An HVAC system includes a compressor, condenser, and evaporator. A sensor measures a value associated with the refrigerant in the condenser or the evaporator, and a controller is communicatively coupled to the compressor and the sensor. The controller determines, based on an operational history the compressor, that pre-requisite criteria are satisfied for entering a sensor validation mode. After determining the pre-requisite criteria are satisfied, an initial sensor measurement value is determined. Following determining the initial sensor measurement value, the compressor is operated according to a sensor-validation mode. Following operating the compressor according to the sensor-validation mode for at least a minimum time, a current sensor measurement value is determined. The controller determines whether validation criteria are satisfied for the current sensor value. In response to determining that the validation criteria are satisfied, the controller determines that the sensor is validated.

Methods and systems are provided for an air conditioning system. An example method of determining current through a compressor suction valve in a vehicle air conditioning (AC) system is provided, the AC system comprises an evaporator fan and the method includes determining the speed of the evaporator fan and determining the current through the suction valve based on the speed of the evaporator fan.

An HVAC system with a refrigerant gas sensor is provided. In one embodiment, an HVAC system includes a heat exchanger coil installed within a housing. The heat exchanger coil is operable to exchange heat with air in the housing via a refrigerant passing through the heat exchanger coil. The system also includes an HVAC sensor assembly installed within the housing. The HVAC sensor assembly includes a refrigerant gas sensor and an orientation sensor positioned to detect an orientation of the refrigerant gas sensor. The HVAC system may also or instead include a position sensor to detect the position of the refrigerant gas sensor within the system. Additional systems, devices, and methods are also disclosed.

A heat exchange system and a method for determining whether flow of cooling medium passing through a heat exchanger is too low. The heat exchange system includes a refrigerant flow path in which refrigerant circulates; a cooling medium flow path in which cooling medium circulates; and a heat exchanger connected to both the refrigerant flow path and the cooling medium flow path so that the refrigerant and the cooling medium exchange heat in the heat exchanger. The heat exchange system includes a first temperature sensor arranged at a cooling medium inlet of the heat exchanger, a second temperature sensor at a cooling medium outlet of the heat exchanger, and a controller in communication with the first temperature sensor and the second temperature sensor. The controller is configured to determine whether the flow of cooling medium in the heat exchanger is too low based on a temperature difference.

A method for suppressing the blockage of a miniature Joule-Thomson cryocooler based on a photothermal effect includes: determining form and temperature of a trace impurity contained in a working medium of the cryocooler according to an operating condition of the cryocooler, and selecting an optimal wavelength of an electromagnetic wave based on the form and temperature of the impurity and a peak of absorption spectrum of the impurity to electromagnetic waves; estimating, via a prediction model of input power of the electromagnetic wave, an initial value of input power corresponding to the optimal wavelength; and emitting an electromagnetic wave with the power W by a laser capable of generating the optimal wavelength in a direction perpendicular to a passage of a throttle in the cryocooler to eliminate the impurity in the passage of the throttle.

A monitoring and/or control device for an environmental control unit such as a heat pump determines the performance status and whether maintenance is required of a component of the unit for example a compressor during operation of the component. The device includes sensors configured to be situated relative to the compressor so as to receive and signal data from the compressor during operation of the component. In some embodiments, the device includes a vibration detector and a controller coupled to the vibration detector. The controller is configured to (i) receive electrical signals from the vibration detector, (ii) compare the electrical signals to a reference signal, (iii) determine the performance characteristic of the component based on the results of the comparison, and (iv) output a signal corresponding to the performance characteristic of the component to a user display. The controller may also request maintenance and/or order parts automatically.

The invention discloses a multi-split system with partitioned control. An output end of a compressor is in communication with first interfaces of a first four-way valve, a second four-way valve, and a third four-way valve respectively, a third interface of the first four-way valve is in communication with one end of an outdoor heat exchanger, a second interface of the second four-way valve is in communication with one end of one indoor unit set therein, a third interface of the third four-way valve is in communication with one end of the other indoor unit set, and the other end of the outdoor heat exchanger and the other ends of the indoor unit sets are in communication with each other in a convergence manner; the remaining interfaces of the second four-way valve and the third four-way valve are all in communication with an air return end of the compressor.

A safety system for a heat pump system includes a plurality of valve units each having refrigerant pipe portions with control valves, a refrigerant leakage detector, and a casing accommodating the valves and the refrigerant leakage detector and formed with first and second openings. The safety system further includes a connection structure connecting the internal spaces of the casings via the first and second openings, and a discharge structure connected to the connection structure or one of the casings and configured to discharge air from the internal space of the casing in which a refrigerant leakage has occurred. The casing has first and second lateral faces facing different directions, and the first opening is formed in the first lateral face and the second opening is formed in the second lateral face.

A refrigerated display case having a housing defining a temperature controlled space and a refrigeration system coupled to the housing is provided. The refrigeration system is configured to be operable to affect a temperature of the temperature controlled space. The refrigeration system includes an actuator, a controller, and a sensor. The controller is configured to continuously update a stored position of the actuator based on measurement of an electric current provided to the actuator, retrieve the stored position after a power failure, and restart control based on the stored position of the actuator. The sensor is configured to communicate with the controller.

A lock assembly includes at least a lock component, a lock member, and a bracket. The lock component is securable to a load cell. The lock member is configured to move into a first position to provide an unlocked state in which the lock member is disengaged from the lock component. In the unlocked state, the load cell is physically unsecured from the lock member and enabled to operate. The lock member is configured to move into a second position to provide a locked state in which the lock member is engaged with the lock component. In the locked state, the load cell is physically secured to the lock member via the lock component. The bracket is configured to support the lock member in relation to the lock component.