In a home we own in another state, we recently had a patio constructed. To do this they had to move the heat/AC unit away from the home. They physically cut all the lines and pulled the unit away from the home - instead of disconnecting them. When the patio was complete, they taped them back together. We just happened to visit the home at the time they reconnected the unit, and found the unit wasn't working. We had the contractor and heat/ac guys back out to look at it. They told us nothing was wrong, it may have been the rain the night before, and they added more tape. After we left, a neighbor contacted us and said our unit was running continuously - never shut off. I contacted the contractor. He went out with the original heat/AC guys, and they weren't sure what was wrong, but said it wasn't the unit outside - it had to be something inside. The contractor had another heat/ac company come out. They looked at the outside and inside, and said it was a factory defect on the air exchange inside the home. The contractor is adament it has nothing to do with the unit being moved. I am looking at a $1,500 repair bill - IF the part is under warranty - more if not. Can this just be coincidence as the contractor states - the heat/AC was working fine prior to the unit being moved? He states they've told him nothing they did outside would affect what is wrong inside. Are the two completely independent - the outside unit, and the air exchange inside? HELP... I need to now how to proceed and I am completely not mechanical, and I don't know anyone to ask.