hey guys...I got a year old Trane 14xl...if I recall correctly. I have heard it make the SSSSSSSHHHHHHhhhhhhhh noise now and then this winter...the one that seams to come from outside the house... but tonight and maybe a few times over the last few days I have heard it make a more violent noise with more of a rubbing noise....maybe like turning a rusty spicket off. I've heard it 3 times tonight. The temp outside is 36 degrees, humidity is 86% and its rainy. The weather has been of the type where it feels a little warmer than the degrees would have you believe.

Is this noise normal. Should I have the installers out to check it out? What could it be?