A system includes a compressor driven by a motor. A condenser receives working fluid from the compressor. An evaporator is in fluid communication with the condenser and the compressor. A first sensor produces a first signal, and a second sensor produces a second signal. A processing circuitry processes the first signal and the second signal to determine a new baseline freeze time. The processing circuitry determines the new baseline freeze time for a predetermined time following an installation event, a service event, or a power outage of the compressor.

Refrigeration apparatus R that includes a refrigerant circuit composed of compressor 11, gas cooler 28, electric expansion valve 39, and evaporator 41 includes: electric expansion valve 33; tank 36; split heat exchanger 29; electric expansion valve 43; electric expansion valve 47; auxiliary circuit 48; main circuit 38; low-pressure sensor 51; and control apparatus 57, in which control apparatus 57 regulates the pressure of the refrigerant after the refrigerant flows out of tank 36 but before flows into electric expansion valve 39 to be a first constant pressure when the pressure detected by low-pressure sensor 51 is smaller than a specified pressure, and regulates the pressure of the refrigerant to be a second constant pressure smaller than the first constant pressure when the pressure detected by low-pressure sensor 51 is larger than the specified pressure.

A heat-pump circuit may include an indoor heat exchanger, an outdoor heat exchanger, a compressor adapted to circulate a working fluid between the indoor and outdoor heat exchangers, and an expansion device disposed between the indoor and outdoor heat exchangers. A monitor for the heat-pump system may include a return-air temperature sensor, a supply-air temperature sensor, and a processor. The return-air temperature sensor may be adapted to measure a first air temperature of air upstream of the indoor heat exchanger. The supply-air temperature sensor may be adapted to measure a second air temperature of air downstream of the indoor heat exchanger. The processor may be in communication with the return-air temperature sensor and the supply-air temperature sensor. The processor may be programmed to determine a working-fluid-charge condition of the heat-pump system based on the first and second air temperatures.

A refrigeration cycle apparatus includes a refrigerant circuit connecting a compressor, a heat source-side heat exchanger, an expansion device, and a use-side heat exchanger to each other by connecting pipes, an outside air temperature sensor configured to detect an outside air temperature, and a controller configured to operate the refrigeration cycle apparatus and to switch between a normal operation mode for controlling the refrigerant circuit based on an operation load of the use-side heat exchanger and a refrigerant amount determining mode for determining whether or not an amount of refrigerant in the refrigerant circuit is appropriate. The controller is configured to switch the normal operation mode to the refrigerant amount determining mode when the outside air temperature detected by the outside air temperature sensor is within a set temperature range.

An air conditioner is provided, which is capable of accurately determining appropriateness of a refrigerant amount in a refrigerating cycle. A control apparatus is configured to: stop a cooling operation; set an expansion valve to a fully-closed state and, at the same time, switch the selector valve to change the direction, in which a refrigerant flows, to an opposite direction; operate a compressor to perform a refrigerant recovery operation, in which a refrigerant contained in an outdoor heat exchanger is recovered by an indoor heat exchanger; and determine the appropriateness of a refrigerant amount in a refrigerating cycle, based on at least one of a time required for recovering the refrigerant, a pressure change in a refrigerant suctioned by the compressor, and temperature of the refrigerant discharged from the compressor during the refrigerant recovery operation.

An adsorber includes: a heat-medium pipe through which a heat medium flows; an adsorbent layer having an adsorbent that adsorbs a vapor-phase refrigerant located outside the heat-medium pipe by being cooled by the heat medium, and further desorbs the adsorbed refrigerant by being heated; and a heat-transfer member that transfers heat between the heat-medium pipe and the adsorbent. In the adsorber in which the heat-transfer member and the adsorbent are integrally formed, an adsorbent filling ratio is set at 70% or less when the adsorbent filling ratio is defined as a value obtained by dividing a filling density of the adsorbent filled in the adsorbent layer by a true density abs of particles of the adsorbent. For example, the adsorber may be suitably used for an adsorption refrigerator.

A refrigeration cycle apparatus is provided with a refrigerant circuit, a refrigerant tank circuit, and a degassing pipe. The refrigerant circuit is configured by connecting a compressor, a flow path switching apparatus, a first heat exchanger, a decompressing apparatus, and a second heat exchanger. The refrigerant tank circuit is connected to the first and second heat exchangers in parallel with the decompressing apparatus. The degassing pipe has a first end and a second end. The flow path switching apparatus is configured to switch a flow of refrigerant discharged from the compressor to any of the first and second heat exchangers. The refrigerant tank circuit contains a refrigerant tank. The degassing pipe has the first end connected to the refrigerant tank and has the second end connected to at least any of the refrigerant circuit and the refrigerant tank circuit.

Provided is a air conditioner including high-and-low-pressure gas pipe expansion valves each of which is provided to a corresponding one of the cooling-heating switching units and adjusts feeding of high-temperature and high-pressure gas refrigerant to the corresponding indoor unit; and a refrigeration cycle controller which adjusts a valve opening degree of the high-and-low-pressure gas pipe expansion valve of the cooling-heating switching unit connected to one of the indoor units which is not in heating operation, in accordance with a determination result on excess or deficiency of refrigerant in a refrigeration cycle.

A heat-pump circuit may include an indoor heat exchanger, an outdoor heat exchanger, a compressor adapted to circulate a working fluid between the indoor and outdoor heat exchangers, and an expansion device disposed between the indoor and outdoor heat exchangers. A monitor for the heat-pump system may include a return-air temperature sensor, a supply-air temperature sensor, and a processor. The return-air temperature sensor may be adapted to measure a first air temperature of air upstream of the indoor heat exchanger. The supply-air temperature sensor may be adapted to measure a second air temperature of air downstream of the indoor heat exchanger. The processor may be in communication with the return-air temperature sensor and the supply-air temperature sensor. The processor may be programmed to determine a working-fluid-charge condition of the heat-pump system based on the first and second air temperatures.

A system includes a compressor driven by a motor. A condenser receives working fluid from the compressor. An evaporator is in fluid communication with the condenser and the compressor. A first sensor produces a first signal, and a second sensor produces a second signal. A processing circuitry processes the first signal and the second signal to determine a new baseline freeze time. The processing circuitry determines the new baseline freeze time for a predetermined time following an installation event, a service event, or a power outage of the compressor.