JPH0373788B

• Main Authors: SAKAI TOSHUKI, YUZUTA JIRO
• Format: Patent
• Language: English
• Published: 22.11.1991
• Subjects: AIR-CONDITIONING, AIR-HUMIDIFICATION, VENTILATION, USE OF AIRCURRENTS FOR SCREENING; BLASTING; HEATING; LIGHTING; MECHANICAL ENGINEERING; RANGES; VENTILATING; WEAPONS

PURPOSE:To certainly change four-way valve, as well as to prevent frost in an air-conditioning machinery room, and to obtain comfortable humidity even in the time when air heating operation is stopped, by performing dehumidifying operation for a predetermined time after air heating operation is stopped, and by operating a variable-frequency compressor above the specified frequency range for a predetermined time at the beginning of dehumidifying operation. CONSTITUTION:When an air heating operation stopping signal is outputted from an air heating operation stopping signal generator 22, a pilot solenoid- operated valve 8 is deenergized at the same time the operation of a humidifier 21 is stopped. At this time, a compressor 1 is operated by a frequency controller 14 above the specified frequency range for a predetermined time. By this operation, a bypass for gas through the pilot solenoid-operated valve 8 is cut off, though the port 8B of a valve 8 is held in the open state. Accordingly, difference is produced in the pressure between the right and the left sides of a sliding part 9G, and the valve 8 is completely switched to the left side to start dehumidifying operation.