Abstract: A safety system (1) for evacuation of contaminated air and prevention of ignition in an air handling system (2). The air handling system (2) comprises a compressor enclosure (3). The safety system (1) is connectable to a power supply (4) and comprises an evacuation unit (5) connected to the compressor enclosure (3) for evacuation of contaminated air from the compressor enclosure (3).

Abstract: Method and device for reducing or eliminating a temperature drop of the supply air temperature during defrost operation, at an air handling unit (1) which is arranged with a heat pump (2) for recovering heat from an extract air stream (3) and transfer to a supply air stream (4). During defrosting of a first DX-coil (5), arranged in the extract air stream (3), by reversible operation of the heat pump (2), accumulated heat energy (E) is used for reduction or elimination of the temperature drop in the supply air temperature during the defrost operation, and which energy has been stored in an accumulator medium (7) which is at least partially in contact with the supply air flow (4). The stored energy (E) is delivered by heat exchange with the supply air stream (4) in a position after a second DX-coil (6) through a heating coil (8) arranged in the supply air stream (4).

Abstract: An apparatus for measuring air flow in a duct includes a sensor fittable into connection with the duct. The sensor includes an ultrasound transmitter, at least two ultrasound receivers, and a control unit to which the ultrasound transmitter and ultrasound receivers are connectable. The apparatus further includes means for measuring temperature. In a method, with the apparatus, the temperature of the air and/or of a sensor in a duct is measured with means for measuring temperature. A sensor calibration measurement at the temperature in question is performed with the apparatus if a calibration of the sensor at the measured temperature and/or within a certain predefined temperature range has not been performed earlier from the environs of the measured temperature, and temperature compensation data for the measurement result of air flow, the data being formed on the basis of calibration measurement, is determined and/or recorded in memory with the apparatus.

Abstract: A comfort cassette (1) and a method which comprises a pressure box (2) with an inlet (3) and a plurality of outlets (4) for through flow of a supply air flow (L1). The outlets (4) are arranged at more than two of the pressure box edges (5a, 5b, . . . 5n) and form a group (6a, 6b, . . . 6n) of outlets per edge (5a, 5b, . . . 5n). The outlets are arranged in a configuration which is changeable by outlets (4) of a cover member (8) when the cover member (8) is displaced in relation to the outlets (4) of the pressure box (4). The cover member (8) is arranged to change simultaneously the configuration of all groups (6a, 6b, . . . 6n) of the outlets, by movement of the cover member (8) in only one direction, while the supply air flow (L1) is changeable in more than two directions by movement of the cover member.

Abstract: A safety system (1) for evacuation of contaminated air and prevention of ignition in an air handling system (2). The air handling system (2) comprises a compressor enclosure (3). The safety system (1) is connectable to a power supply (4) and comprises an evacuation unit (5) connected to the compressor enclosure (3) for evacuation of contaminated air from the compressor enclosure (3).

Abstract: In an apparatus and method for measuring air flow in a duct, e.g. in a ventilation duct, the apparatus includes a sensor fittable into connection with the duct at a certain distance from an interference source, the sensor including an ultrasound transmitter and at least two ultrasound receivers, and a control unit to which the ultrasound transmitter and ultrasound receivers are connectable. The control unit is adapted to measure the phase difference of the ultrasound signal received at the same moment in time by at least two ultrasound receivers fitted into connection with the duct and, based on the measured phase difference, to determine the flow velocity and/or flow direction of the air. The control unit is adapted to compensate the determined flow velocity and/or flow direction of the air with a coefficient that is formed on the basis of the diameter of the duct, the type of interference source and the distance between the sensor and the interference source.

Abstract: An apparatus for measuring air flow in a duct includes a sensor fittable into connection with the duct. The sensor includes an ultrasound transmitter, at least two ultrasound receivers, and a control unit to which the ultrasound transmitter and ultrasound receivers are connectable. The apparatus further includes means for measuring temperature. In a method, with the apparatus, the temperature of the air and/or of a sensor in a duct is measured with means for measuring temperature. A sensor calibration measurement at the temperature in question is performed with the apparatus if a calibration of the sensor at the measured temperature and/or within a certain predefined temperature range has not been performed earlier from the environs of the measured temperature, and temperature compensation data for the measurement result of air flow, the data being formed on the basis of calibration measurement, is determined and/or recorded in memory with the apparatus.

Abstract: An air treatment device (1) and a method for heating of aft, in a heating mode, at an air handling unit (2), which comprises a heat recovery device (3). The device further comprises a heat pump (6), comprising an evaporator (7), arranged in a first air stream (4), in the flow direction, after the heat recovery device (3), and a condenser (8) arranged in a second air stream (5), in the flow direction, after the heat recovery device (3). The device further comprises an auxiliary heater (9) for supplying, in addition to the recovered energy, external heat energy. The auxiliary heater (9) is positioned in the first air stream (4), in the flow direction, after the heat recovery device (3) and before the evaporator (7) for heating and thereby the heat pump (6) operation is maintained and a better total efficiency for the plant is achieved.

Abstract: In an apparatus and method for measuring air flow in a duct, e.g. in a ventilation duct, the apparatus includes a sensor fittable into connection with the duct at a certain distance from an interference source, the sensor including an ultrasound transmitter and at least two ultrasound receivers, and a control unit to which the ultrasound transmitter and ultrasound receivers are connectable. The control unit is adapted to measure the phase difference of the ultrasound signal received at the same moment in time by at least two ultrasound receivers fitted into connection with the duct and, based on the measured phase difference, to determine the flow velocity and/or flow direction of the air. The control unit is adapted to compensate the determined flow velocity and/or flow direction of the air with a coefficient that is formed on the basis of the diameter of the duct, the type of interference source and the distance between the sensor and the interference source.

Abstract: An apparatus and method for measuring air flow in a duct, e.g. in a ventilation duct, includes a sensor fittable into connection with the duct, the sensor including an ultrasound transmitter and at least two ultrasound receivers, and a control unit to which the ultrasound transmitter and ultrasound receivers are connectable. The control unit is adapted to measure, during the measuring of air flow, the phase difference of an ultrasound signal received at the same moment in time by at least two ultrasound receivers fitted into connection with the duct and, based on the measured phase difference, to determine the flow velocity and/or flow direction of the air. The apparatus is adapted to perform a calibration of the apparatus by transmitting with an ultrasound transmitter at least one calibration signal and by receiving the calibration signal with at least two ultrasound receivers.