Beware Just like what you see on the Dateline NBC! A missing battery from thermostat controller, it ended up spending $300 plus. Less than thirty days later, icing started building up outside pipe. They sent technician, he said there were leaks from the Air Handler. When I asked him to show me the leaks, he could not find one. Though he recommended to replace the whole unit; the reason is because the unit he said is 10-year old. I made a few calls for second opinion and I found George Brazil with free diagnostic. They sent their guy and checked everything, he said it's true the unit is 10-years old but still does its job. And asked him about the icing on the pipe outside. He said the fan for the Air Handler caught a rope and trapped...caused not to spin....Up 'till now the AC works....