A method of training a comfort model used for controlling a heating, ventilation, and air-conditioning, HVAC, system. The method includes: a user device providing a plurality of user feedbacks, each of the plurality of user feedbacks is provided at a respective point in time and describes a thermal comfort of a user using the user device; at each point in time associated with the plurality of user feedbacks, each of a plurality of HVAC devices detecting running parameters; and for each of the plurality of user feedbacks: inputting the running parameters of each of the plurality of HVAC devices detected at the respective point in time into the comfort model to generate a predicted thermal comfort, determining a loss value by comparing the predicted thermal comfort with the thermal comfort described by the respective user feedback, and training the comfort model to reduce the loss value.

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 closed-loop temperature controller employing at least two sensors: a control temperature sensor and a safety sensor at the heat-transfer element. The heat-generating element is separated from the controlled mass/volume by a transport delay so that the mass or volume that is being heated or cooled is located in a vessel which is located remotely from the heat-transfer unit. Thermally conducting fluid flows through a conduit that connects the heat-transfer unit to the vessel. Upon fluid flow interruption or control sensor removal, the temperature controller quickly detects thermal runaway before the safety sensor has reached the critical temperature. In heated systems, the temperature controller will therefore minimize direct damage and/or overshoot damage caused by excessive heat. It will also maintain the heater's output at an elevated, but non-damaging level to enable a fast recovery to the original setpoint temperature after the nonlinearity subsides.

An air conditioning control system includes a plurality of remote control terminals and a server. The plurality of remote control terminals each calculates a time required for a user of the remote control terminal to return to a building from outside the building, and transmits information indicating the time required to the server. The server calculates an estimated time when a user who returns to the building first among the plurality of users returns to the building on the basis of the time required, and transmits a command for changing air conditioning setting to an air conditioner in stages from a time when the estimated time is calculated to the estimated time calculated.

An air conditioning control system includes a plurality of remote control terminals and a server. The plurality of remote control terminals each calculates a time required for a user of the remote control terminal to return to a building from outside the building, and transmits information indicating the time required to the server. The server calculates an estimated time when a user who returns to the building first among the plurality of users returns to the building on the basis of the time required, and transmits a command for changing air conditioning setting to an air conditioner in stages from a time when the estimated time is calculated to the estimated time calculated.

A method of controlling a heating, ventilation, and air-conditioning, HVAC, system. The method includes: controlling indoor environmental conditions using the HVAC system, detecting a load of the HVAC system, inputting detected indoor environmental conditions and detected outdoor environmental conditions into a load prediction model to generate a predicted load, and training the load prediction model to reduce a difference between the predicted load and the detected load of the HVAC system; determining requested indoor environmental conditions associated with a future time period; determining predicted outdoor environmental conditions within the future time period using a weather forecast; inputting the requested indoor environmental conditions and the predicted outdoor environmental conditions into the trained load prediction model to determine a predicted load for the future time period; controlling the HVAC system to reduce a load of the HVAC system within the future time period using the determined predicted load.

A fluid flow device that can measure and control a flow of a fluid is described. Various procedures, including measuring, controlling, balancing, or calibration procedures can leverage differential pressure measurement. These differential pressure measurements can be measured across the fluid flow device such that a first pressure measurement is taken upstream of the fluid flow device while a second pressure measurement is taken downstream of the fluid flow device. Moreover, one or more of the various pressure measurements, and in particular the downstream pressure measurement, can be performed at stagnation zone where the flow has stagnated. Such can provide significant amplification and/or turndown capabilities.

Methods for controlling temperature in a conditioned enclosure such as a dwelling are described that include an “auto-away” and/or “auto-arrival” feature for detecting unexpected absences which provide opportunities for significant energy savings through automatic adjustment of the setpoint temperature. According to some preferred embodiments, when no occupancy has been detected for a minimum time interval, an “auto-away” feature triggers a changes of the state of the enclosure, and the actual operating setpoint temperature is changed to a predetermined energy-saving away-state temperature, regardless of the setpoint temperature indicated by the normal thermostat schedule. The purpose of the “auto away” feature is to avoid unnecessary heating or cooling when there are no occupants present to actually experience or enjoy the comfort settings of the schedule, thereby saving energy.

Methods for controlling temperature in a conditioned enclosure such as a dwelling are described that include an “auto-away” and/or “auto-arrival” feature for detecting unexpected absences which provide opportunities for significant energy savings through automatic adjustment of the setpoint temperature. According to some preferred embodiments, when no occupancy has been detected for a minimum time interval, an “auto-away” feature triggers a changes of the state of the enclosure, and the actual operating setpoint temperature is changed to a predetermined energy-saving away-state temperature, regardless of the setpoint temperature indicated by the normal thermostat schedule. The purpose of the “auto away” feature is to avoid unnecessary heating or cooling when there are no occupants present to actually experience or enjoy the comfort settings of the schedule, thereby saving energy.

A relay device and a multi-split control system that achieve reliable communication between an outdoor air conditioning unit and multiple indoor units under the condition that the length of a communication bus is limited. The system expands the communication distance by a cascade path formed by a plurality of relay devices. The cascade path transmits control signals sent by a master control device/a specific slave control device (i.e. a slave control device communicating with the master control device or certain relay device) to corresponding slave control devices one by one, and the corresponding slave control devices transmit the signals to the master control device/specific slave control device according to a response signal fed back by the control signal, where the relay devices may respectively communicate with a source node device and a destination node device on the basis of the master-slave type communication mode.