Whether you have a furnace, an air conditioner, or a combined HVAC system, the unit in your home has a heat exchanger. The heat exchanger is a critical component that the unit can’t do without. So if it fails, your home will not get as warm or cool as would otherwise be expected.
Are you familiar with the heat exchanger and the science behind it? If not, it couldn’t hurt to learn the basics. You will certainly want to know what the heat exchanger does should an HVAC repair technician someday tell you that yours needs to be replaced.
Transferring Thermal Energy
The experts at Beehive Plumbing, a Utah plumbing and HVAC contractor in the West Haven and Sandy areas, describe the heat exchanger as a device that facilitates thermal energy transfer. The energy can be transferred between air and water, air and combustion gases, or air and refrigerant.
Due to the way heat is transferred, the heat exchanger can be leveraged to both heat and cool spaces. Your furnace relies on a heat exchanger to bring heat into your home. The air conditioner relies on the unit to remove heat from the home. Thermal transfer works in both directions.
Heating Your Home
In a heating scenario, the heat exchanger in the furnace receives heat from some external source. It could be gas, oil, electricity, or even thermal energy from the ground. Air is circulated across the heat exchanger with the blower system. It picks up heat as it goes and distributes it through the home via ductwork.
By setting things up this way, a furnace is able to heat the home without allowing warm air and combustion gases to mix. This is important if you have a gas or oil furnace. Blowing air across a gas or oil burner would push toxic gas throughout the home. By using a heat exchanger instead, this problem is avoided.
Cooling Your Home
The heat exchanger in an air conditioner is called an evaporator coil. It is filled with a liquid refrigerant that absorbs heat from the indoor air. As the heated refrigerant moves outside, it reaches a condenser coil and releases the heat. Then it circulates back into the house and repeats the process.
For the record, a heat pump works the same way – just in reverse. The evaporator coil is outside the home. It extracts heat from the ground or air before transferring it indoors to the condenser coil. Once in the coil, the refrigerant releases its heat.
Efficient Heating and Cooling
Before modern furnaces, air conditioners, and HVAC units, people used to heat their homes with fireplaces and fuel-burning stoves. There was no way to cool other than fans. Neither heating nor cooling was very efficient in those days. But the invention of the heat exchanger changed everything.
The heat exchanger is an efficient and mechanically simple way to promote thermal transfer. Because it exists, we have central heat and air in both residential and commercial buildings. We are all more comfortable because someone figured out the heat exchange principle.
When a Heat Exchanger Fails
When a heat exchanger fails, it is not absorbing enough heat from whatever source is available to it. Most failures require complete replacement. Fortunately, the repair itself is pretty straightforward.
Now you know what a heat exchanger is, what it does, and why you should care. If your home is not heating or cooling as effectively as it should, the heat exchanger could be giving you trouble. Call in a professional for diagnosis and repair.
