaporator disposed in the refrigerating compartment, and a secondary condensor which is in heat-exchanging contact with the primary evaporator, which condensor has a condensation wall on whose surface the refrigerant condenses during operation, means being provided for varying the available condensation wall area, so as to control the temperature of the secondary evaporator.

Abstract: Apparatus for satisfying heating and cooling demands including a cooling circuit including a mechanical refrigeration unit having a low pressure side and a high pressure side, a heating circuit including a booster compressor for drawing and further compressing refrigerant from the high pressure side of the refrigeration unit, and a heat reclaiming condenser for passing the further compressed refrigerant vapor in heat transfer relation with a heat transfer fluid to heat the fluid and condense the refrigerant vapor. Also disclosed is a control for reducing the vapor flow rate through the booster compressor when the pressure in the high pressure side of the refrigeration unit falls below a predetermined value.

Abstract: Heat transfer systems utilizing the standard vapor/compression refrigeration cycle with commonly available refrigerant fluids are disclosed. The embodiments disclosed provide switching means for selective use of the equipment for cooling or for heating in preferred form. In some embodiments, only the heating or only the cooling capability of a system is utilized. Common to the embodiments is a system for pressurizing the refrigerant fluid utilizing a heat source such as a solar collector, waste heat from a generator, automobile engine or other power plant, or even a small gas or electrical heater or the like. Equipment including a venturi device for drawing refrigerant at low pressure through an evaporator for cooling purposes and for extraction of heat from the atmosphere for heating purposes is also disclosed.

Abstract: An improved load balancing control circuit for at least three electric motor-driven centrifugal refrigerant compressors comprises a current transformer secondary 90', 91', 92' and a respective load resistor 93', 95', 97' in series to form the legs of a circuit in which the legs are connected in a delta, each leg having a shorting switch 110', 111', 112' connected across it, and a balancing resistance network including balancing resistors 94', 96', 98' are connected in a wye circuit with the delta circuit.

Abstract: Apparatus is described for maintaining refrigerant temperature at or below a predetermined level by providing a combination of a primary chiller cooled by a primary mechanical refrigeration system and a series-connected back-up liquid nitrogen-cooled chiller which would operate only if the primary mechanical refrigeration system is incapable of providing the desired refrigerant temperature.

Abstract: An optimization system for switching between plural parallel connected chillers in a refrigeration system is disclosed which system establishes optimized changeover criteria based upon the design refrigerant head for the chillers, the minimum refrigerant head for the chillers, the capacity of the chillers at design head and the capacity of the chillers at minimum head, and which system, using these criteria, calculates optimized switchover capacity as a function of the present actual refrigerant head. The system then compares the optimized switchover capacity to the present building load and, if the capacity is insufficient to meet the building load, an additional chiller is switched in and, if the optimized switchover capacity is greater than the building load and more than one chiller is operating, one of the chillers is disconnected.

Abstract: A compression module in the form of a four cylinder reciprocating piston compressor, having two cylinders for each of two cylinder heads, is interconnected by conduits and manifolds which in turn incorporate solenoid operated control valves and check valves to provide five pressure levels for the compressor cylinders to remove automatically intermediate pressure refrigerant and to return intermediate pressure refrigerant, to achieve single or multiple cylinder compressor staging, and effect unloading of one head by cutting off low pressure suction return to that compressor head.

Abstract: A closed cycle, multiple compressor, multiple evaporator, refrigeration system of the type particularly adapted to supermarket applications having a common condenser, a multiplicity of refrigerated fixtures with associated evaporators for cooling, all operating at the same temperature and pressure, all discharging into a common compressor suction header and a series of parallel compressors pumping from the common suction header to the condenser, together with a second set of refrigerated fixtures having evaporators operating at a lower pressure than that of the first multiplicity of evaporators, discharging into a second, lower pressure, suction header, from where its effluent refrigerant is pumped by a second compressor system back to the common condenser.

Abstract: Two air conditioning compressors connected in parallel supply an evaporator suitably valved for operation at full capacity with both compressors for maximum normal comfort cooling, for operation at half capacity with one of the compressors for half capacity normal comfort cooling, and for operation at three-quarter capacity with both compressors for maximum dehumidification of the treated air without frosting the evaporator. Waste heat from a refrigerant compressor may be used to reheat the air during the dehumidification operation.

Abstract: A refrigeration system including multiple parallel compressors for maintaining evaporator suction pressures within preselected ranges, said compressors being sequentially and cyclically operative through control switch means responsive to preselected upper and lower refrigerant suction pressures, a fluidic time delay system for operating the pressure responsive switch means comprising restrictor means interposed between the common suction header for the compressors and the pressure responsive switch means therefor to restrict refrigerant fluid flow to the pressure switches upon increases in suction header pressure, and unidirectional flow means for providing unrestricted reduction of the pressure acting on the switch means upon relative decreases in suction header pressure.

Abstract: An air conditioning system has an evaporative cooler and a refrigerated cooler connected to a common duct connecting both of the coolers to a cooled space. A space thermostat senses space temperature of the cooled space and initiates cooling responsive thereto. A cooler selection control selects one of the coolers for cooling the cooled space responsive to the relative humidity and temperature of air outside the cooled space. The selection control delays starting of the refrigerated cooler a cool down period after the initiation of cooling. With the evaporative cooler employed in a system with, or in a system without, the refrigerated cooler, the evaporative fan is started a wetting period after the starting of the evaporative pump of the evaporative cooler to wet the evaporative pads. Additionally an exhaust vent opens when the evaporative fan of the evaporative cooler is operating and closes when the evaporative fan is stopped.

Abstract: A device for controlling a single variable capacity compressor, or multiple variable capacity compressors in either parallel flow or series flow chilling systems, senses temperature and load conditions and uses feedback in conjunction with synchronously and asynchronously timed logic circuitry to automatically control loading, unloading and sequencing of the compressor or compressors in the system in selected increments, thereby yielding a significant reduction in energy consumption as well as increased precision in maintaining a desired chill temperature. Additional circuitry provides for remote manual control as well as safety shut-off and failure indication. Alternative embodiments using solid state logic, including a microprocessor embodiment, are also disclosed.

Abstract: A two-stage refrigeration system has a gas-liquid intercooler which subcools liquid refrigerant passing from the feed tank to the evaporators. The feed tank is maintained at the desired pressure adequate for supplying the evaporators and receives return liquid from a separating system which is pressurized from the receiver. In a modification the system may be operated as a single stage or as a compound system.

Abstract: Electrical control means for use in a heat pump system having dual compressors wherein the operation of each compressor can be staged independently and automatically except for those periods when the outdoor heat exchanger is undergoing defrost wherein both compressors are placed in operation.

Abstract: There is provided a heat pump installation for the heating of tap water and for room heating purposes e.g., associated office spaces in large warehouses where a number of refrigerators are operating. The heat pump receives its input heat from the heat liberated by the refrigerators.

Abstract: A refrigeration unit for providing both heating and cooling employing two, closed circuit, mechanical vapor compression systems operatively connected by an indirect heat exchanger positioned between the discharge of the compressor and the condenser of a first cooling system, the exchanger also serving as the evaporator in the second heating system.

Abstract: A heating arrangement, in which the circulating heat transfer medium for radiators is heated by condensation of a refrigerant in a heat pump, is controlled by relays in the energizing circuits of the several, independently driven pumping units of the compressor in the heat pump in response to the difference between the temperature of the atmosphere outside the heated area and the temperature of the circulating heat transfer medium to reduce the pumping energy consumed in response to the rising temperature of the heat transfer medium, and thereby to improve the efficiency of the heating arrangement.

Abstract: An air conditioning system having latent and sensible cooling capabilities is disclosed herein. The mode of operation is determined by the temperature and humidity conditions of the enclosure.

Abstract: In a phase-change refrigeration circuit including a compressor, condenser and evaporator and connecting conduits all charged with a phase-change refrigerant, each of the compressor, condenser and evaporator having an input and output, the improvement comprising a heat exchanger including a container filled with a liquid convection fluid with the container enclosing a portion of the circuit such that the convection fluid is in heat-conducting relation to the system refrigerant flowing through the said enclosed portion. One such heat exchanger filled with convection fluid may be disposed between the compressor and the condenser of the system to enclose the conduit extending therebetween. Another such heat exchanger container filled with convection fluid may be used to enclose the evaporator of a high-stage circuit and the condenser of the low-stage circuit, the high-stage and low-stage being cascaded together.

Abstract: In an engine powered vehicle having a generator, a storage battery, and a refrigerated compartment having a refrigerated cooling coil, a compressor is connected to the cooling coil, the condensor is connected to the compressor. A refrigerant expansion means is connected to the compressor and to the cooling coil. In one embodiment a second compressor is operatively connected to the vehicle engine; in another a second condensor is connected to the second compressor, and in another the refrigeration system includes a third compressor connected in parallel with the first compressor and the second compressor. A second condensor, a second means to expand refrigerant, and a second cooling coil is connected with the third compressor to refrigerate two separate compartments. Each embodiment preferably has a control to operate the systems relative to the refrigeration demand of the system.

Abstract: Refrigerating apparatus and method including a compressor refrigerating system and an absorber refrigerating system having respective separated closed circuits in operative relationship with respect to one another such that a coolant from the compressor system is usable for cooling a refrigerant of the absorber system. The compressor and absorber system are alternatingly operated to cool a common container with refrigerant store of the absorber system being replenished during operation of the compressor system by boiling out refrigerant from an absorber composition utilizing heat from coolant compressed and heated by a compressor of the compressor system.

Abstract: The invention relates to an air conditioning system for producing refrigerated air, comprising as many evaporator convectors as there are rooms to be air-conditioned, each evaporator being connected by means of supply and return pipes, to a condensation unit placed outside the rooms that are to be air-conditioned.