A system of networked occupancy sensors and a thermostat that is controlled using data from the sensors. In a data network of occupancy sensors, the sensors (i) sense occupancy in a first space, such as a room within a building, and (ii) transmit data packets. Each of the data packets comprises an indication whose value is based in part on whether occupancy is sensed or not in the first space. The thermostat is situated in the first space and provides a control signal on an output line for controlling heating, ventilation, and air conditioning (HVAC), based on the temperature sensed by the thermostat. A controller unit comprises (i) a radio transceiver, capable of receiving the data packets, and (ii) a processor. The processor modifies the control signal on the output line of the thermostat, based in part on the value of the indication in the packets from the occupancy sensors.

A rotatable humidification atomizer comprises a base, on which a water tank is arranged. A downward water outlet is arranged at the bottom of the water tank, and an atomizer is fixedly arranged at the bottom. A control component is arranged in the middle of the base, and the atomizer is electrically coupled with the control component. The humidification atomizer can be rotated by arranging a rotating component between the base and the water tank. In use, the water tank cover needs to be removed as a whole when filling and changing water. The water tank on the base can be kept stationary, so that it is easy to use; the humidification atomizer sprays atomized water upward. Due to the vertical integrated design, the humidification atomizer is small and compact.

A rotatable humidification atomizer comprises a base, on which a water tank is arranged. A downward water outlet is arranged at the bottom of the water tank, and an atomizer is fixedly arranged at the bottom. A control component is arranged in the middle of the base, and the atomizer is electrically coupled with the control component. The humidification atomizer can be rotated by arranging a rotating component between the base and the water tank. In use, the water tank cover needs to be removed as a whole when filling and changing water. The water tank on the base can be kept stationary, so that it is easy to use; the humidification atomizer sprays atomized water upward. Due to the vertical integrated design, the humidification atomizer is small and compact.

A device may be configured to control a heating, ventilation, and air conditioning (HVAC) system within a building. The device includes a rotatable dial comprising a first gear; a second gear configured to engage with the first gear, wherein a rotation of the first gear causes the second gear to rotate; a magnet placed on the second gear, wherein the magnet rotates with the second gear; a sensor configured to generate an electrical signal which indicates a rotational position of the magnet, wherein the rotational position of the magnet indicates the rotational position of the second gear; and processing circuitry. The processing circuitry is configured to receive, from the sensor, the electrical signal which indicates the rotational position of the second gear; and change a temperature set point based on a change in the rotational position of the second gear.

A device may be configured to control a heating, ventilation, and air conditioning (HVAC) system within a building. The device includes a rotatable dial comprising a first gear; a second gear configured to engage with the first gear, wherein a rotation of the first gear causes the second gear to rotate; a magnet placed on the second gear, wherein the magnet rotates with the second gear; a sensor configured to generate an electrical signal which indicates a rotational position of the magnet, wherein the rotational position of the magnet indicates the rotational position of the second gear; and processing circuitry. The processing circuitry is configured to receive, from the sensor, the electrical signal which indicates the rotational position of the second gear; and change a temperature set point based on a change in the rotational position of the second gear.

A heating, ventilation, and air conditioning (HVAC) system includes a blower assembly including a blower motor; and an electronically commutated motor (ECM) controller in electrical communication with the blower motor, the ECM controller including: a rectifier electrically connected to an alternating current (AC) input source, the rectifier being configured to receive AC electricity from the AC input source and convert the AC electricity to direct current (DC) electricity; a DC electrical circuit including a first DC electrical circuit loop and a second DC electrical circuit loop, the rectifier being configured to circulate the DC electricity through the DC electrical circuit; and a relay located within the first DC electrical circuit loop, the relay being configured to open to break the first DC electrical circuit loop and close to complete the first DC electrical circuit loop in order to reduce standby power consumption of the ECM controller.

Tools and techniques are described to automate line testing when wiring devices (such as equipment and sensors) to controllers. Controllers have access to databases of the devices that are controlled by them, including wiring diagrams and protocols, such that the controller can automatically check that each wire responds correctly to stimulus from the controller. After testing, a reporting device rapidly shows the results of the line testing.

Tools and techniques are described to automate line testing when wiring devices (such as equipment and sensors) to controllers. Controllers have access to databases of the devices that are controlled by them, including wiring diagrams and protocols, such that the controller can automatically check that each wire responds correctly to stimulus from the controller. After testing, a reporting device rapidly shows the results of the line testing.

A method of monitoring an air filter in a heating, ventilation, and air conditioning (HVAC) system that includes operating a blower motor at a desired torque; monitoring a horsepower of the blower motor over a selected time period when the blower motor is operating at the desired torque; determining a moving average of the horsepower of the blower motor over the selected time period; detecting when the moving average drops below an established baseline moving average by a selected percentage; and activating a notification to check or change the air filter of the HVAC system.

A communication circuit includes first and second communication nodes including first and second control chips, respectively, and first and second communication chips connected to the first and second control chips, respectively. The first and second communication chips are connected to each other through first and second signal lines, and are configured to transmit a differential signal. The first communication chip includes an output port to output a level signal obtained from the differential signal to the first control chip. The communication circuit further includes a voltage division assembly connected to the first and second signal lines, and configured to cause a voltage value of the first signal line to be higher than that of the second signal line when the first and second signal lines are in idle state. The first control chip includes a detection port connected to the output port to acquire the level signal.