We have had our A/C system since September of 2009. This is our 8th full year and although we have had some problems with the Lennox A/C that we purchased (parts on the system seem to break very easily) the technicians have always arrived promptly, were professional, and fixed all problems very quickly. As an aside I don't know if I would buy Lennox again. This is my second Lennox (the first was installed by another company) and it seems to be extremely fragile. My mother has a Rheem system that was installed in 2005 and not one part has gone on that yet and my place of employment has a York system since 2009 and nothing has broken on that.