Mathew was very helpful in explaining the issue with our old thermostat and helped us chose the right replacement. The thermostat arrived right on schedule and when I went to install it the old one was working again. As a result I just spoke with Elmer and he said that I could return the unopened box for a full credit. But he also asked how old the existing until was which is about seven years and he said that is about the life expectancy and that the old one may fail again soon. On that basis I decided to keep the new unit. The bottom line is that I find this company to be very accommodating with a knowledgeable and very helpful professional staff. It is a good company to do business with.