When does a gas furnace reach the point where it no longer needs repairs, but instead needs to be replaced? One of the major signs that a furnace has come to the end of its service is a cracked heat exchanger—which is a serious safety issue.Installing a new gas furnace requires technicians with the best training and experience so the new unit operates correctly and without safety issues. Contact Black Hills, Inc. Heating & Air Conditioning when you’re ready for a new furnace installation instead of more heating repairs.Furnace age and the cracked heat exchangerTo understand why a cracked heat exchanger often means it time to replace out the old furnace, your first need to understand why a cracked exchanger is a major problem. The heat exchanger is a clam-shell shaped metal chamber above the burner; it collects the high-temperature combustion gas from the burner and transfers the heat to its walls. When the blower sends air across the heat exchanger, the heated walls transfer their heat to the air. The exhaust vapor of the exchanger then goes safely out the furnace flue.If the exchanger cracks—even a small crack—combustion exhaust will escape through the crack as the exchanger expands during heating up. This exhaust is dangerous carbon monoxide, which is not only toxic to breathe but is highly combustible.Heat exchangers usually crack because of corrosion across their surface. Although it is possible for a younger furnace to develop corrosion along the heat exchanger walls, more often this is a sign of extreme age in the furnace. The long exposure of the metal and combustion gas can cause a chemical reaction that causes corrosion. If your heater is near, on, or past its manufacturer’s estimate lifespan, a cracked exchanger is an important sign that you need to have the heat replaced. Shut down the gas to the furnace and call a technician to schedule an inspection.Do not delay when it comes to the heat exchangerWe must stress that a cracked heat exchanger is potentially dangerous. With a younger furnace, you need to call for immediate repairs to replace the cracked exchanger. With older furnaces, you need to move on the replacement heater right away. We recommend you have carbon monoxide detectors in your home to warn you of a rise in gas levels. Also pay attention to the appearance of corrosion on the outside of your furnace, or strange clicking sounds from inside the cabinet before the blower fan comes on. These are often warnings that there is trouble with the heat exchanger.Call Black Hills, Inc. Heating & Air Conditioning to schedule installation for a new furnace. We can help pick the new unit and size it so you’ll have years of safe warmth.