Abstract: A non-intrusive refrigerant charge level indicator includes a structure for measuring at least one temperature at an outside surface of a two-phase refrigerant line section. The measured temperature can be used to determine the refrigerant charge status of an HVAC system, and can be converted to a pressure of the refrigerant in the line section and compared to a recommended pressure range to determine whether the system is under-charged, properly charged or over-charged. A non-intrusive method for assessing the refrigerant charge level in a system containing a refrigerant fluid includes the step of measuring a temperature at least one outside surface of a two-phase region of a refrigerant containing refrigerant line, wherein the temperature measured can be converted to a refrigerant pressure within the line section.

Abstract: A non-intrusive refrigerant charge level indicator includes a structure for measuring at least one temperature at an outside surface of a two-phase refrigerant line section. The measured temperature can be used to determine the refrigerant charge status of an HVAC system, and can be converted to a pressure of the refrigerant in the line section and compared to a recommended pressure range to determine whether the system is undercharged, properly charged or over-charged. A non-intrusive method for assessing the refrigerant charge level in a system containing a refrigerant fluid includes the step of measuring a temperature at least one outside surface of a two-phase region of a refrigerant containing refrigerant line, wherein the temperature measured can be converted to a refrigerant pressure within the line section.

Abstract: A heat pump system having an operable relationship for transferring heat between an exterior atmosphere and an interior atmosphere via a fluid refrigerant and further having a compressor, an interior heat exchanger, an exterior heat exchanger, a heat pump reversing valve, an accumulator, a thermal expansion valve having a remote sensing bulb disposed in heat transferable contact with the refrigerant piping section between said accumulator and said reversing valve, an outdoor temperature sensor, and a first means for heating said remote sensing bulb in response to said outdoor temperature sensor thereby opening said thermal expansion valve to raise suction pressure in order to mitigate defrosting of said exterior heat exchanger wherein said heat pump continues to operate in a heating mode.

Abstract: An improved non-stratified heat pump water heater wherein the condenser assembly of the heat pump has at least one non-vertical section and is inserted into the water tank through an existing opening in the top of the tank. The condenser assembly has either a tube-in-a-tube style or U-tube style elongated heat exchanger construction. As the refrigerant condenses along the interior surface of the condenser assembly, the heat from the refrigerant is transferred to the water. Two embodiments of the invention include a water heater having a separate sacrificial anode rod and a water heater wherein the condenser assembly acts not only as a heat exchanger but also as the sacrificial anode in the water tank by being constructed of a metal which is more likely to corrode than the metal of the tank.

Abstract: An apparatus and method for warm-liquid defrosting of the evaporator of a refrigeration system. The apparatus includes a first refrigerant expansion device that selectively expands refrigerant for cooling the evaporator, a second refrigerant expansion device that selectively expands the refrigerant after the refrigerant has passed through the evaporator, and a defrosting control for the first refrigerant expansion device and second refrigerant expansion device to selectively defrost the evaporator by causing warm refrigerant to flow through the evaporator.

Abstract: An improved heat pump water heater wherein the condenser assembly of the heat pump is inserted into the water tank through an existing opening in the top of the tank, the assembly comprising a tube-in-a-tube construction with an elongated cylindrical outer body heat exchanger having a closed bottom with the superheated refrigerant that exits the compressor of the heat pump entering the top of the outer body. As the refrigerant condenses along the interior surface of the outer body, the heat from the refrigerant is transferred to the water through the outer body. The refrigerant then enters the bottom of an inner body coaxially disposed within the outer body and exits the top of the inner body into the refrigerant conduit leading into the expansion device of the heat pump. The outer body, in a second embodiment of the invention, acts not only as a heat exchanger but also as the sacrificial anode in the water tank by being constructed of a metal which is more likely to corrode than the metal of the tank.

Abstract: A heat pump system includes, in an operable relationship for transferring heat between an exterior atmosphere and an interior atmosphere via a fluid refrigerant: a compressor; an interior heat exchanger; an exterior heat exchanger; an accumulator; and means for heating the accumulator in order to defrost the exterior heat exchanger.

Abstract: A refrigeration system having a vapor compression cycle utilizing a liquid over-feeding operation with an integrated accumulator-expander-heat exchanger. Hot, high-pressure liquid refrigerant from the condenser passes through one or more lengths of capillary tubing substantially immersed in a pool liquid refrigerant in the accumulator-expander-heat exchanger for simultaneously sub-cooling and expanding the liquid refrigerant while vaporizing liquid refrigerant from the pool for the return thereof to the compressor as saturated vapor. The sub-cooling of the expanded liquid provides for the flow of liquid refrigerant into the evaporator for liquid over-feeding the evaporator and thereby increasing the efficiency of the evaporation cycle.

Abstract: A refrigeration air conditioning system utilizing a liquid over-feeding operation is described. A liquid refrigerant accumulator-heat exchanger is placed in the system to provide a heat exchange relationship between hot liquid refrigerant discharged from condenser and a relatively cool mixture of liquid and vaporous refrigerant discharged from the evaporator. This heat exchange relationship substantially sub-cools the hot liquid refrigerant which undergoes little or no evaporation across the expansion device and provides a liquid over-feeding operation through the evaporator for effectively using 100 percent of evaporator for cooling purposes and for providing the aforementioned mixture of liquid and vaporous refrigerant.

Abstract: An adsorption-type refrigerant recovery apparatus for a refrigeration and air conditioning system that has a connection unit, a refrigerant flow direction control device, a refrigerant adsorbing/desorbing device, a refrigerant/lubricant separating device, a condensation heat exchanging device, a drying/purging device, and a refrigerant reservoir. When the refrigerant enters the connection unit from the refrigeration and air conditioning system, the flow direction control device controls the refrigerant flowing through the adsorbing/desorbing device so that the refrigerant absorbs part of the heat energy of the adsorbent and is thus vaporized. The vaporized refrigerant then enters the refrigerant/lubricant separating device to separate the lubricant therein. The flow direction control device further controls the refrigerant entering the adsorbent container to allow the adsorbent to adsorb the refrigerant. When the adsorbent is saturated, the adsorbent is heated to desorb the refrigerant in a gaseous state.

Abstract: An energy efficient absorption refrigeration system is described that is mounted on a highway vehicle, such as a truck, and that is driven by the hot exhaust gases discharged from the engine. Eutectic plates are used as the evaporator section of the refrigeration system. A novel generator-analyzer is mounted between the engine and the muffler of the truck. An efficient absorbent recirculation loop improves the efficiency of this system. Control problems are minimized by incorporating eutectic plate storage systems with the efficient absorbent recirculation loop and compact generator-analyzer. The system is designed for a variety of refrigerant-absorbent combinations.

Abstract: A vehicle eutectic plate refrigeration system provides simultaneous defrosting of part of the plate exterior surface, all of the secondary heat transfer surface and freezing of the eutectic solution within the plate. This system thus preserves sufficient space for air passage, which otherwise would be blocked by frost and ice. The system utilizes the normally rejected heat to perform a defrosting function and utilizes the ice and frost to perform the refrigerant condensing function. Hot gas from the compressor is diverted through the defrost coil where the refrigerant is for the most part condensed before it is passed through the condenser. The liquid refrigerant from the condenser is then used to freeze the eutectic solution within the plate.

Abstract: A vehicle eutectic plate refrigeration system provides simultaneous defrosting of part of the plate exterior surface, all of the secondary heat transfer surface and freezing of the eutectic solution within the plate. This system thus preserves sufficient space for air passage, which otherwise would be blocked by frost and ice. The system utilizes the normally rejected heat to perform a defrosting function and utilizes the ice and frost to perform the refrigerant condensing function. Hot gas from the compressor is diverted through the defrost coil where the refrigerant is for the most part condensed before it is passed through the condenser. The liquid refrigerant from the condenser is then used to freeze the eutectic solution within the plate.