Vent cleaning is a scam, and the services on Living Social/Groupon/etc are often a "loss leader" where they try to get you to upgrade. Be wary of carpet cleaning, vent cleaning, window cleaning, service calls etc from those groupon deal sites.

Rip off. Show him the door.

Vent cleanin as a whole is a scam.

My husband bought a professional vent cleaning to our newly purchased house through Living Social. Today they came (2 guys) and one of them asked to look at my basement. A few minutes later he came back to tell me he had found 2 problems - mold and that because my main line had never been cleaned, once they turned the system back on the vents would get dirt again because of the main line pushing dirty/dust to them.

I asked him to see the mold problem and he asked me if I wanted to see a pic instead to which I replied I rather he show it to me.

We go downstairs to the machine room and he goes on and on how it had a leak before and it was replaced (I knew it already from inspection) and then he took the filter out and pointed (with the flash light) to a TINY white dot (ONE) at the back of the filter case.

He then said again the same thing about the main line and said he could clean it for me and remediated my mold problem. I thanked him and said I only wanted the service we had already payed for through living social.

He got a little testy and said once again my vents would get dirt again.

Anyway, I just didn't get a good feeling about the whole thing and felt he was trying to scam me.

OTOH, is this "main line" a real thing? Should I really have it cleaned?