A compressed air drying system is provided for removing moisture from compressed air. The dryer operates in two modes in response to the demand for compressed air. In a first mode of operation, a refrigeration compressor runs continuously and the speed of a condenser fan is varied to maintain a constant cooling temperature. In a second mode of operation, the refrigeration compressor runs intermittently between on and off periods. As result, the cooling temperature fluctuates during the second mode of operation.

A cooling system includes an ingress port to receive refrigerant in a vapor form from an evaporator, an egress port to return refrigerant in a liquid form back to the evaporator, a condenser coupled to the ingress port and the egress port, and a compressor coupled to the ingress port and the condenser. When the cooling system operates in a first mode, the condenser is configured to receive and condense the refrigerant from the vapor form into the liquid form and to return the refrigerant in the liquid form to the regress port. When the cooling system operates in a second mode, the compressor is configured to compress the refrigerant in the vapor form and to supply the compressed refrigerant to the condenser to be condensed therein.

An ice maker for forming ice having a refrigeration system, a water system, and a control system. The refrigeration system includes a compressor, a condenser, an ice formation device, and a condenser fan comprising a fan blade and a condenser fan motor for driving the fan blade. The water system supplies water to the ice formation device. The control system includes a controller adapted to operate the condenser fan motor at a first speed in a forward direction when the ice maker is making ice and adapted to operate the condenser fan motor at a second speed in a reverse direction when the ice maker is not making ice. Operating the condenser fan motor at the second speed in the reverse direction is sufficient to reduce the amount of dirt, lint, grease, dust, and/or other contaminants on or in the condenser.

A method of operating a chiller system includes receiving an input from at least one sensor associated with a compressor of the chiller system, determining that the compressor is experiencing a surge or rotating stall event, adjusting at least one operating parameter associated with a heat rejection heat exchanger of the chiller system in response to determining that the compressor is experiencing the surge or rotating stall event, and reducing a condenser saturation temperature by adjusting the at least one operating parameter.

A system for controlling or optimizing the performance of a vapor compression system by modifying the actuator commands via an output interface, that realizes thermofluid property functions and their derivatives as spline functions which are represented in a coordinate system that is aligned with a fluid saturation curve. The system includes an interface configured to receive measurement data from sensors, a memory configured to store thermofluid property data and computer-executable programs including a B-spline method, and a processor for performing the computer-implemented method. The processor is configured to take as input two thermofluid property variables, and compute a coordinate transformation in which one axis of the coordinates is aligned with the liquid and vapor saturation curves. In the saturation-curve aligned coordinates, a spline function represents the thermofluid property function, with coefficients and knots stored in memory. The spline function is constructed in a manner such that derivatives of the thermofluid property function may be discontinuous across the saturation curve.

A cooling system for a vehicle is provided. The cooling system includes a condenser having a first inlet header, a first outlet header, and a plurality of first tubes connecting between the first inlet header and the first outlet header. Additionally, a radiator of the system includes a second inlet header, a second outlet header, and a plurality of second tubes connecting between the second inlet header and the second outlet header. A fan assembly is disposed in front of or behind the condenser and the radiator and includes at least one cooling fan. The condenser and the radiator are arranged side by side on the front of the vehicle.

A method of detecting electrical failure in a refrigeration system is provided. The method includes determining whether a present superheat of the refrigeration system is between a maximum superheat and a minimum superheat for the refrigeration system, the maximum superheat and the minimum superheat defining a normal operating range. The method also includes detecting an electrical property of an expansion valve assembly of the refrigeration system responsive to the superheat being outside the normal operating range. The method further includes determining whether the expansion valve assembly as experienced an electrical failure based on at least the electrical property. A signal indicating that the expansion valve has experienced an electrical failure is generated based on a determination that the expansion valve assembly has experienced the electrical failure.

A vehicle air-conditioning apparatus is provided which is capable of expanding an effective range of a dehumidifying and heating mode to achieve comfortable vehicle interior air conditioning. A control device (controller) executes a dehumidifying and heating mode to let a refrigerant discharged from a compressor 2 radiate heat in a radiator 4, let a part of the refrigerant flow from a bypass circuit (refrigerant pipe 13F) to an indoor expansion valve 8, and let the residual refrigerant flow through an outdoor expansion valve 6. In the dehumidifying and heating mode, the control device has a state of controlling the operation of the compressor 2, based on a heat absorber temperature Te and executes a radiator temperature priority mode which enlarges a capability of the compressor when heat radiation in the radiator is insufficient.

A free cooling outdoor unit includes: a refrigerant circuit through which refrigerant circulates; a brine circuit through which brine circulates; a water circuit through which water circulates; a fan configured to send air to the second heat exchanger; a flow control valve configured to control a circulation amount of the brine in the brine circuit; a water temperature detection sensor configured to detect a water temperature in the water circuit; an outside air temperature sensor; and a controller configured to control, where the outside air temperature is equal to or lower than a freezing temperature of the brine, the circulation amount of the brine based on the water temperature such that a brine temperature is prevented from reaching a temperature equal to or lower than the freezing temperature of the brine.

A system for controlling a capacity of a compressor includes a motor of the compressor including a main winding connected at a connection point to an auxiliary winding and a drive configured to control a speed of the motor. The system includes a first switch configured to selectively connect the main winding to either a first line voltage or a first output of the drive, a second switch configured to selectively connect the connection point to either a second line voltage or a second output of the drive, and a third switch configured to selectively connect the auxiliary winding to either a capacitor or a third output of the drive. The system includes a solenoid valve configured to selectively either operate in a first capacity or a second capacity. The system includes a control module configured to control the drive, the first switch, the second switch, and the third switch.