Be careful changing your thermostat. My husband instisted I change (hes cute not handy) ours when we moved in because he is MODERN (so he thinks) and just had to have the digital theromostat instead of the "OLD" slide temp thingy. Well his 60 dollar generic brand from lowes thermostat ended up costing us 400.00 in service call and 120.00 for a new thermostat that is made for our system. We left one day and came home to the fan not working on our system (during the hottest part of the summer it was over 100 degrees in the house) it had pretty much ran itself to death because after three months the thermostat and unit decided they no longer wanted to be in a relationship! We have a Trane system and you have to have a "special" compatiable thermostat for them!