A heating, ventilation, and air conditioning system may include a refrigerant loop to circulate refrigerant, a first valve, a second valve, a sensor to measure parameters of the refrigerant, a refrigerant tank fluidly coupled to the refrigerant loop via the valves, and control circuitry communicatively coupled to the sensor, the first valve, and the second valve. The control circuitry may determine environmental conditions and detect whether an undercharge or overcharge condition is present in the refrigerant loop based at least in part on the environmental conditions and the measured parameters. The control circuitry may also instruct the first valve to open when the undercharge condition is detected to facilitate flowing refrigerant from the refrigerant tank into the refrigerant loop and instruct the second valve to open when the overcharge condition is detected to facilitate flowing refrigerant from the refrigerant loop into the refrigerant tank.

An automated refrigerant recharging system determines whether a cooling load parameter of a direct expansion (DX) cooling system that cools information technology (IT) modules of an information handling system (IHS) has reached a defined recharging threshold that results in a response of the pressure value for measurement by the pressure transducer. In response to the cooling load parameter being equal to or greater than the defined recharging threshold, a controller determines whether a pressure value of the refrigerant of the DX cooling system is less than a defined target pressure value corresponding to the defined recharging threshold. In response to determining that the pressure value of the refrigerant of the DX cooling system is less than the defined target pressure value, the controller autonomously opens a control valve to transfer refrigerant to the DX cooling system.

A refrigeration cycle apparatus includes a refrigerant circuit and a controller for controlling the refrigerant circuit. The refrigerant circuit includes a compressor, a condenser, a pressure-reducing device and an evaporator. Refrigerant circulating through the refrigerant circuit contains propane or propylene. The controller sets a degree of superheat of refrigerant at an entrance port of the compressor to be a value greater than or equal to 10 degrees.

Disclosed are containers (100) for cryopreserved biological samples (102), which comprise an insulated housing comprising a cavity (108) for containing at least one cryopreserved biological sample; and a sealed reservoir (106) at least partly surrounding the cavity, the sealed reservoir comprising liquified gas (120) such as liqified air, the gas being kept largely liquified by means of a heat transfer engine (112) such as a Stirling cryocooler. A valve (114) may be provided to function as both a pressure relief valve and an inlet valve. The inlet valve may be coupled to a sensor (122) for sensing a volume of liquified gas within the sealed reservoir. The container may further comprise a heat exchanger (116) coupled to the heat engine and extending into the sealed reservoir.

A refrigerant-amount determination kit includes a sensor and a processor. The sensor is mounted at least temporarily on at least one of a portion of a refrigeration cycle apparatus and the periphery of the refrigeration cycle apparatus. The refrigeration cycle apparatus is an apparatus having a refrigerant circuit that includes a compressor, a condenser, and an evaporator. The processor determines the amount of a refrigerant in the refrigerant circuit based on a detection result detected by the sensor during operation of the refrigeration cycle apparatus.

A charge-verification tool is used with a charge-verification system to diagnose and remedy a charge condition. The charge-verification tool includes a device having a controller configured to communicate with a system controller in the charge-verification system and a display configured to display measurements and instructions to an installer. The device is a user interface and is configured to provide communication between the installer and the system controller in the charge-verification system. The controller prompts the installer to input charge-verification system information including refrigeration line length and diameter. The controller receives a subcooling temperature calculated by the system controller and determines whether the subcooling temperature is between a threshold and a target subcooling temperature. The controller displays an amount of charge to add to the charge-verification system based on whether the subcooling temperature is between the threshold and the target subcooling temperature.

A system and method are described that help in alleviating charge imbalance issues, especially in HVAC systems that are operable in both heating and cooling modes. In various embodiments a compensator is attached to the liquid line of an outdoor heat exchanger. A heater is attached to the compensator. During cooling operations the heater is turned on to help drive refrigerant out of the compensator. During heating operations the heater is turned off, allowing excess refrigerant to migrate to the compensator and alleviate high pressure in the system.

A refrigeration cycle apparatus is a refrigeration cycle apparatus having a refrigerant circuit having a compressor, a condenser, a supercooler, an expansion device, and an evaporator connected by a refrigerant pipe, and configured to circulate refrigerant containing refrigerant having a temperature gradient, wherein the supercooler sets a degree of supercooling of the refrigerant, which is a temperature difference between a temperature from the condenser to a refrigerant flow inlet of the supercooler and a temperature in a refrigerant flow outlet on a downstream side of the supercooler, to be larger than the temperature gradient generated at a time of refrigerant shortage of the refrigerant between the refrigerant flow inlet and the refrigerant flow outlet of the supercooler, the refrigeration cycle apparatus including a refrigerant amount determination unit configured to compare a determination threshold value set to a value larger than the temperature gradient of the refrigerant with the degree of supercooling of the refrigerant, and determine whether or not there is a shortage of a refrigerant amount filled in the refrigerant circuit.

A refrigeration cycle apparatus includes a refrigerant circuit that includes a condenser, multiple temperature sensors that are disposed in line in a direction in which refrigerant flows in the condenser and detect refrigerant temperature of the condenser, a memory unit that stores positional information of the multiple temperature sensors, and a refrigerant amount calculation unit that calculates a refrigerant amount of the condenser based on the positional information of the multiple temperature sensors, detected temperatures of the multiple temperature sensors and a saturated liquid temperature of the refrigerant.

An air-conditioning device including multiple outdoor units and an indoor unit through a pipe includes a control section that obtains a degree of supercooling at an outlet of a supercooling circuit of each outdoor unit based on a temperature detected by a temperature sensor that detects the temperature of refrigerant having passed through the supercooling circuit of each outdoor unit, obtain a target value of the degree of supercooling based on the obtained multiple degrees of supercooling, and perform the control of increasing the rotation speed of a compressor of an outdoor unit having a higher degree of supercooling than the target value and decreasing the rotation speed of a compressor of an outdoor unit having a lower degree of supercooling than the target value such that a difference in the degree of supercooling at the outlet of the supercooling circuit of each outdoor unit is decreased.