In the solution put forth, there is a frame structure (122) and an inner surface structure (124) in an installation frame (110) of an exhaust blower (108) of a building (100). A bottom part (130) of the frame structure is intended to be installed towards a lead-through (106) of the building, and a top part (132) towards the exhaust blower installed over it. The frame structure surrounds the inner surface structure so that it does not cover bottom and top parts (126, 128) of the inner surface structure. The inner surface structure forms a suction channel (134) allowing exhaust air (114) flow through the frame. Inside the installation frame, a controller (112) has been installed, adapted to measure the exhaust air flowing in the suction channel and to generate, on the basis of the measurement, a control command for the exhaust blower to control the operation of the exhaust blower.

In the solution put forth, there is a frame structure (122) and an inner surface structure (124) in an installation frame (110) of an exhaust blower (108) of a building (100). A bottom part (130) of the frame structure is intended to be installed towards a lead-through (106) of the building, and a top part (132) towards the exhaust blower installed over it. The frame structure surrounds the inner surface structure so that it does not cover bottom and top parts (126, 128) of the inner surface structure. The inner surface structure forms a suction channel (134) allowing exhaust air (114) flow through the frame. Inside the installation frame, a controller (112) has been installed, adapted to measure the exhaust air flowing in the suction channel and to generate, on the basis of the measurement, a control command for the exhaust blower to control the operation of the exhaust blower.

A heating, ventilation, and air-conditioning (“HVAC”) system. The HVAC system may include a refrigeration circuit and a blower system. The refrigeration circuit may include a compressor, an outdoor heat exchanger, an expansion device, and an indoor heat exchanger. The blower system may include a first direct-drive blower and a second direct-drive blower. The first direct-drive blower may flow air over the indoor heat exchanger. The second direct-drive blower may flow air over the indoor heat exchanger and the second direct-drive blower may operable and positionable relative to the indoor heat exchanger independently from the first direct-drive blower.

A heating, ventilation, and air-conditioning (“HVAC”) system. The HVAC system may include a refrigeration circuit and a blower system. The refrigeration circuit may include a compressor, an outdoor heat exchanger, an expansion device, and an indoor heat exchanger. The blower system may include a first direct-drive blower and a second direct-drive blower. The first direct-drive blower may flow air over the indoor heat exchanger. The second direct-drive blower may flow air over the indoor heat exchanger and the second direct-drive blower may operable and positionable relative to the indoor heat exchanger independently from the first direct-drive blower.

An air treatment device includes a casing with an air inlet and an air outlet. Air flows through the casing and an air treatment section in the casing. The air treatment section includes a fan for generating a flow of air from the air inlet to the air outlet, a filtering means arranged within the flow of air, a first pressure sensor to measure a first pressure in the flow of air, a second pressure sensor to measure a second pressure in a room or cabin surrounding the air treatment device, and a control unit. The control unit is configured to adapt a speed of the fan based on the measured first pressure and the measured second pressure to control a flow of air through the air treatment device.

Methods and systems described perform air cleaning and/or sanitization in a heating, ventilation, air conditioning, and/or refrigeration (HVACR) system by detecting a concentration of airborne contaminants in a space serviced by the HVACR system. The detected concentration of airborne contaminants is determined whether it exceeds a threshold relative to a capacity of a first air cleaner. When the detected concentration of airborne contaminants exceeds the threshold, a second air cleaner is selected and enabled to be activated in the space. When the detected concentration of airborne contaminants does not exceed the threshold, the first air cleaner is selected and enabled to be activated in the space. The first air cleaner has a cleaning material different from the second air cleaner, and the first air cleaner, relative to the second air cleaner, treats the space at a lower concentration of airborne contaminants. The second air cleaner includes specifically designed cleaner modules.

An air-conditioning apparatus having a refrigerant circuit, in which a compressor, an outdoor heat exchanger, an expansion device, and an indoor heat exchanger are connected by a pipe and refrigerant circulates in the pipe, includes an indoor fan configured to supply an indoor air to the indoor heat exchanger, and a controller configured to control the compressor and the indoor fan. The controller is configured to run the compressor at a start of a cooling operation, start running the indoor fan at less than a set minimum wind velocity after a first set time has elapsed since the compressor started operating, run the indoor fan at the set minimum wind velocity after a second set time has elapsed since the indoor fan started operating at less than the set minimum wind velocity, and run the indoor fan at a set wind velocity after a third set time has elapsed since the indoor fan started operating at the set minimum wind velocity.

An air conditioner at least including a controller, a first fan unit, and a second fan unit arranged parallel to the first fan unit is disclosed. The controller performs a parallel operating control procedure, including a first control mode and a second control mode, to the first fan unit and the second fan unit respectively. When operating under the first control mode, the controller adjusts the rotating speed of one of the first fan unit and the second fan unit based on a first standard air volume, so the two fan units output the air volume equal to or approximate to the first standard air volume. When operating under the second control mode, the controller controls the rotating speed of both the first and second fan units according to a second standard air volume, so the two fan units output the same air volume.

An air filter and a method of air filtration using the air filter are described. The air filter may comprise a filter media adapted to capture and filter one or more impurities from air. Further, one or more sound wave generators are attached at one or more sides of the filter media. The one or more sound wave generators generate acoustic waves to be propagated into the filter media. The air filter may further comprise a plurality of sensors positioned before the filter media and after the filter media. Further at least one fan is positioned before or after the filter media. Further an IoT is configured to control frequency of the acoustic waves generated by the one or more sound waves generators, and interconnected with power signal control panel parallel, AHU to control rotational speed of the at least one fan based on value provided by the plurality of sensors.

An air filter and a method of air filtration using the air filter are described. The air filter may comprise a filter media adapted to capture and filter one or more impurities from air. Further, one or more sound wave generators are attached at one or more sides of the filter media. The one or more sound wave generators generate acoustic waves to be propagated into the filter media. The air filter may further comprise a plurality of sensors positioned before the filter media and after the filter media. Further at least one fan is positioned before or after the filter media. Further an IoT is configured to control frequency of the acoustic waves generated by the one or more sound waves generators, and interconnected with power signal control panel parallel, AHU to control rotational speed of the at least one fan based on value provided by the plurality of sensors.