In gas furnaces, heat exchangers perform the vital function of ensuring effective heating and, moreover, household safety. The burner in your furnace doesn’t directly heat the air that flows out of heating vents throughout the house. Instead, the burner flame in the combustion chamber is separated from the system airflow by the heat exchanger. The burner heats the heat exchanger. In turn, that heat is transferred to air moving through passageways within the exchanger.
The Critical Component
Heat exchangers keep the burner flame and dangerous gases that are a natural byproduct of combustion — including deadly carbon monoxide — safely separated from the airflow that flows through your home. However, over years of service, repeated expansion and contraction as this metal component heats and cools may eventually cause a crack or other defect. Rust and corrosion may also affect the integrity of the heat exchanger.
A compromised heat exchanger is a safety hazard as it may allow odorless carbon monoxide gas to silently infiltrate the furnace airflow. For that reason, many local codes require an HVAC technician to “red tag” a furnace with a defective exchanger for the safety of the home’s occupants. That means the unit is shut down and made inoperable until it can be repaired or replaced.
Stay Safe — and Warm
The best protection against a defective heat exchanger is to schedule an annual furnace checkup with a qualified HVAC service provider. This comprehensive inspection and multi-point preventive maintenance procedure includes a visual check of the heat exchanger for cracks or other defects, as well as testing the system airflow to detect presence of carbon monoxide gas.
Defective heat exchangers are typically expensive to replace. If your furnace has passed the mid-point of its normal expected service life — most gas furnaces last 15 years or so — the expense of replacing the heat exchanger alone is often not worth it. In such cases, upgrading the existing furnace for a newer (and also more efficient) unit is the preferred option.
For important information about furnace heat exchangers, and to schedule an annual furnace tuneup and inspection, contact the heating pros at CCAC.
Our goal is to help educate our customers in Corpus Christi, Texas about energy and home comfort issues (specific to HVAC systems). For more information about HVAC topics, download our free Home Comfort Guide or call us at 361-678-2495.
Credit/Copyright Attribution: “1264187/Pixabay”