I have a contractor who didn't install a water heater to the manufacturer's specs and it is not functioning as designed to operate. This was confirmed with discussions with the manufacturer during phone conversations with them. The contractor damaged walls, no hot water, installed connecting gas lines, not per the agreement, and connecting hot/cold water lines to the correct inputs, punctured electrical lines in my wall from drilling holes. I told the contractor to remove the item out of my house, per his original offer to me. He never responded to my repeated attempts for him to pick it up. Consequently, He took the easy way out and filed a Mechanic's Lien against me. What recourse do I have to object this assertion, based on the true facts to this case?