Check to see whether any pipes are touching.
DIAGNOSIS 1
Step 1
Check whether any pipes are touching wall of compressor area.
Step 1
Check whether pipes are touching drain pipe or drain tray.
DIAGNOSIS 3
Step 1
Check whether tube is well-attached to water tray.
DIAGNOSIS 4
Step 1
Shake the tray to feel if it is loose.
Check whether pipe is resonating noisily.
DIAGNOSIS 6