How to Prevent and Clean HVAC Coil Corrosion

October 27, 2018

Living in Monmouth County, you’re probably familiar with the corrosive effects of salt-laden Atlantic air on exposed steel and iron. You may not realize that the copper coils inside your outdoor and indoor HVAC units can also corrode over time, which can leave you facing an expensive equipment replacement.

Understanding Coil Corrosion

When the copper condenser coil housed in your outdoor HVAC unit is exposed to chloride or fluoride in the air, rain, and chemical cleaners, pits will develop in the metal. Indoors, volatile organic compounds (VOCs) — like formaldehyde that are released from structural components, pressed wood furniture, fabrics/textiles and numerous household products — can deteriorate your evaporator coil. When such compounds contact the coil surface, they oxidize into acetic and formic acids that etch the metal.

Eventually, both kinds of corrosion will cause tiny holes to form in your cooling coils, and refrigerant will leak out. You’ll see a steady decline in the equipment’s efficiency, an increase in your energy bills, and find it more difficult to keep your home comfortably cool.

Preventing Coil Corrosion With Cleaning

Once corrosion-related refrigerant leaks occur, you’ll need a new coil, which typically means replacing both main components of your HVAC system. Preventive maintenance that includes cleaning the coils can help keep corrosion at bay, and prolong the useful lifespan of your HVAC equipment. Cleaning the HVAC coils is a task best left to an experienced professional who has the skills and equipment to do a safe, thorough job using a product designed to neutralize damaging chemicals and acids.

There are other steps you can take to help prevent corrosion:

  • Use the hose to gently wash the outdoor coil once a month to slow down the buildup of chemicals and acids.
  • If your home is well-sealed for efficiency, consider having an air cleaner added to your HVAC system, or installing a whole-house ventilator unit to help eliminate trapped VOCs.
  • Have your HVAC technician apply an anti-corrosive coating on the coils after cleaning.

For personalized advice about preventing coil corrosion in your home’s HVAC system or to schedule maintenance, contact us at Aggressive Mechanical Contractors.

Our goal is to help educate our customers in Monmouth County, New Jersey and surrounding areas about energy and home comfort issues (specific to HVAC systems).