If your Phoenix-area home was built without a furnace, it probably has no ductwork. Ductwork is essential for central air conditioning and most heat pumps. Ductless systems can be added to your home, but for the full force and cool comfort of air conditioning, [...]
An old furnace can be very expensive. Keeping a gas furnace in your home – when new, high-efficiency gas models are available – can cost you thousands in unnecessary fuel costs, repair work, and annual upkeep.
High-Efficiency versus Standard Models
Gas furnaces today are far superior in wise use [...]