Making The Exchange: What You Should Know About Heat Exchanger Damage

A cracked heat exchanger is a serious concern because it is a vital part of the furnace operation. If a recent furnace inspection revealed a crack in the heat exchanger, your HVAC service technician may recommend that you replace the exchanger. In some cases, though, it may be more cost-effective to replace the entire furnace. It's helpful to understand the basic function of the heat exchanger and the risks of the damage before you make a decision.

Exploring Basic Heat Exchanger Function

Heat exchangers are dual-chambered units that typically contain two different fluids – one in each chamber. The chambers are sealed and attached to a network of pipes that allow for circulation. The heat passes from the furnace to the first fluid, and then it transfers to the second fluid. The furnace cools as the first fluid absorbs the heat, and then the first fluid does the same when it passes the heat to the second chamber.

This creates a cooling cycle that helps to keep the furnace itself cool. The multiple stages of heat transfer help to make the cooling a progressive action so that you don't have a sharp contrast in temperatures that can damage the furnace structure.

Understanding What Causes Heat Exchanger Cracks

Every time your furnace runs, the heat exchanger runs, too. This means that your heat exchanger is regularly warming and cooling, which can cause the metal it's crafted from to expand and contract repeatedly. Over time, this cycle will strain the metal and make it brittle. This leads to cracks in the metal.

Once the metal is cracked, your home's heating ducts can be exposed to carbon monoxide. This is a serious health concern for you and your family. As a result of this hazard, most furnace technicians will recommend that you deal with a cracked heat exchanger right away when it's discovered.

Deciding How To Deal With The Damage

Before you make the decision to just replace the exchanger itself, you should take time to consider the condition of the furnace as a whole. If the furnace is nearing the end of its recommended lifespan, you should ask your HVAC technician about replacing the whole furnace instead. ENERGY STAR recommends that you replace your furnace if it is nearing fifteen years old.

You may think that investing in a new furnace simply to repair a damaged heat exchanger is unreasonable, but if your furnace is older, a new one may actually save you money over time. Newer furnaces are more efficient, and you might find that you can get the same heat production from your new furnace at a fraction of the fuel consumption.

If your furnace is less than fifteen to twenty years old, it may be more cost-effective to replace the heat exchanger. In fact, you may even find that the repair is covered under the warranty from the manufacturer. Talk with your HVAC technician about the warranty coverage that may still be applicable for your furnace, as it could save you significantly on the replacement. Otherwise, you'll want to have a new heat exchanger installed to restore your furnace to a safe operating condition.

Tips For Avoiding Heat Exchanger Issues

Routine furnace maintenance is the most important part of protecting your heat exchanger from damage. Reduced airflow in the system, poor combustion and other similar functional problems can increase the heat inside the furnace, which can increase the risk of damage to the exchanger.

Additionally, if you have any condensation forming inside the heat exchanger due to the temperature fluctuations, it may be rusting. This rust can weaken the metal encasing the exchanger. The best way to identify any of these issues is by having your furnace inspected and cleaned at least once or twice a year.

If you have any reason to be concerned about the condition of your furnace or its heat exchanger, an HVAC technician is the best place to start. He or she can evaluate the entire heating system to determine where your hazards are, if there are any. Then, you can decide whether to pay for repairs or a complete replacement.