A gas detector is provided and includes a gas detector element, electronics to interface with the gas detector element and an enclosure configured to expose the gas detector element to an exterior and to form an electronics housing area in which the electronics are disposed whereby the electronics are isolated from the exterior.

An HVAC system includes a reversing valve configured to receive compressed refrigerant and direct the refrigerant based on an operating mode. One or more suction-side sensors measure suction-side properties associated with refrigerant, including a suction-side temperature and a suction-side pressure. One or more liquid-side sensors measure liquid-side properties associated with the refrigerant. A controller monitors the suction-side pressure and liquid-side pressure and determines a ratio of the liquid-side pressure to the suction-side pressure. The controller further determines whether the suction-side temperature has an increasing trend. If the suction-side temperature has the increasing trend, the reversing valve is determined to be in an equalizing configuration. The equalizing configuration corresponds to a configuration in which the refrigerant provided from the outlet of the compressor is directed to the inlet of the compressor without first being directed to other components of the HVAC system.

Example implementations relate to a leak mitigation (LM) system. The LM system may include a collection tank, a first valve unit coupled to the collection tank, a second valve unit coupled to a cooling loop carrying a coolant, and an LM pump coupled between the first valve unit and the second valve unit. Moreover, the leak mitigation system may also include a controller operatively coupled to the first valve unit, the second valve unit, and the LM pump to operate, in an event of a leak of the coolant from the cooling loop, the first valve unit, the second valve unit, and the LM pump to transfer at least a portion of the coolant to the collection tank from the cooling loop via the second valve unit and the first valve unit.

Technologies described herein are directed to isolating or insulating at least portions of an evaporator coil within a climate control unit (CCU) of a TCCS so as to reduce or even eliminate adverse effects caused by a leaked working fluid. Such adverse effects may include a threat of ignition, asphyxiation of occupants, damage to cargo, and other harmful effects caused by emission of a noxious gas. A leak isolation structure is provided to isolate evaporator tubes of an evaporator coil from at least one of a plurality of turns of the evaporator coil.

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.

An HVAC system includes a high-pressure subsystem and a low-pressure subsystem. After determining that refrigerant leak diagnostics should be performed, a controllable valve is closed between a condenser and compressor of the HVAC system. The compressor then operates until a predetermined input refrigerant pressure is reached. After the predetermined input refrigerant pressure is reached, operation of the compressor is stopped. After stopping operation of the compressor and waiting at least a predetermined wait time, the pressure in the low-pressure subsystem of the HVAC system is monitored. A rate of change of the pressure in the low-pressure subsystem is determined. If the rate of change is negative and a magnitude of the rate of change is greater than a threshold value, a leak location is determined to be in the low-pressure subsystem.

An air conditioner including: a compressor; a heat exchanger fluidly connected to the compressor; a pressure sensor provided in a first flow path connecting an outlet of the compressor to an inlet of the first heat exchanger; a temperature sensor provided in a second flow path connected to an outlet of the heat exchanger; and a processor connected to the compressor, the pressure sensor, and the temperature sensor. The processor configured to: acquire a reference index value based on a first reference pressure measured by the pressure sensor and a first reference temperature measured by the temperature sensor, acquire a measurement index value based on a first measurement pressure measured by the pressure sensor and a first measurement temperature measured by the temperature sensor, and display a shortage of a refrigerant of the air conditioner based on the reference index value and the measurement index value.

When the anomaly determination mode starts, the controller brings the decompressor into the first decompression amount state, and operates a compressor at a first speed. The controller is configured to store a value of the related physical quantity measured by the detector at a time point at which a first time elapses from a start of the anomaly determination mode, as a first measurement value, and thereafter switch the decompressor to the second decompression amount state from the first decompression amount state, store a value of the related physical quantity measured by the detector after the decompressor is switched to the second decompression amount state from the first decompression amount state, as a second measurement value, and determine that there is anomaly in the refrigerant circuit when a value obtained by subtracting the first measurement value from the second measurement value is larger than a first anomaly determination value.

A system for analyzing a heating, ventilation, and air conditioning (HVAC) system includes: a processor; a display device controlled by the processor; a wireless communication module configured to receive a plurality of measurements from a plurality of different HVAC test instruments arranged to take measurements from the HVAC system, each of the HVAC test instruments providing one or more of the measurements; and a memory having instructions stored thereon where, when the instructions are executed by the processor, cause the processor to: receive the measurements from the different HVAC test instruments via the wireless communication module; convert the measurements to a common format; store the measurements in the common format in the memory; and display the measurements on the display device.

A method and system for improving energy efficiency of a refrigeration system include system components such as a condenser, one or more expansion valves, an evaporator, one or more compressors, and a system controller electrically coupled to the one or more of the system components, according to one embodiment. The system controller is configured to selectively actuate, directly or indirectly, the one or more expansion valves, the condenser, and/or the one or more compressors, at least partially based on temperatures and/or pressures of the system fluid at various points of the system, to control a temperature of a refrigerated area.