Moderator Post (s) for this thread: >Choice propertybyHKestenholz on 01/25/2008
You are at an interesting decision making point you got a long and fruitful life out of your previous system but the extra energy you paid for in the last ten years would have paid for a new unit.
The good news is that in the last ten years technology has evolved to help you out even more.
To properly evaluate this decision from a financial stadpoint you need to get your gas utility provider to tell you what they will charge to provide gas service to your house it should not be much if anything especially if the gas main is less than 200 feet from your house.
My recommendation is to install a duel fuel or what I call a hybrid system you already have electrical capacity available as you already had a heat pump the only unknown is the cost of gas service.
Here is how it works you will have a heat pump minimum 13 seer all year long until it gets really cold outside then instead of electric auxiliary heat you would have a gas furnace as your auxiliary heat taking advantage of the time when a heat pump is very efficient(60 to 40 degrees) then the gas furnace takes over at colder temperatures, let me know what you decide, thanks