| 摘要 |
PURPOSE:To secure the rate of air, passing through a heat exchanging unit, by a method wherein another suction port is opened when the increase of the ventilating resistance of a normal suction port has been detected, upon the operation of an air-conditioning machine, mounting an air filter having a high dust-proofing efficiency. CONSTITUTION:An air-conditioning machine is operated usually while sucking air from a suction port 5a. When an air filter 6, a charged filter 8 or the like is clogged and the ventilating resistance thereof is increased, the temperature rise of a heat exchanger 3 is detected by a temperature sensor 10, provided in the heat exchanger 3. When the ventilating resistance is increased and the rate of air passing through the heat exchanger 3 is decreased, the temperature of the heat exchanger 3 rises in the case of heating operation while the temperature of the heat exchanger 3 falls in the case of cooling operation. Then, the change of the temperature is detected by the sensor 10 and is compared with a reference value to command the operation of a means for opening another suction port 5c from a control unit. According to this operation, a motor 9 is driven to open a shutter 5d and suck air through the suction port 50 whereby the performance of the air-conditioning machine may be secured. |
