Hello. I recently had to have my gas furnace replaced. I went through the home warranty so a random company was sent out to do it. They finished yesterday and I was less than pleased with what I saw. First there was water coming down the flue pipe as it was raining, he told me not to worry as it would seal itself. My first question is, is it even possible for something to seal itself. Secondly he had zip tied some of the pipes together. Is that normal? Lastly, is it normal for a smaller metal pipe to be put into a larger pvc pipe? ive tried to add photos to help. Any help would be appreciated, I'm trying to stay away from paying more money to have someone else come look at it.