The main problem that we had was the process of getting the service people to get their collective act together. Promises not being filled, promises not being fulfilled and overall lax of customer service manager. Working up the management chain to Emerson, we finally reached a person, who true to his work, finally had the replacement unit shipped. This is the 3rd unit we have had installed. Hopefully the last. My downgrade was for the overall experience, although the product leaves something to be desired. The Emerson person told me that the units should last for a minimum8 years. Let's hope the 3rd unit does just that.