Corrosion In Air Conditioners

Corrosion can cause your air conditioner (AC) to malfunction and even lead to the AC's premature failure. Below is an overview of corrosion problems in ACs.


Various things can cause corrosion to different AC parts, but the following are some of the most common causes of AC corrosion.

Moisture Exposure

Corrosion occurs when metal reacts with oxygen, usually in the presence of water. Therefore, exposure to water, in all its various forms, increases the risk of corrosion to the AC. Moisture can come from high humidity, melting snow, AC condensation, flooding, and even rainfall, among other sources.


Some chemicals cause or accelerate corrosion. For example, acidic chemicals cause corrosion much faster than even moisture itself. Unfortunately, many of these chemicals are abundant in most homes. For example, household cleaning products contain acidic chemicals (such as ammonia). Other products that encourage corrosion include paint, pesticides, glues, and many other everyday things.

Pet Pee

Lastly, you should also worry about corrosion triggered by pet pee if you have pets. The common culprit is the dog, which likes to pee on things such as the outside unit of the AC. If that happens, the pee (that is acidic) will trigger corrosion on the metal coils that cool the refrigerant.


A corroded AC is not easy on the eye, but aesthetic concerns are not the only things you need to worry about if your AC is corroded. Below are some dangerous consequences of AC corrosion.

Refrigerant Loss

Corrosion will reduce the thickness and weaken of the refrigerant lines without intervention. The weakened areas can develop cracks or holes that can allow refrigerant to leak. Low refrigerant levels can lead to complications such as energy inefficiency, overheating, poor cooling, and frequent AC breakdowns, among other problems.

Coil Inefficiency

Corrosion that covers the AC coils reduces the efficiency of the coils. The coils need to be clean to allow heat exchange between the refrigerant and the air. If the coils are covered in corrosion, the corrosion acts as an insulator and reduces heat exchange, which leads to impaired cooling.

Electrical Malfunctions

Lastly, extreme corrosion can also lead to electrical malfunctions. This happens if the corrosion spreads to electrical parts of the system, such as the motor and thermostat. The corroded conductors will experience increased resistance since corrosion doesn't conduct electricity as well as non-corroded metal.

Corrosion rarely causes sudden AC failure; it's a problem that creeps up on the AC. Therefore, prompt intervention by a professional technician can help you avoid the complications associated with the problem. To learn more, contact your local air conditioning service company