I just had a 3-ton Ducane system installed. My return vent is 32x16 and is located in the main hallway. When the system turns on there is a loud whistle coming from it. I went to remove the filter to see if it helped but when I lowered the grill the noise stopped. I tried rotating the grill but the whistle continues.
Another question: The system will be set for 73 and the inside temp is 73 however, the system will turn on and run for about 20 minutes and shutoff for 5 and then run again for 20 minutes. The inside temp will never go above 73 before the system turns on. Is this normal? Are the run times correct?
I live in New York and it was 95 today.
Thanks in advance for all your help.