Yesterday I noticed there seemed to be no air coming out of the air ducts in my house. I have a Trane 2 1/2 Ton Model WCH30A100AA (self-contained outside unit), which was installed in April, 1988. My initial thought was that the blower motor was not working, as that seems to happen about every 4 years or so. I called the Technician who came out and determined, there was ice forming on the inside coils. The blower seemed to be working but the ice wouldn't let the air back into the house. He told me the unit was low on freon and added 1 1/2 pounds. Pressure was increased from 68/150 to 75/173. He also indicated the probable place of freon leak was at the the Schraeder Cap, which had a slight discoloration on either side. After letting the ice thaw , he added the Freon, and cool air started blowing. The air now coming out of the vents is 64 degrees, the air going into the return vent is 81 degrees, a difference of 17 degrees. It seems to be comfortable now. However, I have a some questions. Is his explanation a reasonable one? And, is the air in/air out ratio reasonable?
I realize the unit is getting fairly old, however, I don't want to replace it until it is necessary. Any suggestions will be appreciated. Thanks.