I am a Realtor and I have a customer that wants to make an offer on a foreclosed condo but there is a low-voltage wire running from the air-handler about 30 feet out along the wall and out the back door, then into the wall outside. I've never seen anything like it in 25 years on the job and I have no idea what it could be for. They made no attempt to snake it through the wall or even tuck it in the carpet. In fact, it is too short to even lay on the carpet. It just hangs there from the second floor down to the first and out the door! It can't be for the thermostate as it runs into a wall on the outside patio. Would anyone have any idea what it could be? I have pictures of it. Thank you very much.