WF Smith installed our old unit of the same make and model number about 15 years ago. I only needed service once in all that time ( thermostat ) so I was very happy along with great performance and super quiet operation. When I needed a new unit, the choice was obvious. Dave actually called me back a couple of times when I left a message regarding an install date. The unit was installed on time with no issues. I regard WF Smith as a first class professional operation.