Industry Insight – What About Coil Corrosion?
My guess is that you’ve probably heard about coils before. But are you aware of coil corrosion? Coil corrosion is an expensive problem in the HVAC industry, resulting in the need for coil replacement or full system replacement. According to CED Engineering, corrosion is responsible for about 40% of equipment failures in industrial applications. That’s a fairly scary number.
So What is Coil Corrosion?
Coil corrosion comes in the form of either pitting, which is visible, or formicary deterioration, which is invisible. Corrosion may be apparent within a few weeks to a few years, depending on the environment. Facilities located in potentially corrosive outdoor environments like seacoast, heavily populated urban areas, or are exposed to various threats of salt laden corrosive elements, various air borne molecular contaminants (AMC) and high relative humidity are more likely to be affected.
Exposure to fluoride and chloride causes pitting. Fluoride is in many municipal water supplies, while chloride is a part of ice melts, cleaners and fabrics. The result of pitting is pinholes, and then leaky coils.
Formicary corrosion comes from exposure to acetic or formic acids. These acids are everywhere – from household cleaners, to glues, paints, plywood and more. As we mentioned earlier, this kind of decay isn’t always visible, although it does sometimes appear in the form of a dark blue-gray or black deposit. This kind of corrosion creates tunnels within the tubing that result in pinholes forming in the coils, again often leading to a refrigerant leak.
What Are the Symptoms of Corrosion?
Typically, because of the refrigerant leaks, corroded coils will result in reduced efficiency, unattractive surface deterioration and equipment failure. The more noticeable result is an uncomfortable temperature. Due to leaking refrigerant, the system’s cooling capacity is decreased, resulting in a struggle to keep the temperature comfortable.
How Can You Prevent Corrosion?
To fight corrosion, manufacturers are coating metals before production. You can also purchase aftermarket coatings. Coating types include polyurethanes, epoxies, fluoropolymers and silanes. Each coating type has its own distinct advantages and disadvantages. In addition, you can also prevent corrosion — and a lot of other problems — by a regular checkup and cleaning. That means having your coils cleaned at least twice a year.
From here, you may be wondering what you can do next. If you have the time, you can research coil coatings and cleaners. Otherwise, you are welcome to delegate the dirty work to us. 🙂 Contact us about a coil checkup! [email protected]