First off, you can’t expect something as complex as a furnace to last forever. Says Tim David, owner of Airlucent, an HVAC ...

If you need to purchase a gas-burning forced-air furnace but aren't sure how they work, here's what you need to know.

Skipping the manufacturer's instructions during installation may result in a furnace that fails within six months or less. For example, heat exchangers can crack from improper venting, and gas valves ...