These blowers use an electric fan mounted inside a vent that wraps around the outside of the firebox. I would contact the manufacturer of the fireplace. Tips For Greater Fireplace Efficiency Wood Burning Fireplace Inserts Wood Fireplace Wood Fireplace Inserts Click to see full answer. How to work a fireplace with a blower . How does a gas fireplace blower work? The fan draws cool air in from the bottom vents and heats it up inside before being forced out into the room at the top. The switch closes at 120°f (blower on) and opens at 90°f (blower off). Because the warm air is produced by an electric heater, there is no burning or emissions of any kind. How does a fireplace blower work? As the air travels around the hot fireplace, it heats up, and by the time it is released into the room, the air is much warmer than the rest of the room. How do fireplace insert blowers work? How does a fireplace blower work? A heating element, usually in the form of a heating coil, wa...