Hello everyone...This is my first post and I don't know a thing about home repair so I was hoping that someone out there might be able to answer my questions. About 3 years ago we moved into our first home...a 1961 Colonial Style...it still had the original furnace and the hot water heater was about 10 years old. We deceided to have everything replaced and added central air. When they did this they ran the vent for the hot water heater right into the vent for the furnace. My father just came up to visit and claims that they should not have run the vent from the gas hot water heater into the vent for the gas furnace. However, my husband says that they would not have done it that way if it was a problem. So, my question is should I call the contractor and have them come out and seperate the pipes that are connected? Is there really a problem (I mean the exahust is going outside even if the pipes are connected, right?)? Any help or information on this subject would be greatly appreciated. Thanks in advance!