My 20 year old outside unit was screeching this evening. This happened
once before a few weeks back. At that time it stopped on its own.
Tonight I eventually turned off the AC after a minute or so of the
noise. There is a slight mechanical burning smell at the unit itself.
There is nothing inside blocking and it is turning but entirely too
painful sounding to leave on.
Are there things to try before calling someone out?
Any help with be greatly appreciated.