Cracked Heat Exchanger – Why It Happens and How to Prevent It
Cracked heat exchangers aren’t always as obvious as in the picture above. They can often be hidden or much smaller than this, but any crack should be treated of equal concern to the health of you and your family.
A heat exchanger is used to exchange heat between two different liquids and/or gases. It is meant to allow your HVAC system to run more efficiently using by-products of the system’s operations to act as a coolant or heater, depending on the system.
Problems arise when there is a crack in the exchanger because many furnaces burn one substance to create more heat and often times there are harmful chemicals released in this process. If there is a crack in your heat exchanger chemicals such as nitrous oxide, carbon dioxide, carbon monoxide, and even just pure carbon, could be flowing through this system and out into your home. These chemicals can cause illness in small doses and even prove fatal in extreme exposure.
So if you notice a crack, what do you do?
Call a service technician immediately. More often than not, a cracked heat exchanger will require replacement of either the heat exchanger itself or the entire system, but it’s best to let a licenced technician inform you on this decision.
Considering the severity of the damage that can be caused by such a small crack, you are probably wondering why it happens and how you can prevent it. The cracks in a heat exchanger are much like the cracks you drive over every day on your city’s streets. Through the changing seasons, roads are constantly heated up and frozen solid. As a result, the road has shifts in size throughout the year. When the road is hot it expands and when it is cold it shrinks. Over time the material loses its ability to adjust to size changes and it cracks instead.
This same thing happens to your heating or cooling system.
When your HVAC system starts a cycle to heat or cool your house, these different temperature substances are constantly flowing through the heat exchanger forcing it to shrink and expand routinely. The exchanger becomes especially vulnerable to cracks when it must deal with extreme temperatures, hot or cold.
During extremes the material of the exchanger is forced to expand or shrink that little bit more and it can eventually pass its threshold and crack to relieve pressure. So, your best way to prevent this from happening is by limiting extremes and limiting cycles that your system must perform.
If your settings and/or system are improperly set to meet your home’s needs it may run an inefficient amount of cycles, creating more wear and tear than necessary. While extreme temperatures are often caused by a lack of air flow in your system trapping air in the machinery and making it work harder to meet your home comfort needs.
Both of these situations can be prevented by regular maintenance on your furnace.
Your Special Gas Services technician can diagnose these problems to create more efficient settings for your system and identify potential air flow issues within it. For air flow, it could be as simple as using a different or new filter, or as sophisticated as improper duct sizes or fittings.