What Is A Heat Exchanger?

The Basics of a HVAC Heat Exchanger

A heat exchanger facilitates the transfer of heat from the combustible gases in your furnace to the cold air in a home. The furnace will generate heat by combusting gases in a closed chamber. These gases flow into the heat exchanger where they release heat to the cold air from your home or office space. For the heat exchanger to work efficiently, it should have an air-tight seal. Here is what you need to know about a heat exchanger. 

How Does a Heat Exchanger Work?

A heat exchanger is responsible for transferring heat from the furnace to the cold air in your home. Furnaces create heat by combusting gases in an air-tight chamber. These gases flow into the heat exchanger chamber where they heat the metal walls of the heat exchanger. As that happens, the return air ducts bring in cold air from the room, which flows over the outside of the heat exchanger. 

The cold air warms as it flows over the outside of the heat exchanger and flows back through the ducts to the rooms in a home. Combustion gases then flow through a vent and are released from the home. 

What To Do When a Heat Exchanger Breaks

Heat exchangers will break at some point. As they expand and contract, the metal parts will break and develop cracks. Cracked heat exchangers are a serious threat to the inhabitants of a home and should be replaced immediately. In an exchanger, the gases being burned include sulfur dioxide, carbon monoxide, and nitrous oxide. If they leak, these gases can cause an illness or lead to death in severe cases. 

You can tell the furnace heat exchanger has a crack if you see any of the following signs:

• Unpleasant smells from the exchanger

• Soot buildup in the exchanger and furnace

• Visible signs of corrosion and cracks on components of the furnace

• Change in color of furnace flame from blue to yellow or orange

• Audible sounds from the furnace 

• Presence of detectable carbon monoxide in your indoor air

When the heat exchanger breaks, you can have a technician replace the exchanger, replace the broken exchanger cell, or replace the entire furnace. Note that, other components of the furnace may be in need of replacement. 

Conclusion: The Importance of Heat Exchangers in HVAC Systems

An operational heat exchanger ensures that your home is always as warm during cold days and there are no harmful gases in the air. If you see any of the signs above, call a furnace technician immediately for a remedy.