Just over 2 years ago we bought a house with a dated A/C package unit.
14 months ago we replaced the A/C with a 3 ton Trane package. After
about 9 months of improved cooling over the old unit, we began to
experience problems with cooling, pipe leading from the condenser to
the coil froze, etc.

After several service calls to the installer (from whom we purchased
the unit), the diagnosis was there was a blockage in the return. I
subsequently removed the ceiling of a closet and a portion of an
interior wall in order to access the return duct work. End result =
no blockage. However, the return duct for some reason is sealed off
at the exterior wall. From the outside, the unit is tied into a
return duct that terminates 8" inside the wall.

This problem does not appear to be covered in the warranty, which is
the standard 1 year parts and labor, 5 year parts only. The invoice
for install reads only, "...remove existing package unit...install
(new) package unit on existing slab hooked to existing duct work..."

This may have been a pre-existing condition with the old unit. We
assumed the old unit limped along because of age. In any event, had
the new installer taken readings at the return and supplies 14 months
ago, much less peeked inside the duct from the outside, surely they
would have seen a problem. Instead, they dropped the unit on my slab,
taped it up, and ran to cash my check. Now 14 months later I have
spent hundreds in service calls, my ceiling and floor is ripped down,
and my return duct looks like swiss cheese.

In my opinion, they need to remedy the duct situation, refund the
service calls, and replace the unit. The logic being that due to
their negligence during the install, the current unit has undergone
considerable wear and tear working against itself for 14 months, and
is more likely to break down in the future.

I would appreciate any recommendations from anyone in the industry.