I had a leak that was coming down through my AC vent from upstairs. It was a freaky thing that was happening due to the freeze and thaw we had for a while. He was able to figure out that condensation was forming due to the conditions and causing the drip. He said it wasn't likely to happen again, but if it did I could call back and he would investigate it further. It hasn't come back again, though, so there's been no need. He was a very nice person. I'm a long time customer with them and their prices are a little steep, but the personable folks who come out keep me working with them. They're always very polite, they know their jobs and they arrive on time.