I have a split heat pump unit. The unit inside in the attic started making a loud whining sound. I'm guessing it has something to do with the blower motor. When it shuts off you can hear it whine down. Almost like a baseball card in tire spokes...but a high pitched whining sound.

It seems to be working ok but it is so loud it woke us up and I had to shut the system off.

Any ideas?