Sullivan Super Service was terrific this last time as usual. We've used them for at least the last 10 years and the work that they have done includes getting the furnace replaced, water heater, air condition unit and probably a few other things for the house that we purchased 20 years ago.
They have always been very courteous to us, they call us within 10 min after you ask them to and even though they are not cheap, they do quality work that doesn't fall apart after a few months. They are highly recommend them by me and my wife.