Most fans are wired into the fireplace with a fan sensor switch. This switch will activate the blower when the firebox heats up to a certain temperature. It will also automatically turn the blower off when the fireplace is turned off and the unit cools to a certain temperature. This sensor is provided so that you will not be circulating cold air in your home. The amount of time needed to heat up the fan sensor will differ depending on the model of your fireplace. It is common that blowers installed in Firebrick products will take longer to sense the heat and turn on your blower. Firebrick has greater insulating characteristics and holds the heat inside your firebox resulting in higher radiant heat and greater efficiencies
