Abstract: An HVAC system and method for configuring a controller to control a compressor including a detection system provided to determine a type of compressor. The detection system includes a processor; and a load sensing circuit connected between the processor and a controller. The controller has a plurality of output connections connectable to a compressor. The load sensing circuit senses whether a load is present on each output connection of the plurality of output connections and provides a load signal to the processor indicating whether a load is present on each output connection. The load signals are processed with the processor to determine the type of compressor is present. The controller is configured to control the compressor in response to the determined type of compressor.

Abstract: An evaporator including a shell having a first end and a second end. A plurality of tubes are disposed within the shell to circulate refrigerant through the shell. A plurality of shell inlets are in fluid communication with the shell to deliver a fluid to exchange heat in the plurality of tubes, preferably through a baffle arrangement. At least one of the shell inlets may be arranged to deliver fluid to the shell adjacent to the first end. In addition, at least one of the other shell inlets may be arranged to deliver fluid adjacent to the second end. A shell outlet is in fluid communication with the shell to discharge fluid from the shell. The shell outlet is arranged to receive the combined liquid delivered to the shell by the plurality of shell inlets.

Abstract: A discharge muffler (20) in an HVAC&R system (100) includes a plurality of tubes (34, 38, 42) of predetermined length that are disposed at a predetermined spacing in substantially mutual axial alignment by a plate (30). The tubes (34, 38, 42) are secured adjacent to a compressor discharge (24) to minimize pressure reduction, improve flow characteristics and improve efficiency of the HVAC&R system (100).

Abstract: An HVAC system and method for configuring a controller to control a compressor including a detection system provided to determine a type of compressor. The detection system includes a processor; and a load sensing circuit connected between the processor and a controller. The controller has a plurality of output connections connectable to a compressor. The load sensing circuit senses whether a load is present on each output connection of the plurality of output connections and provides a load signal to the processor indicating whether a load is present on each output connection. The load signals are processed with the processor to determine the type of compressor is present. The controller is configured to control the compressor in response to the determined type of compressor.

Abstract: A method and system for controlling refrigerant pressure in an HVAC system. The method includes providing a compressor, a condenser and an evaporator connected in a closed refrigerant loop. The condenser has a header arrangement capable of distributing refrigerant to a plurality of refrigerant circuits within the condenser. The header arrangement also is capable of selectively isolating at least one of the circuits from refrigerant flow. Refrigerant pressure is sensed at a predetermined location in the refrigeration system. At least one of the circuits is isolated when the refrigerant pressure is less than or equal to a predetermined pressure.

Abstract: A variable speed drive with a converter that is controllable to precharge a DC link is provided. The variable speed drive also includes an inverter. The converter converts a fixed line frequency, fixed line voltage AC power from an AC power source into DC power. The DC link filters the DC power from the converter. Finally, the inverter is connected in parallel with the DC link and converts the DC power from the DC link into a variable frequency, variable voltage AC power. The converter includes a plurality of pairs of power switches, wherein each pair of power switches includes a reverse blocking power switch connected in anti-parallel to another reverse blocking power switch. Alternatively, each pair of power switches includes a reverse blocking power switch connected in anti-parallel with a silicon carbide controlled rectifier.

Abstract: A compressor muffler includes a housing having an inlet end and an outlet end. A baffle arrangement extends from an interior surface of the housing. The baffle arrangement includes a surface capable of reflecting compressed fluid to attenuate noise. A valve assembly is disposed inside the baffle arrangement. The valve assembly is positionable between a first position and a second position. The valve assembly also includes a valve surface that at least partially prevents flow of fluid through the housing from the outlet end when the valve assembly is in the first position.

Abstract: A method and system is provided for gathering, processing, displaying, and manipulating data from building equipment using a dedicated HTML-driven, non-PLC controller having an integral web server. Authorized users who use microprocessor controlled devices to access the website are provided with displayed equipment data that can be selected, monitored, and adjusted based on a user profile controlled by software of the controller.

Abstract: A motor mount constructed from a single piece of sheet metal. The motor mount contains a band portion and at least three leg portions. The band portion clamps around a motor and the leg portions radiate from the band portion. The leg portions secure the motor to a housing.

Abstract: A humidity control method is provided for a multi-stage cooling system having two or more refrigerant circuits that balances humidity control and cooling demand. Each refrigerant circuit includes a compressor, a condenser and an evaporator. A hot gas reheat circuit having a hot gas reheat coil is connected to one of the refrigerant circuits and is placed in fluid communication with the output airflow from the evaporator of that refrigerant circuit to provide additional dehumidification to the air when humidity control is requested. The hot gas reheat circuit bypasses the condenser of the refrigerant circuit during humidity control. Humidity control is only performed during cooling operations and ventilation operations.

Abstract: A high efficiency, low-noise fan ring for use with a heat exchanger having an annular fan ring body attached to a coaxial mounting ring. The fan ring body extends in a substantially perpendicular direction from an inner periphery of the mounting ring. The annular body has a circumferential periphery profile defined by a plane coincident the center axis and an inner surface of the fan ring body. The periphery profile includes a transition portion and a curved portion. The transition portion extends in a substantially perpendicular direction from the mounting ring and attaches to an end of the curved portion. In order to reduce noise and increase uniformity of airflow, the length of the curved portion of the periphery profile is sufficient long to reduce recirculation of air entering the fan ring body.

Abstract: A method and system is provided for gathering, processing, displaying, and manipulating data from building equipment using a dedicated HTML-driven, non-PLC controller having an integral web server. Authorized users who use microprocessor controlled devices to access the website are provided with displayed equipment data that can be selected, monitored, and adjusted based on a user profile controlled by software of the controller.

Abstract: A chiller system includes a switched reluctance motor for powering the compressor of the chiller system. A variable speed drive with a boost converter provides a boosted voltage to the switched reluctance motor. The switched reluctance motor and the compressor may be disposed within the same hermetic enclosure and driven by a common drive shaft. Cooling for both the variable speed drive and the switched reluctance motor is provided from condenser water in the condenser water circuit, or from an intermediate liquid cooled by water from the condenser circuit to increase system efficiency. Windage losses are reduced by barriers introduced within the motor, and by maintaining a reduced pressure in the switched reluctance motor.

Abstract: A humidity control method is provided for a multi-stage cooling system having two or more refrigerant circuits that balances humidity control and cooling demand. Each refrigerant circuit includes a compressor, a condenser and an evaporator. A hot gas reheat circuit having a hot gas reheat coil is connected to one of the refrigerant circuits and is placed in fluid communication with the output airflow from the evaporator of that refrigerant circuit to provide additional dehumidification to the air when humidity control is requested. The hot gas reheat circuit bypasses the condenser of the refrigerant circuit during humidity control. Humidity control is only performed during cooling operations and ventilation operations.

Abstract: A system and process for loading control software into the control panel of a liquid chiller system is provided. A PCMCIA card socket is installed on a circuit board of a liquid chiller control system and is in direct connection with microprocessor data and address buses. A linear flash PCMCIA card having new control software for the control panel is inserted into the PCMCIA card socket when the control panel is de-energized. The control software from the PCMCIA card is loaded into a flash memory of the control system by software executed directly from the PCMCIA card. The software in the PCMCIA card erases the flash memory of the control system, copies the control software from the PCMCIA card to the flash memory and then confirms that the copy of the control software was successful. After the control software has been copied, the control panel is de-energized, the PCMCIA card is removed and the chiller system is restarted and executes the new control software stored in the flash memory.

Abstract: A variable speed drive is provided having a converter to convert an AC voltage to a DC voltage, a DC link to filter and store energy from the converter, and a plurality of inverters. Each inverter is configured to convert a DC voltage to an AC voltage and is electrically connected in parallel to the DC link. An interleaved pulse width modulation control technique is used to control the operation of the plurality of inverters and possibly the converter to lower the RMS ripple current in the DC link.

Abstract: A method for repairing an HVAC system is disclosed. The method includes monitoring a plurality of sensors positioned throughout the HVAC system and receiving data associated therewith, determining whether the data received from the plurality of sensors is within corresponding predetermined operational parameters, analyzing data determined to be outside the corresponding predetermined operational parameters to diagnose a malfunction of the HVAC system, accessing an on-board bill of materials to determine a proper replacement part to correct the malfunction, automatically ordering the replacement part, and automatically dispatching a service technician to install the replacement part.

Abstract: A control system and method for interactive startup and shutdown of a steam turbine driven chiller unit is provided. The chiller unit includes an integrated central control panel to control operation of both the steam turbine system and the refrigerant system. The central control panel has startup control system to assist an operator manually start the steam turbine system and the refrigerant system and a shutdown control system to assist an operator manually shutdown the steam system and the refrigerant system. Both the startup control system and the shutdown control system include logic for performing necessary protective actions and for notifying an operator when to perform required actions.

Abstract: A control system and method are provided for the automatic startup and shutdown of a steam turbine driven chiller unit. The chiller unit includes an integrated central control panel to control operation of both the steam turbine system and the refrigerant system. The central control panel has a startup control system to automatically start the steam turbine driven chiller unit while performing necessary protective actions and a shutdown control system to automatically stop the steam turbine driven chiller unit while performing necessary protective actions.

Abstract: A system is provided for attenuating tonal acoustic noise associated with a single positive displacement compressor, or multiple positive displacement compressors proximately located from each other. A controller selectably controls the rotational speed and the frequency of operation of each of the compressors. The controller controls the rotational speed of the compressors about a predetermined rotational speed, in a random manner, within the pre-selected speed band to reduce the magnitude of the central tonal acoustic frequency of the pressure pulsations and disperse the sound power over a wider acoustic bandwidth.