Asbuilt Comfort Care

Have had to have heat exchange replaced twice. First time was in 2005, Asbuilt did repair work, although it was under warranty labour cost 1200. Exchange went a second time was in 2012. Called Asbuilt who tried to charge me for diagnostic although the tech did not have tools to complete tests. (Have given 1 star as manager reversed the charge when I called to complain). Called Carrier and found out that the heat exchange was still under warranty but Asbuilt wanted to charge me for repair again. Carrier recommended another company .Technician was extremely knowledgeable and gave fantastic customer service. He said that ongoing problems were due to furnace not being installed correctly in beginning, (should have been sloped and was not) moisture was collecting, water was causing corrosion in the heat exchange. Asbuilt should have caught and corrected this in 2005! New company corrected problem and although this require much more time than anticipated, charged less then half of what Asbuilt initially quoted.