I had been unhappy with another firm in Madison that has worked on both our furnace and central air conditioner, so I contacted Clark, based on a recommendation from Dan of Jenko's garage doors, and checking on Angie's list, where Clark was highly rated. They sent a serviceman (I think it was Kevin) last Tuesday, who inspected our system, which had been installed in 1992, and determined it was leaking Freon. He indicated that repair was not a smart option on an old system and recommended a new air conditioner. Andy came came out on Thursday to give us an estimate. I asked if he could have it installed on Friday, as it was very hot and humid and we were having guests over for dinner. He said he could make it work. On Friday his crew (Jeff and his partner) spent about 5 hours removing the old unit and installing the new one. They were completely professional and thorough. By 5:00 the house was cooling down. I highly recommend Clark Heating and Cooling.