Abstract: A drying fan has a shroud with a shape selected to improve fan efficiency by designated fluid dynamics of air flow through the fan.

Abstract: A cross-flow heat exchanger, method of making a cross-flow heat exchanger, and a dehumidifier are provided. The cross-flow heat exchanger has an axial flow path extending through the heat exchanger from an inlet to an outlet and a transverse flow path oriented transversely to the axial flow path and extending through the heat exchanger from an inlet to an outlet. The transverse flow path is adjacent to and separate from the axial flow path. The surface area of the inlet of the axial flow path is less than the surface area of the outlet of the axial flow path. In a preferred embodiment, the heat exchanger has an exterior shape that is trapezoidal.

Abstract: A cross-flow heat exchanger, method of making a cross-flow heat exchanger, and a dehumidifier are provided. The cross-flow heat exchanger has an axial flow path extending through the heat exchanger from an inlet to an outlet and a transverse flow path oriented transversely to the axial flow path and extending through the heat exchanger from an inlet to an outlet. The transverse flow path is adjacent to and separate from the axial flow path. The surface area of the inlet of the axial flow path is less than the surface area of the outlet of the axial flow path. In a preferred embodiment, the heat exchanger has an exterior shape that is trapezoidal.

Abstract: A drying fan has a shroud with a shape selected to improve fan efficiency by designated fluid dynamics of air flow through the fan.

Abstract: A cross-flow heat exchanger, method of making a cross-flow heat exchanger, and a dehumidifier are provided. The cross-flow heat exchanger has an axial flow path extending through the heat exchanger from an inlet to an outlet and a transverse flow path oriented transversely to the axial flow path and extending through the heat exchanger from an inlet to an outlet. The transverse flow path is adjacent to and separate from the axial flow path. The surface area of the inlet of the axial flow path is less than the surface area of the outlet of the axial flow path. In a preferred embodiment, the heat exchanger has an exterior shape that is trapezoidal.

Abstract: Efficient dehumidification is provided by directing air flow through a coil (30, 60) to cool the air below the dew point such that water vapor in the air is condensed to liquid to dehumidify the air, and then directing air flow through the coil to heat the air to a temperature below the incoming air to the coil and above the dew point of the air. Air flow is directed along a first set of coil sections (42, 64) giving up heat to refrigerant in the first set of coil sections to evaporate refrigerant in the first set of coil sections, and then directing the air flow along a second set of coil sections (44, 66) absorbing heat from refrigerant in the second set of coil sections to condense refrigerant in the second set of coil sections. The coil sections are connected to alternately evaporate and condense refrigerant in the coil differentially such that less refrigerant is condensed in condensing coil sections than is evaporated in evaporating coil sections.

Abstract: A condenser receives hot compressed refrigerant from the heat pump compressor and transfers heat to water in water heater, refrigerant flows from the condenser through a pressure reducer to an evaporator coil in which baffles define first and second air flow paths across the coil parallel to the coil gradient. In one path the temperature of air flowing across the coil is reduced while the air gives up heat to the refrigerant. The other air flow path heats air passing across the coil. A multiplicity of pressure reducers are provided in the coil to progressively drop the temperature of the refrigerant from one end of the coil to the other. A supplemental coil can be used in conjunction with the second air flow path to heat air further. The supplemental coil may receive hot refrigerant directly from the condenser.

Abstract: A combined storage tank and heat exchanger unit for heating water including a watertight tank having a water inlet in the lower portion thereof and a pair of water outlets in the upper portion thereof. The wall of the tank is in the form of a double wall jacket having a hot refrigerant inlet at the top portion thereof and a hot refrigerant outlet at the bottom portion thereof. A cylindrical heat barrier is mounted inside the tank and spaced a short distance from the inside surface of the jacket wall to thermally isolate a relatively small amount of water in the tank in direct contact with the inner surface of the jacket. A heat barrier disc is mounted in the tank and extends horizontally across the interior thereof to thermally isolate the water in the top portion of the tank from the water in the bottom portion thereof. The water outlets communicate with the interior of the tank on opposite sides of the partition to provide heated water at two distinctly different temperatures.