The Importance of Preventing HVAC Coil Corrosion

The Importance of Preventing HVAC Coil CorrosionPreventing coil corrosion is far preferable to the alternative. Air conditioner refrigerant leaks due to advanced corrosion of an indoor evaporator coil or outdoor condenser coil are generally non-repairable. Due to the substantial expense of coil replacement, however, installing an entirely new A/C may actually turn out to be more financially viable. Therefore, when preventing coil corrosion can be accomplished by routine maintenance, it makes good economic sense.

What’s Corroding Coils?

Both the indoor and outdoor coil incorporate copper tubing that circulates refrigerant. Though efficient for heat transfer, copper is a reactive metal that is sensitive to certain chemical vapors which, when mixed with moisture such as condensation, form corrosive acids. Indoor pollutants include common VOCs (Volatile Organic Compounds) like formaldehyde as well as fumes from cleaners, paints and aerosol sprays. Outdoors, sulfur and nitrogen dioxides from vehicle emissions as well as other industrial air pollution, acid rain, and even salty ocean air are linked to accelerated coil corrosion.

How To Prevent It

Sealed inside the indoor air handler, the evaporator coil isn’t a candidate for DIY service. However, as part of annual cooling system maintenance, a professional HVAC service technician can access and clean coil surfaces, using cleaners specifically formulated to neutralize acids that degrade copper. The same procedure is applied to the outdoor condenser coil.

Since the outdoor coil is more readily accessible, a do-it-yourselfer can also augment annual professional cleaning by flushing the coil with water twice a year.

  • Shut off power to the outdoor condenser at the main power switch, usually located on the wall next to the unit.
  • Remove screws securing side panels of the unit as well as the top grille.
  • Spray water from a garden hose from the inside of the condensing unit first, directing the spray through coil fins to the outside. Then, from the outside, spray inwards through the coil.
  • Allow the coil to air dry, then reinstall side panels and top. Restore electricity.

Schedule annual maintenance for preventing coil corrosion with the professionals at Paitson Bros. We’ve been the Wabash Valley choice for HVAC sales and service since 1922.

Our goal is to help educate our customers in Terre Haute, Indiana about energy and home comfort issues (specific to HVAC systems). For more information about other HVAC topics, download our free Home Comfort Guide or call us at 812-645-6859. 

This entry was posted in HVAC System and tagged , , . Bookmark the permalink. Post a comment or leave a trackback: Trackback URL.

Post a Comment

Your email is never published nor shared.

You may use these HTML tags and attributes <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

What is 0 + 0 ?
Please leave these two fields as-is:
  • Click Here, For
  • » Call Us: 1 (812) 232-2347

  • How Can We Help?

    We're glad to answer questions... just click below for our contact form:

    Free Estimate

    Schedule Service

  • Recent Posts

  • Topics




  • Life's Journey &quo...
    By Jeff Paitson
  • About Jeff

    Jeff Paitson Jeff Paitson is a third generation business owner who continues to run the business with the same values that have been passed down from previous generations since 1922.

    Jeff’s belief is that the business belongs to Jesus Christ; therefore 10 percent of the company’s profits go toward the Maryland Community Church.

    Jeff is a Terre Haute Chamber of Commerce member and in his spare time, he enjoys photography.
    More »
  • About Ethan


    Ethan Ethan Rayburn is a lifelong resident of Terre Haute and a 2005 graduate of Purdue University.

    An Eagle Scout, Ethan spent four years as a non-profit executive with the Boy Scouts of America before joining Paitson Bros. as a comfort advisor and later General Manager. In that role, Ethan has brought a renewed enthusiasm for customer care, integrity, value, and service to Paitson Bros. Heating & Air Conditioning.

    Ethan enjoys singing and was a member of the Purdue Varsity Glee Club. He also enjoys playing and coaching soccer, spending time with his family and two young boys, and volunteering his time and resources with his church, Terre Haute First Baptist Church, which he has attended from a very young age.
    More »