Abstract: A system (170; 300; 400) comprising a compressor (22). A heat rejection heat exchanger (30; 420) is coupled to the compressor to receive refrigerant compressed by the compressor. A separator (180) has: a vessel (181); an inlet (50) coupled to the heat rejection heat exchanger to receive refrigerant; a first outlet (54) in communication with a headspace of the vessel; and a second outlet (52, 52?) in communication with a lower portion of the vessel. The system has a heat exchanger (182; 220; 220?; 220?; 220??) for transferring heat from refrigerant passing from a heat rejection heat exchanger to liquid refrigerant in the separator.

Abstract: A seal member (80) for a rotary regenerative scrubber (10) includes a hub (30), a rim (48) circumferentially surrounding the hub, and a plurality of spokes (86) extending from the hub to the rim. The hub, rim, and spokes define an axially facing seal face (88) configured to form a sealing engagement with an opposed seal surface of a rotary regenerative scrubber, and a mounting face (90) axially opposed to the seal face configured for mounting to a rotor assembly (20) of a rotary regenerative scrubber. The seal face includes a labyrinth seal (92) defined therein.

Abstract: A refrigerant system capable of operating at multiple capacity modes includes an evaporator, a multi-stage compressor assembly, a first fluid flow path, a second fluid flow path, a first valve, and a second valve. The multi-stage compressor assembly has a first stage and a second stage. The first fluid flow path extends from the evaporator to the first stage of the multi-stage compressor assembly. The second fluid flow path connects to the first fluid flow path and to the multi-stage compressor assembly between the first stage and the second stage.

Abstract: An ejector has: a motive flow inlet (40); a secondary flow inlet (42); an outlet (44); a motive flow nozzle (242) having an outlet (110); a primary flowpath from the motive flow inlet through the motive flow nozzle to the ejector outlet; a secondary flowpath from the secondary flow inlet to the ejector outlet, merging with the primary flowpath at the motive nozzle outlet; a control needle (200; 300; 400) shiftable along a range of motion between a first condition and a second condition and seated against the motive nozzle in the second condition. The needle comprises: a main shaft (210); a tip (204); a first portion (220; 320) converging toward the tip; and a shoulder portion (214; 314; 422) between the first portion and the main shaft and seated against the motive nozzle in the second condition and converging toward the tip at a greater angle (?1; ?1 2) than an angle (?2; ?2 2) of the first portion.

Abstract: A suction modulation valve is throttled when conditions in a refrigerant system indicate that an undesirable amount of liquid refrigerant might otherwise be delivered to the compressor. As an example, the throttling would occur at start-up, among other conditions. Throttling the suction modulation valve reduces the amount of refrigerant reaching the compressor and thus ensures that any liquid refrigerant would be likely “boiled off” before raising any problems in the compressor. Other control steps can also be performed to alleviate flooded compressor operation with liquid refrigerant. Such steps, for example, can include actuating heaters, discharge valve throttling, by-passing refrigerant from an intermediate compression point back to suction, controlling the speed of the condenser fan can be performed independently or in combination including the suction modulation valve throttling.

Abstract: An ejector has: a motive flow inlet (40); a secondary flow inlet (42); an outlet (44); a motive nozzle (204); a diffuser (118); and a control needle (132) shiftable between a first position and a second position. The ejector comprises: an inlet body (210; 400) bearing the motive flow inlet and the secondary flow inlet; a diffuser body (212) forming the diffuser and bearing the outlet; a motive nozzle insert (204) forming the motive nozzle in a compartment (240) in the inlet body; and a needle guide insert (270) in the motive nozzle insert.

Abstract: A refrigerant system control software upgrades are remotely downloaded over information carrying media. The software upgrades can be timed to occur when the Internet traffic is low. Once the upgrade has been received, a verification test may be performed for the refrigerant system components affected by the software upgrade. The test is monitored, and the results are sent back to the remote location such that the remote location can ensure the software upgrade was successful.

Abstract: There is provided a space heating system (100) that includes a heat pump (105), a supplemental gas heating system (110), and a controller (115) connected to the heating system (100). The controller (115) controls a switching set point, which in its simplest case is an ambient temperature at which the controller (115) switches between operation of the heat pump (105) and operation of the supplemental gas heating system (110). The controller (115) is connected to a real time source of information (195) providing at least one of current electricity prices and current prices of a source of heating such as gas, and changes the switching set point in response to changes in at least one of the electricity prices and the gas prices. There is also provided a method for control of the heating system (100).

Abstract: A backer for a reed valve has: a first surface for engaging the valve reed; a second surface opposite the first surface; a base portion for mounting to a compressor housing; a distal portion for engaging a distal portion of the reed; and at least one trunk connecting the base portion to the distal portion. The first surface is transversely convex along a portion of the trunk. The trunk is relatively wider near the base portion than near the distal portion.

Abstract: A refrigerant system is provided with a pulse width modulation suction valve and a second valve on a line that bypasses the pulse width modulation suction valve. This second valve has a variable opening. In this manner, the pressure within the compressor shell is maintained at the lowest possible level regardless of the system operating conditions, when the pulse width modulation suction valve is cycled to a closed position. Further, the second valve can continue providing capacity control, should the pulse width modulation suction valve fail.

Abstract: A refrigerant system control operates tandem compressors. If one of the monitored system conditions does not change as each of the tandem compressors or associated components is brought on line, then a determination is made that the respective component is malfunctioning. A refrigerant system can also be additionally equipped with other functions and components, such as variable speed drive, economizer circuit, unloader bypass, and reheat circuit. In case of a reheat circuit, the system can have single or multiple compressors. The control algorithm can also be updated such that that particular malfunctioning component is eliminated from the operational sequence.

Abstract: A system has a compressor. A heat rejection heat exchanger is coupled to the compressor to receive refrigerant compressed by the compressor. An ejector has a primary inlet coupled with heat rejection heat exchanger to receive refrigerant, a secondary inlet, and an outlet. The system has a heat absorption heat exchanger. The system includes means for providing at least of a 1-10% quality refrigerant to the heat absorption heat exchanger and an 85-99% quality refrigerant to at least one of the compressor and, if present, a suction line heat exchanger.

Abstract: A multi-rotor screw compressor includes a housing, a sun rotor, and first and second planet rotors. The first planet rotor intermeshes with the sun rotor to define a first compression pair. The second planet rotor intermeshes with the sun rotor to define a second compression pair. The first and second compression pairs are rotatably mounted in the housing. The housing includes a first port, a portion of which is in communication with the first compression pair, and a second port, a portion of which is in communication with the second compression pair. The portions of the first and second ports which communicate with the first and second compression pairs have a different geometry for offsetting pulsations in a working fluid flowing through the ports.

Abstract: A refrigerant system operates in an environment defined by three distinct temperature levels, such as, for instance, the outdoor ambient temperature level, the indoor temperature level and the refrigeration temperature level. The refrigerant system is provided with an air-to-refrigerant heat exchanger located within the general indoor environment and connected to receive the flow of refrigerant from a heat rejection heat exchanger. The air-to-refrigerant heat exchanger gives off heat to the indoor air and in the process further cools the refrigerant flowing to an expansion device to thereby increase the cooling effect provided by an evaporator to the refrigeration area. Provisions are also made to partially or entirely bypass the air-to-refrigerant heat exchanger and/or the heat rejection heat exchanger, on a selective basis.

Abstract: A pulse width modulation control is provided for a suction valve on a suction line, delivering refrigerant into a housing shell of a compressor. When the suction valve is closed, the pressure within the housing shell can become very low. Thus, a pressure regulator valve is included within the refrigerant system to selectively deliver a limited amount of refrigerant into the housing shell when the suction valve is closed. The delivery of this limited amount of refrigerant ensures that a specified pressure is maintained within the housing shell to achieve the most efficient operation while at the same time preventing problems associated with damage to electrical terminals, motor overheating and excessive discharge temperature.

Abstract: A reciprocating piston compressor for use in a refrigerant compression circuit comprises first and second intake manifolds, first and second reciprocating piston compression units, an outlet manifold and a first pulsing valve. The intake manifolds segregate inlet flow into the compressor. The first and second reciprocating piston compression units receive flow from the first and second intake manifolds, respectively. The outlet manifold collects and distributes compressed refrigerant from the compression units. The first pulsing valve is mounted externally of the first intake manifold to regulate refrigerant flow into the first intake manifold. In another embodiment, a second valve is mounted externally of the second intake manifold to regulate flow into the second intake manifold, and the first and second valves are operated by a controller. The controller activates the first valve with variable width pulses having intervals less than an operating inertia of the refrigerant compression circuit.

Abstract: A refrigerant system can be operated in either vapor injection mode or unloaded mode. A restriction to the vapor injection flow is incorporated into the refrigerant system. The restriction is placed on the vapor injection line upstream of a point where the injection line meets the unloader line. In this case, the flow is restricted for the vapor injection mode of operation to a desired level. However, when the refrigerant system operates in the unloaded mode, there is no restriction to the by-pass flow, which is beneficial to the system performance in this mode of operation. In one of the embodiments, the restriction area can be adjusted to achieve the best performance during the vapor injection mode of operation in relation to the operating conditions.

Abstract: A refrigerant system utilizes an expander to expand refrigerant and to drive or assist in driving an associated compressor. By varying the compressor load, the speed of the expander can be adjusted to achieve the desired thermodynamic characteristics of the expanding refrigerant and enhance expander operation.

Abstract: A heating system includes a refrigerant boiler including a heat source for heating a refrigerant from a liquid state to a vapor state, a boiler outlet and a boiler inlet; a heat exchanger in fluid communication with the refrigerant boiler, the heat exchanger including a upper manifold having a heat exchanger inlet coupled to the boiler outlet, a lower manifold having a heat exchanger outlet coupled to the boiler inlet and a plurality of tubes connecting the upper manifold and the lower manifold, wherein refrigerant passes from the upper manifold to the lower manifold via gravity; and a fan moving air over the heat exchanger to define supply air for a space to be heated.

Abstract: A refrigerant vapor compression system includes a compression device, a heat rejecting heat exchanger, an economizer heat exchanger, an expander and an evaporator disposed in a refrigerant circuit. An evaporator bypass line is provided for passing a portion of the refrigerant flow from the main refrigerant circuit after having traversed a first pass of the economizer heat exchanger through the expander to partially expand it to an intermediate pressure and thence through a second pass of the economizer heat exchanger and into an intermediate pressure stage of the compression device. An economizer bypass line is also provided for passing a portion of the refrigerant from the main refrigerant circuit after having traversed the heat rejecting heat exchanger through a restrictor type expansion device and thence into the evaporator bypass line as liquid refrigerant or a mix of liquid and vapor refrigerant for injection into an intermediate pressure stage of the compression device.