called with caller id showing air duct cleaning.  Man was very rude and loud with me.  When I called the number back, immediately to make a complaint, The recording said the number was disconnected.

Called and said they previously did air duct work for us in the past and now time to do our furnace. We never used this unknown company. Called the number back and recording says this number not in service.

Said they did work for us and on their way to do a yearly check.  I told him I'd check with my husband.  Man was insistent that he come over and my husband could call to cancel and I said no.  He hung up on me.  Later, when I told my husband, we called the number back and it was not in service.  Pretty much the same as the other caller complaints.

this is a scam number that I can only assume is preying on the elderly who they think won't remember that AA Duct Cleaning was NEVER at their house. Have received at least 4 calls over the past 3 months but call backs result in it not being a working number.

This person called saying that they were some duct cleaning company and that it was time for my furnace to be checked.
He did know my home address, which I didn't like.  He also called my brother last week and insisted that he would be coming out to check his furnace.  The discussion got into an imaginative fisticuff of scenes, where if he did come out, he would get his @##@ whooped and vice versa.
The police were called.