Sears Carrier Air Conditioner, 3.5 Ton Review

Purchased a Sears Carrier Whole house Air conditioning unit and had the installation from hell.  The contractor did not even install all the parts and took months to finish.  Knew there was a need for a cross over under the house and wouldn't tell us, says  he would lose his Sears Contract if he did.  I tried to tell him that air wasn't coming clear thru to the back of the house, and he had the nerve to tell me it would adjust it's self, just shut off part of the vents and it would be fine.  Finally got him to come up here, and it cost us an extra $300.00 to fix the problem that he wouldn't tell us about.  Unit will not cool the house if the temperature is over 100 degrees.  Set it on 80 degrees and it will run for hours, and can get it down to 81 degrees part of the time.  Have had a couple of people (other a/c repair companies) inspect the unit, they say it runs fine, sloppy installation, but works ok, but is too small for the  house due to the large arcadia doors, large windows, and three big skylights.  The man who sold the unit did not take any of that into consideration, and now our bills are high because it runs constantly, and Sears won't do a thing about it.  So far I have talked to a manager, an area manager (who promised a month ago to come up and check the house) and a manager for the region(AZ, and California)  So far no one has shown up, nor called to get the problem fixed.  Sears has a customer motto that says customer satisfaction.  I guess that only applies to small appliances, not something that costs thousands of dollars.  We asked for a 4 ton unit, and the sales person said we didn't need it and had put in what he felt we needed.  I feel that Sears should fix the problem and make the unit a 4 ton so it will cool the house adequately.  DO NOT BUY FROM SEARS  if you need an air conditioner for your home. Buy from a LOCAL independent contractor who lives and works in the area, and you can check his references and work. We requested that they have a LOCAL contractor do the installation and instead sent someone who was 4 hours away(one way)  Was almost impossible to get the contractor to return to make anything right.  We have Sears contractors close (1 hour away) that could have done the job.  Since we live in Arizona, Air conditioning that works right is important.  If I could get them to pull the unit and refund our money, I would buy locally, but since I can't even get them to return calls, I am sure that will not happen either.