Abstract: An absorption chiller includes a vertically split absorber section the upper portion of which is a high temperature absorber and the lower portion of which is a low temperature absorber. Weak solution is pumped in parallel from the absorber to both a low temperature generator and a high temperature generator. The low temperature generator is disposed vertically above the high temperature generator. Concentrated solution flows, in parallel, from the low temperature generator to the low temperature absorber and from the high temperature generator to the high temperature absorber.

Abstract: A device and system for, and a method of attracting waterfowl. The method comprises the steps of: providing a lighter than air object; attaching a deployable retainer to the lighter than air object; releasing the lighter than air object proximal a waterfowl landing area; allowing the lighter than air object to deploy to an area downwind of the waterfowl landing area; and retrieving the lighter than air object from the downwind area to the waterfowl landing area.

Abstract: Oil return from the evaporator to the compressor of a refrigeration chiller is accomplished by routing the suction piping that communicates between the chiller's evaporator and compressor to a location physically below the lubricant-rich pool at the bottom of the evaporator shell and by connecting the lubricant-rich pool to the compressor suction piping at a location where the suction piping is disposed physically below the pool.

Abstract: Oil return from the evaporator to the compressor of refrigeration chiller is accomplished by routing the suction piping that communicates between the chiller's evaporator and compressor to a location physically below the lubricant-rich pool at the bottom of the evaporator shell and by connecting the lubricant-rich pool to the compressor suction piping at a location where the suction piping is disposed physically below the pool.

Abstract: An HVAC (heating, ventilating, and air conditioning) control and method for interpreting a broad range of input voltages generates a series of voltage pulses whose quantity increases with the amplitude of the input voltages. Upon counting the pulses or accumulating them across a capacitor, the control applies an algorithm to determine whether an input voltage should be interpreted as a logic-1 or a logic-0. The control can accept AC input voltages having nominal amplitudes of either 110 or 220-volts. In some embodiments, software-based hysteresis helps filter out electrical noise and distinguish input signals that are marginally between a logic-1 and a logic-0.

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 refrigerant system selectively operable in a cooling mode, a reheat cooling mode, and a heating mode, includes a primary heat exchanger and a reheat heat exchanger that condition air for a room. In the cooling mode, the primary heat exchanger functions as an evaporator that cools the air, while the reheat heat exchanger is inactive. In the reheat cooling mode, the primary heat exchanger cools the air, and hot refrigerant in the reheat heat exchanger reheats the air to provide dehumidified air at or near room temperature. In the heating mode, the primary heat exchanger functions as a condenser that heats the air, while the reheat heat exchanger is inactive. When the reheat heat exchanger is inactive, a unique venting arrangement prevents the inactive heat exchanger from becoming flooded with liquid refrigerant.

Abstract: A generator for an absorption chiller boils an absorption solution with steam heat by conveying the steam through a tube bundle with the steam flowing counter to the flow of solution. The tube bundle runs downhill in the direction of steam flow, while in some embodiments of the invention a bottom surface of the generator runs uphill in the direction of solution flow. The amount of solution in the generator is kept to an appropriately low level by submerging the tube bundle deeper at one end of the generator than the other.

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 self-contained air conditioner cools a building's air using a water-cooled economizer coil and two refrigerant evaporators. The two evaporators are provided by two separate refrigeration circuits, each having its own water-cooled condenser. A water circuit interconnecting the economizer and the two condensers is reconfigureable to selectively operate the air conditioner in a normal mode or, if conditions permit, in an energy-saving economizer mode. In the normal mode, the water circuit conveys cooling water in series through both condensers while bypassing the economizer coil. In the economizer mode, the water flows in series through the economizer and one of the condensers while bypassing the other. The refrigerant circuit whose condenser is bypassed can thus be deactivated to save energy. The economizer coil and the condenser it bypasses have generally the same flow resistance to water flow.

Abstract: A falling film evaporator for use in a vapor compression refrigeration chiller preferably employs a two-phase refrigerant distributor that overlies the tube bundle in the evaporator shell. The tube bundle defines at least one vapor lane which facilitates the conduct of refrigerant vapor from the interior of the tube bundle to the exterior thereof in a manner which does not substantially affect the vertically downward flow of liquid refrigerant through the tube bundle and across the vapor lane.

Abstract: A impeller shaft assembly is disclosed for use in a refrigerant compressor, and more particularly in a commercial high-speed centrifugal impeller shaft configuration. The impeller shaft assembly includes a contoured spacer body. The contoured spacer body includes a front face, a rear face, a recessed spring bearing surface in its rear face, and a spring spacing abutment including a shoulder that is seated against a protective washer. The contoured spacer body functions to prevent the headed front end of a fastener from coming into direct contact with a spring assembly and protective washer. Consequently, the spring assembly and protective washer are not sized to correspond to the cross-section area of the headed front end as disclosed in the prior art. Instead, the protective washer and spring assembly are sized to fit the rear face of the contoured spacer body, which in turn is sized to fit the front face of a first stage impeller.

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 method of controlling chiller capacity in a chiller system. The method comprises the steps of: measuring entering the fluid temperature of a fluid entering a heat exchanger; measuring the fluid temperature of the fluid leaving the heat exchanger; determining a desired leaving fluid temperature; establishing chiller capacity as a function of the difference between leaving fluid temperature and the desired leaving fluid temperature; and adjusting the determined chiller capacity as a function of the difference between entering fluid temperature and the desired leaving fluid temperature.

Abstract: An expansion device in a refrigeration chiller defines at least two fixed orifices and employs at least two positionable valve members in order to minimize the overall flow area through the expansion device under a first set of chiller operating conditions, to maximize the overall flow area through the expansion device under a second set of chiller operating conditions and to define a flow area intermediate said minimum and said maximum flow areas when a third set of chiller operating conditions exist.

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 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.