Abstract: A power distribution system for an air handler is reconfigureable by way of selectively connectable plug-in connectors. The air handler includes a blower associated with a first plug-in connector that is selectively connectable to a second plug-in connector of a heater and a third plug-in connector of an electric air cleaner. If the air handler includes a heater but not the electric air cleaner, then the blower connector plugs into the heater connector. If the air handler includes an electric air cleaner but not a heater, then the blower plugs into the connector of the air cleaner. And if the air handler includes both a heater and an electric air cleaner, then a three-way electrical connector couples the blower to both the heater and the air cleaner.

Abstract: An air-handler includes an AC induction motor that drives a blower to move air across a heat exchanger. A switch system selectively determines whether the blower motor operates at its rated full speed or at a reduced speed. For full speed operation, the switch system couples an AC supply at a nominal line frequency directly to the blower motor and bypasses an inverter. For reduced speed operation, the switch system couples a lower frequency output of the inverter to the blower motor. The blower is operated at a reduced speed during a pre-run dehumidification mode, a post-run heat recovery mode, and/or an electronic air-cleaning mode. The switch system allows the rated current capacity of the inverter to be substantially less that the rated full load current of the blower motor.

Abstract: A refrigeration chiller employs a centrifugal compressor the impellers of which are mounted on a shaft which is itself mounted for rotation using rolling element bearings lubricated only by the refrigerant which constitutes the working fluid of the chiller system. Apparatus is taught for providing liquid refrigerant to (1.) the bearings immediately upon chiller start-up, during chiller operation and during a coastdown period subsequent to shutdown of the chiller and (2.) the drive motor of the chiller's compressor for motor cooling purposes. By use of a variable speed-driven motor to drive the compressor, optimized part load chiller performance is achieved in a chiller which does not require or employ an oil-based lubrication system.

Abstract: A valve in valve assembly. The assembly comprises a housing having an internal passage, a valve body in the housing and movably operable to control process fluid flow through the passage, and a chamber in the valve body. The chamber is open to the passage at a first chamber end. A valve core in the chamber controls service fluid flow the chamber.

Abstract: A single piece tip seal for use in scroll compressors is produced using a polyetheretherkeytone base material injected into a mold having two ingates to the mold cavity.

Abstract: A method of controlling an expansion valve including the steps of: measuring a primary system condition; determining an error in the primary system condition; measuring a secondary system condition; determining an error in the secondary system condition; and modulating the expansion valve based upon the larger of the first or second error.

Abstract: A heat exchanger within a sheet metal enclosure includes mounting structure that provides double vibration isolation to minimize noise. The mounting structure includes at least one resilient vibration isolator that couples the heat exchanger to a vibration isolation plate, and includes other similar isolators that couple the plate to the enclosure. The mass of the plate is sufficient to somewhat emulate a dual mass/spring system having two degrees of freedom. To this end, the plate is preferably thicker than the sheet metal walls of the enclosure. The double vibration isolated heat exchanger is especially applicable to systems having several heat pumps that are mounted overhead. In some embodiments, the heat pump's refrigerant compressor is also resiliently mounted to the vibration isolation plate.

Abstract: An air conditioning unit. The unit comprises a housing having a first side, a second side, a return air end wall, a supply air end wall, a return air interior, a supply air interior and a heat exchange coil operably connected to the first and second sides and separating the return air and supply air interiors. The first side includes a return air aperture and a supply air aperture, and the second side includes a return air aperture and a supply air aperture. The supply air end wall includes a supply air aperture wherein the supply air and return air apertures are of identical configuration. The air conditioning unit also includes chamfered corners, and a hanger assembly and a U-shaped channel bracket located at each chamfered corner.

Abstract: A method of controlling a variable speed draft inducer motor and fan in a gas furnace. The method comprises the steps of: detecting a first fault driving the motor to a maximum operating range; detecting a second fault forcing the motor to operate towards a minimum operating range; and generating a fault signal if both faults are detected substantially simultaneously.

Abstract: A hermetic reciprocating compressor employs a motor end cap through which suction gas passes in heat exchange contact with the compressor drive motor enroute to the compressor. The end cap has a suction gas aperture and employs apparatus for preventing the entry of debris thereinto and defines a closeable aperture through which the gap between the rotor and stator of the compressor drive motor is accessible during the compressor manufacturing process.

Abstract: In a preferred embodiment, a single motor drives both oil and refrigerant pumps in a refrigeration chiller, the motor and oil pump being disposed in the chiller's oil supply tank and the refrigerant pump being disposed exterior thereof. The refrigerant pump pumps liquid refrigerant to the chiller's compressor section so as to cool the motor by which the compressor is driven while the oil pump pumps oil to chiller locations that require lubrication when the chiller is in operation. A uniquely designed impeller permits low pressure liquid refrigerant in its liquid state to be reliably pumped to a location of use, without significant flashing, from a source location which is at a height only a short distance above the pump inlet. A stand alone refrigerant pump embodiment is also described.

Abstract: In a preferred embodiment, a single motor drives both oil and refrigerant pumps in a refrigeration chiller, the motor and oil pump being disposed in the chiller's oil supply tank and the refrigerant pump being disposed exterior thereof. The refrigerant pump pumps liquid refrigerant to the chiller's compressor section so as to cool the motor by which the compressor is driven while the oil pump pumps oil to chiller locations that require lubrication when the chiller is in operation. A uniquely designed impeller permits low pressure liquid refrigerant in its liquid state to be reliably pumped to a location of use, without significant flashing, from a source location which is at a height only a short distance above the pump inlet. A stand alone refrigerant pump embodiment is also described.

Abstract: An apparatus for generating a spark, particularly for igniting the gas in a gas appliance. The apparatus includes a spark generator adjacent to a combustible gas burner. The spark generator consists of at least two spark electrodes connected to a high voltage transformer. The transformer and electrodes, preferably sealed or supported in an epoxy or ceramic shell, form one easily replaceable unit. A remote circuit is operatively associated with the high voltage transformer for igniting a spark. The transformer and electrodes are located at a distance from the spark initiating circuitry and other circuitry, which in combination with the epoxy or ceramic shell provides enhanced EMI protection for sensitive remote circuitry. The ignition system may also includes a flame sensing mechanism which detects when the burner is lit.

Abstract: A tube and shell evaporator operable at near freezing includes a temperature sensor that senses the temperature of chilled water discharging from one or just a few of the very coldest tubes, whereby the sensed temperature is less than the average leaving chiller water temperature (LCWT). The result provides an exceptionally low LCWT, which can be especially desirable in district cooling systems where the chilled water is usually piped a great distance.

Abstract: A refrigeration chiller makes use of the flow of oil from an oil sump location to the chiller's compressor to power an eductor to return oil which has made its way to the evaporator of the chiller system from the evaporator to the compressor.

Abstract: A screw compressor in a refrigeration chiller includes one or more baffles disposed in the compressor housing so as to intercept and redirect oil which may flow and/or be blown, under certain operating conditions, in an upstream direction against the stream of suction gas that flows into the compressor from the evaporator. The baffles cause oil to be retained in the compressor rather than being blown back to the system evaporator to ensure that sufficient oil is available to the compressor under all operating conditions and eliminates the need for structure/apparatus in the evaporator dedicated to returning such oil to the compressor.

Abstract: A refrigeration unit having a compressor that includes a cast member, a cavity formed in the cast member, and an oil filter element dividing the cavity into an inlet cavity and an outlet cavity. An inlet port for directing the unfiltered oil into the inlet cavity and an outlet port for directing filtered oil out of the outlet cavity are also included. The filter element is secured in the cavity between an integral plate on one end and ears on the opposite end. A seal between the cast member and the removable cover is included. Also included is another seal positioned between the inlet and outlet cavities. The filter element may be cylindrical. At least one isolation valve that prevents or allows flow into and out of the filter cavity may be included. The inlet port may be formed in the cast member and the outlet port may be formed in the removable cover, or vice versa. At least one lubrication point and an oil conduit communicating between the lubrication port and the outlet port are included.

Abstract: A bi-directional refrigerant metering and expansion valve. The bi-directional valve comprises a body; a short tube portion in the body, a heating inlet portion and a cooling inlet portion. The short tube portion includes a tubular portion having a short tube length, a short tube diameter, and a pre-selected short tube length to short tube diameter ratio and includes first and second ends interconnected by the tubular portion. The heating inlet portion is connected to the first end of the short tube portion, and includes a heating inlet chamfer having a first length and a first angle of a first magnitude. The cooling inlet portion is connected to the second end of the short tube portion, and includes a cooling inlet chamfer having a second length and a cooling inlet angle of a second magnitude. The second length is greater than the first length.

Abstract: An air conditioning unit comprising: a housing having a first half and a second half; the first half of the housing containing an indoor heat exchange coil and a blower moving air through said coil from at least a housing inlet to a housing outlet. The blower discharges into a diffuser duct having a diffuser section with a first segment and a second segment where the first and second segments have first and second respective and differing angles of diffusion.

Abstract: A refrigeration chiller employs a centrifugal compressor the impellers of which are mounted on a shaft which is itself mounted for rotation using rolling element bearings lubricated only by the refrigerant which constitutes the working fluid of the chiller system. Apparatus is taught for providing liquid refrigerant to (1.) the bearings immediately upon chiller start-up, during chiller operation and during a coastdown period subsequent to shutdown of the chiller and (2.) the drive motor of the chiller's compressor for motor cooling purposes. By use of a variable speed-driven motor to drive the compressor, optimized part load chiller performance is achieved in a chiller which does not require or employ an oil-based lubrication system.