Pollution degree determining method in air channel of air conditioning system, involves receiving acoustic signals generated at preset durations, based on difference in which pollution degree is estimated

摘要

An acoustic signal which is generated by a sound source at specific location of air channel system, is received by a microphone provided at a preset distance from the air channel system. Another acoustic signal generated after a certain duration is received by the microphone. The dust deposited in the air channel system, is detected based on the difference in the received signals.