New Carrier AC Rooftop heating and cooling unit installed on our house in 2008. End of 2010 cooling season unit stopped working, found 3 pounds, (out of 9 pounds total), low on refrigerant. Leak is located in the Evaporator Coil. This is a "packeged" unit and comes from the factory tested and ready to run. The HVAC Service-Technician states that it is a slow leak, and will last thru this cooling season. It ran for 3 summers with no problems. Carrier Corp will replace the evaporator coil free, it is still in warranty, but the labor is $750. I believe Carrier Corp should pay for the labor. read full review »