Can anyone help me out. I had a 3ton Janitrol sysytem installed in my 1875 sq ft home three yrs ago. This past summer something has happened to the A.C. It no longer cools the house down. I've had two different repair companies out to look at it, and both say the gauges indicate the system is operating correctly, it must be something with the house( ie, more insulation needed). If this is the case why did it cool efficently for two years? Any input would be appreciated.