Devices, methods, and systems for determining the cause of a fault in a heating, ventilation, and air conditioning (HVAC) system are described herein. One device includes a memory, and a processor configured to execute executable instructions stored in the memory to receive operational data associated with an HVAC system, receive control logic associated with a controller of the HVAC system, determine a cause of a fault occurring in the HVAC system based, at least in part, on the operational data associated with the HVAC system and the control logic of the controller of the HVAC system, and provide the cause of the fault occurring in the HVAC system to a user.

Devices, methods, and systems for determining the cause of a fault in a heating, ventilation, and air conditioning (HVAC) system are described herein. One device includes a memory, and a processor configured to execute executable instructions stored in the memory to receive operational data associated with an HVAC system, receive control logic associated with a controller of the HVAC system, determine a cause of a fault occurring in the HVAC system based, at least in part, on the operational data associated with the HVAC system and the control logic of the controller of the HVAC system, and provide the cause of the fault occurring in the HVAC system to a user.

Airborne contaminant detection and localization systems include an HVAC system having a duct, a first vent connected to a first indoor space, and a second vent fluidly connected to a second indoor space, with the second vent being downstream from the first vent in a flow direction along the duct. A monitoring system includes a first and second sensor elements arranged proximate the first and second vents, respectively, the sensor elements configured to detect one or more airborne contaminants. A central unit receives sensor data from the sensor elements. The central unit includes information regarding a location of each of the sensor elements within the duct. The central unit determines the presence and intensity of an airborne contaminant in the duct from the sensor data and establishes a detection zone that includes a portion of the vent having a highest detected intensity of the airborne contaminant.

A program for light commercial building system (LCBS) solutions. Solutions and other systems may incorporate lightweight alerting service, auto-adjustment of gateway poll rates based on the needs of various consuming applications, detecting loss of space comfort control in a heating, ventilation and air conditioning (HVAC) system, HVAC capacity loss alerting using relative degree days and accumulated stage run time with operational equivalency checks, and HVAC alerting for loss of heat or cool capacity using delta temperature and dependent system properties. Also, incorporated may be triggering s subset of analytics by automatically inferring HVAC equipment details from controller configuration details, ensuring reliability of analytics by retaining logical continuity of HVAC equipment operational data even when controllers and other parts of the system are replaced, and an LCBS gateway with workflow and mechanisms to associate to a contractor account.

Methods and systems for controlling a building. An illustrative method includes receiving sensor data from one or more sensors of the building, using the received sensor data to control one or more building management components to control one or more environmental conditions within the building, normalizing the sensor data and storing the normalized sensor data, comparing the normalized sensor data with normalized sensor data from one or more other buildings to identify one or more anomalies associated the building, and providing a recommended action to improve at least one of the one or more identified anomalies of the building.

Methods and systems for controlling a building. An illustrative method includes receiving sensor data from one or more sensors of the building, using the received sensor data to control one or more building management components to control one or more environmental conditions within the building, normalizing the sensor data and storing the normalized sensor data, comparing the normalized sensor data with normalized sensor data from one or more other buildings to identify one or more anomalies associated the building, and providing a recommended action to improve at least one of the one or more identified anomalies of the building.

A communication kit comprising a communication module configured to communicate with a thermostat, an indoor unit, and an outdoor unit; and a controller configured to generate an operation signal to be transmitted to the indoor unit and the outdoor unit, based on a signal received from the thermostat, wherein the controller is configured to determine an operation mode of the indoor unit and the outdoor unit based on an indoor temperature when a backup function of the thermostat is executed.

A communication kit comprising a communication module configured to communicate with a thermostat, an indoor unit, and an outdoor unit; and a controller configured to generate an operation signal to be transmitted to the indoor unit and the outdoor unit, based on a signal received from the thermostat, wherein the controller is configured to determine an operation mode of the indoor unit and the outdoor unit based on an indoor temperature when a backup function of the thermostat is executed.

An air conditioner unit includes a variable speed compressor for circulating refrigerant through refrigeration loop and a controller configured to initiate an operating cycle, start a compressor transition timer, and determine an unfiltered compressor speed. The unfiltered compressor speed is fixed based on the selected operating mode until the compressor transition timer reaches a predetermined transition delay time, after which the unfiltered compressor speed is determined using a closed loop feedback control algorithm. The controller is further configured to operating the variable speed compressor at a target compressor speed that is modified from the unfiltered compressor speed based on the identification of a speed modification condition, such as a dehumidification deficiency a speed restriction, or the identification of one or more resonance avoidance zones.

An air conditioner unit includes a variable speed compressor for circulating refrigerant through refrigeration loop and a controller configured to initiate an operating cycle, start a compressor transition timer, and determine an unfiltered compressor speed. The unfiltered compressor speed is fixed based on the selected operating mode until the compressor transition timer reaches a predetermined transition delay time, after which the unfiltered compressor speed is determined using a closed loop feedback control algorithm. The controller is further configured to operating the variable speed compressor at a target compressor speed that is modified from the unfiltered compressor speed based on the identification of a speed modification condition, such as a dehumidification deficiency a speed restriction, or the identification of one or more resonance avoidance zones.