Wall Furnace Basics

• A wall furnace is a type of gas or electric furnace designed to heat a single room. Most home furnaces are attached to ducts that pull cool air out of the house and carry warm air in. The wall furnace differs from these primarily in that has no ducts, and pulls cool air out and pushes warm air directly into the room.
  
  

How Gas Wall Furnaces Work

• Wall furnaces have a single blower fan that pulls air in through one vent, past the heating system and out through a second vent. In some furnaces systems, the air is pulled into a vent at the top of the unit and out through the bottom, in others the air circulates in the opposite direction. In a gas wall furnace, the air is heated by a heat exchanger. Hot gas from the burners flows in tubes past the supply air, which gathers heat from the gas. The burnt gas is then vented through a small chimney to the outside.
  
  

How Electric Wall Furnaces Work

• In electric wall furnaces, the air is blown directly onto electric coils. The coils are resistors--materials that resist the flow of electricity. When an electric current is run through them, they become very hot, warming the air. Electric wall furnaces have both advantages and disadvantages compared to gas ones. They tend to be more expensive to run, but they are much easier to install, since they do not require a chimney or a gas line.