Embodiments of the present disclosure include a drive belt tensioner configured to adjust tension in a drive belt of a blower assembly for a heating, ventilation, and/or air conditioning (HVAC) system. The drive belt tensioner includes a mounting bracket configured to couple directly to a blower housing that is configured to house a blower of the blower assembly. The drive belt tensioner further includes an idler pulley configured to contact the drive belt. A position of the idler pulley is adjustable relative to the mounting bracket to enable adjustment of the tension in the drive belt.

A method of a fan system directing an air stream at a target can include receiving, with a controller, a first image from an image capture sensor and analyzing the first image from the image capture sensor to determine a first location of the target. The method can also include receiving a second image from the image capture sensor and analyzing the second image from the image capture sensor to determine a second location of the target. The method can also include comparing the first location of the target and the second location of the target and sending a signal to a first motor to rotate a housing about a first axis respective to a base to direct an air stream exiting an outlet of a channel at the target.

A device for heating a room (2) in a building by means of underfloor heating, the floor comprising pipe loops (4) for circulation of a hot medium, preferably water. The floor has a subfloor (1) and an upper floor (8) at a mutual distance, so that an air-filled chamber (16) is formed between them. In the outer wall (3) of the room there are inlet openings (7) for fresh air, which by means of negative pressure ventilation in the room (2) flows into the chamber (16), over the pipe loops (4) to heat up, and out through outlet openings (9) in the upper floor (8). The heat absorbed from the pipe loops (4) goes partly up through the upper floor (8), partly out into the room (2) as heated air. The pipe loops (4) extend transversely of the direction of movement of the air from the inlet (7) to the outlet (9) and are partly cast in concrete on the bottom of the chamber (16).

Provided is an air conditioning system that maintains a room pressure in a clean room at high accuracy while having a simple configuration. An air conditioning system includes: a fan filter unit including a supply air fan to supply air to a preparation room from a chamber including space above a ceiling of the preparation room; a fan filter unit including a supply air fan to supply the air to the preparation room from the chamber; and a fan filter unit including a return air fan to return the air from the preparation room through the chamber and to exhaust the air from the preparation room, and further includes: a pressure sensor provided in the preparation room; and a control unit to control a return air fan based on a value detected by the pressure sensor.

An air-conditioning system includes: an air conditioner including an outdoor unit and a plurality of indoor units each provided in a corresponding one of a plurality of indoor spaces and each including a first control unit; and a second control unit capable of communicating with the first control units. Each first control unit is capable of communicating with a countermeasure device if the countermeasure device is installed in correspondence with one of the indoor spaces where the first control unit is located. The second control unit has a first function of prohibiting operation of the air conditioner if a first condition where communication between the first control unit and the countermeasure device is not established in any of the indoor units is satisfied.

An indoor pollution prevention system includes a plurality of gas detection modules, one or more intelligent control-driving processing devices, one or more gas-exchange processing devices, and one or more indoor cleaning and filtration devices. The gas-exchange processing device includes one or more flow-guiding component and a cleaning and filtration assembly. The intelligent control-driving processing device controls the operation of the indoor cleaning and filtration device in real-time under a surveillance condition, therefore the air pollution source in the indoor space passes through the indoor cleaning and filtration device, allowing the air pollution source in the indoor space to be filtered and exchanged to become a clean air.

A ventilation fan includes a body unit, which has a fan disposed in a body case and a fan controller operable to control an air volume of the fan. The ventilation fan also includes a sensor module having an indoor environment detecting sensor and a module controller operable to control a detecting operation of the indoor environment detecting sensor. The body unit has a module mount on which the sensor module is mounted and another sensor module can be mounted in place of the sensor module. The module mount is connected to the fan controller. The module controller outputs detection information obtained based on a detection result of the indoor environment detecting sensor to the fan controller, which in turn controls the air volume of the fan based on the detection information inputted thereto.

A ventilation fan includes a body unit, which has a fan disposed in a body case and a fan controller operable to control an air volume of the fan. The ventilation fan also includes a sensor module having an indoor environment detecting sensor and a module controller operable to control a detecting operation of the indoor environment detecting sensor. The body unit has a module mount on which the sensor module is mounted and another sensor module can be mounted in place of the sensor module. The module mount is connected to the fan controller. The module controller outputs detection information obtained based on a detection result of the indoor environment detecting sensor to the fan controller, which in turn controls the air volume of the fan based on the detection information inputted thereto.

A power conversion apparatus includes a converter circuit converting AC voltage output from an AC power supply into DC voltage. The converter circuit includes unit converters. The power conversion apparatus includes a low current-oriented controller the unit converters to cause current corresponding to a single phase to flow through a current detector, and a high current-oriented controller controlling operation of the unit converters based on a result of comparison between a duty command and a carrier signal, where the duty command is generated based on detection values detected by the current detector and a voltage detector. When the detection value detected by the current detector is less than or equal to a first threshold, the low current-oriented controller is activated, and when the detection value detected by the current detector is greater than the first threshold, the high current-oriented controller is activated.

A power conversion apparatus includes a converter circuit converting AC voltage output from an AC power supply into DC voltage. The converter circuit includes unit converters. The power conversion apparatus includes a low current-oriented controller the unit converters to cause current corresponding to a single phase to flow through a current detector, and a high current-oriented controller controlling operation of the unit converters based on a result of comparison between a duty command and a carrier signal, where the duty command is generated based on detection values detected by the current detector and a voltage detector. When the detection value detected by the current detector is less than or equal to a first threshold, the low current-oriented controller is activated, and when the detection value detected by the current detector is greater than the first threshold, the high current-oriented controller is activated.