The house is right around two hundred years old, and when my husband and I purchased it, almost everything was extremely outdated. The house has not been well cared for, and we had to deal with rotting wood, crumbling plaster, and water damage. The plumbing was corroded and leaking. The electric lines were a fire hazard and there was only one power outlet for each room. Most of the windows were painted shut, and they all leaked a tremendous amount of air. One of the worst problems with the house was the HVAC system. The furnace and air conditioner were ancient and had never been professionally serviced. There was visible dust and debris clogging the air vents, the furnace was rusty and corroded, and the air conditioner showed signs of mold and bacteria. We were reluctant to run the furnace because of the potential for carbon monoxide poisoning. We were just as afraid of operating the air conditioner as it posed a threat to indoor air quality. Some of the water damage inside our home seemed to have been because of the cooling system. We hired a local HVAC contractor to inspect the furnace, air conditioner, and duct system and supply us with an estimate to fix the whole thing. We were hoping to avoid purchasing and installing a completely new HVAC system. Fortunately, the duct system can be salvaged with sealing and cleansing, but the air conditioner and central warm air furnace were beyond help. They were both so outdated and inefficient anyway. We saved money by upgrading to modern units designed to cost far less to use.