Abstract: In an embodiment, a query system sends compact code to a database service for expansion of the compact code to partially-expanded code and expanded code. In an embodiment, a hash value is generated based on the partially-expanded code and indexed in memory with the expanded code. In an embodiment, a hash value is received as part of a command and expanded code is identified based on the hash value and sent to a database service.

Abstract: Embodiments of the present disclosure are directed to a controller for a heating, ventilation, and/or air conditioning (HVAC) system. The controller is configured to operate in a first defrost mode or a second defrost mode, determine that feedback from a first sensor of the HVAC system is unavailable, receive feedback from a second sensor of the HVAC system, and operate the HVAC system in the second defrost mode instead of the first defrost mode in response to unavailability of the feedback from the first sensor and based on the feedback from the second sensor.

Abstract: In an embodiment, a query system sends compact code to a database service for expansion of the compact code to partially-expanded code and expanded code. In an embodiment, a hash value is generated based on the partially-expanded code and indexed in memory with the expanded code. In an embodiment, a hash value is received as part of a command and expanded code is identified based on the hash value and sent to a database service.

Abstract: A heating, ventilation, and air conditioning (HVAC) system includes a primary heat transfer circuit having a first heat exchanger fluidly coupled to an ambient environment and a compressor fluidly coupled to the first heat exchanger and configured to circulate a refrigerant through the primary heat transfer circuit. The HVAC system also includes a secondary heat transfer circuit having a second heat exchanger fluidly coupled to a thermal load and a pump fluidly coupled to the second heat exchanger and configured to circulate a heat transfer fluid through the secondary heat transfer circuit, where the heat transfer fluid is a non-volatile or inert fluid.

Abstract: A control system for a heating, ventilation, and/or air conditioning (HVAC) system includes a controller. The controller is configured to control the HVAC system to condition an air flow based on first feedback from a first sensor of the HVAC system, receive second feedback from a second sensor of the HVAC system, and control the HVAC system to condition the air flow based on the second feedback instead of the first feedback when the first feedback from the first sensor being no longer available. The first feedback is indicative of a first operating parameter of the HVAC system, and the second feedback is indicative of a second operating parameter of a refrigerant flowing through the HVAC system.

Abstract: A heating, ventilation, and air conditioning (HVAC) system includes a heat exchanger configured to receive a working fluid and place the working fluid in a heat exchange relationship with an air flow directed across the heat exchanger, a switch configured to detect an operating parameter of the HVAC system, where the switch is configured to interrupt operation of the HVAC system in response to detection of a first value of the operating parameter greater than an operating parameter limit value, and a sensor configured to detect the operating parameter of the HVAC system.

Abstract: Embodiments of the present disclosure are directed to a controller for a heating, ventilation, and/or air conditioning (HVAC) system. The controller is configured to operate in a first defrost mode or a second defrost mode, determine that feedback from a first sensor of the HVAC system is unavailable, receive feedback from a second sensor of the HVAC system, and operate the HVAC system in the second defrost mode instead of the first defrost mode in response to unavailability of the feedback from the first sensor and based on the feedback from the second sensor.

Abstract: A control system for a heating, ventilation, and/or air conditioning (HVAC) system includes a controller. The controller is configured to control the HVAC system to condition an air flow based on first feedback from a first sensor of the HVAC system, receive second feedback from a second sensor of the HVAC system, and control the HVAC system to condition the air flow based on the second feedback instead of the first feedback when the first feedback from the first sensor being no longer available. The first feedback is indicative of a first operating parameter of the HVAC system, and the second feedback is indicative of a second operating parameter of a refrigerant flowing through the HVAC system.

Abstract: A control system for a heating, ventilation, and/or air conditioning (HVAC) system includes a controller. The controller is configured to control the HVAC system to condition an air flow based on first feedback from a first sensor of the HVAC system, receive second feedback from a second sensor of the HVAC system, and control the HVAC system to condition the air flow based on the second feedback instead of the first feedback when the first feedback from the first sensor being no longer available. The first feedback is indicative of a first operating parameter of the HVAC system, and the second feedback is indicative of a second operating parameter of a refrigerant flowing through the HVAC system.

Abstract: Embodiments of the present disclosure are directed to a controller for a heating, ventilation, and/or air conditioning (HVAC) system. The controller is configured to operate in a first defrost mode or a second defrost mode, determine that feedback from a first sensor of the HVAC system is unavailable, receive feedback from a second sensor of the HVAC system, and operate the HVAC system in the second defrost mode instead of the first defrost mode in response to unavailability of the feedback from the first sensor and based on the feedback from the second sensor.

Abstract: A control system for a heating, ventilation, and/or air conditioning (HVAC) system includes a controller. The controller is configured to control the HVAC system to condition an air flow based on first feedback from a first sensor of the HVAC system, receive second feedback from a second sensor of the HVAC system, and control the HVAC system to condition the air flow based on the second feedback instead of the first feedback when the first feedback from the first sensor being no longer available. The first feedback is indicative of a first operating parameter of the HVAC system, and the second feedback is indicative of a second operating parameter of a refrigerant flowing through the HVAC system.

Abstract: The present disclosure relates to a refrigerant leak detection and mitigation system of a heating, ventilating, and air conditioning (HVAC) unit. The refrigerant leak detection and mitigation system includes a controller configured to determine a plurality of parameters correlated to refrigerant leak conditions based on data from a plurality of sensors. The controller is also configured to determine a probability of a refrigerant leak in the HVAC unit based on the plurality of parameters. Additionally, the controller is configured to provide a control signal to modify operation of the HVAC unit in response to comparison of the probability with a threshold value.

Abstract: A system and a method are provided for returning oil in a heating, ventilation, and air conditioning (HVAC) system by determining when an ambient zone temperature is equal to or less than a temperature limit and reversing a direction of refrigerant flow of the HVAC system based on the length of time. Also, a system and a method are provided for monitoring the length of operation in a first and a second heating mode and for reversing a direction of refrigerant flow based on the length of time operation occurs in the first and second heating modes. A system and a method having a first compressor, a first heating mode, a second heating mode, a defrost mode, and a controller is disclosed. The controller selectively controls initiation of the defrost mode in response to an HVAC system operating in a heating mode of operation for a predetermined amount of time.

Abstract: A system and a method are provided for monitoring a condition and selectively executing a certification defrost algorithm for a heating, ventilation, and air conditioning (HVAC) system in response to the status of the monitored condition. A system and a method are provided for selectively operating a certification defrost algorithm in parallel to a field defrost algorithm. A system and a method are also provided for causing a controller to execute a first algorithm and for causing the controller to selectively execute a second algorithm while also executing the first algorithm where each of the first algorithm and the second algorithm are configured to selectively cause the HVAC system to operate in a defrost mode.

Abstract: A system and a method are provided for returning oil in a heating, ventilation, and air conditioning (HVAC) system by determining when an ambient zone temperature is equal to or less than a temperature limit and reversing a direction of refrigerant flow of the HVAC system based on the length of time. Also, a system and a method are provided for monitoring the length of operation in a first and a second heating mode and for reversing a direction of refrigerant flow based on the length of time operation occurs in the first and second heating modes. A system and a method having a first compressor, a first heating mode, a second heating mode, a defrost mode, and a controller is disclosed. The controller selectively controls initiation of the defrost mode in response to an HVAC system operating in a heating mode of operation for a predetermined amount of time.

Abstract: A system and method is provided for monitoring a system pressure to infer whether a high pressure cut out (HPCO) switch has opened disabling a heating, ventilating, and air conditioning (HVAC) compressor. A system and method are also provided for determining whether to disable the heating, ventilating, and air conditioning (HVAC) compressor based on a status of a low pressure cut out (LPCO) switch, an ambient temperature, and system mode state. The systems and methods may be used interchangeably with the appropriate adjustments to decision limits, such as where the LPCO may be monitored to infer status and the HPCO status may be directly used with temperature and system mode state.

Abstract: A system and a method are provided for powering up a heating, ventilation, and air conditioning (HVAC) system and operating a sump heater for a compressor for a first predetermined period of time in response to the HVAC system being powered up. A heating, ventilation, and air conditioning system and a method for controlling the system are provided. The HVAC system includes a compressor, a sump heater associated with the compressor, and a controller configured to control the compressor and the sump heater so that the sump heater is not operated while the compressor is operated.

Abstract: A system and method is provided for monitoring a system pressure to infer whether a high pressure cut out (HPCO) switch has opened disabling a heating, ventilating, and air conditioning (HVAC) compressor. A system and method are also provided for determining whether to disable the HVAC compressor based on a status of a low pressure cut out (LPCO) switch, an ambient temperature, and system mode state. The systems and methods may be used interchangeably with the appropriate adjustments to decision limits, such as where the LPCO may be monitored to infer status and the HPCO status may be directly used with temperature and system mode state.

Abstract: A system and a method are provided for monitoring a condition and selectively executing a certification defrost algorithm for a heating, ventilation, and air conditioning (HVAC) system in response to the status of the monitored condition. A system and a method are provided for selectively operating a certification defrost algorithm in parallel to a field defrost algorithm. A system and a method are also provided for causing a controller to execute a first algorithm and for causing the controller to selectively execute a second algorithm while also executing the first algorithm where each of the first algorithm and the second algorithm are configured to selectively cause the HVAC system to operate in a defrost mode.

Abstract: A system and a method are provided for powering up a heating, ventilation, and air conditioning (HVAC) system and operating a sump heater for a compressor for a first predetermined period of time in response to the HVAC system being powered up. A heating, ventilation, and air conditioning system and a method for controlling the system are provided. The HVAC system includes a compressor, a sump heater associated with the compressor, and a controller configured to control the compressor and the sump heater so that the sump heater is not operated while the compressor is operated.