The outdoor AC unit is designed to withstand most environmental elements. A check for rust and other potential issues with the well-being of your unit is just part of what an HVAC technician will perform during an annual visit. If the AC unit has not been well taken care of, this corrosion can easily set in, mostly in areas rich in moisture. This article will delve into the impact of corrosion on your AC unit and provide practical ways to deal with the problem.

Extent of Corrosion in AC Units

The first impression one would get from having a rusty AC unit is that it is merely an aesthetic issue. However, this is not the only damage corrosion can cause. It directly affects the performance of your air conditioning unit by taking longer to either heat or cool your home. The inefficiency can lead to higher energy bills. If left unchecked, rust will creep and spread over time to vital parts, causing damage that includes unexpected repair costs, system failure, and a much shorter life for your AC unit.

Knowing the Causes of Corrosion in AC Units

Corrosion results from the natural occurrence of metal oxidization, like steel or iron, when it reacts with oxygen and moisture over some period. The process is quite worrying in AC units since that might result in the deterioration of critical components of the appliance. Some of the significant causes of corrosion in AC units include:

Excessive levels of moisture

The primary source of rusting on the air conditioner is moisture caused by rain, condensation, or simply humid air. Air conditioners tend to suck in moisture from inside and then have it condense on evaporator coils, which drains out. However, if the humidity stays too long on equipment, it will cause erosion. A common problem is a clogged drain pan that causes water overflow, damaging many other air conditioner parts. Chemical fertilizers in plants close to the unit may also cause corrosion. Exposure to rain hastens this process even more.

Poor Maintenance End

Regular maintenance will help in preventing corrosion. A dirty filter of an AC can trap moisture and dirt, which will help form rust around coils. The outdoor units are mainly prone to dirt, dust, twigs, leaves, and other organic materials that get stuck in the condenser unit of the exterior part and reduce its performance. The drain system can clog and lock in moisture, providing the perfect environment for rust to form.

Age of the AC System

Like all other mechanical systems, air conditioners have average valuable lives, ranging between 10 and 15 years. Corrosion on the metal casing and other components of an AC system also increases with age.

Volatile Organic Compounds

These compounds can then be drawn directly into your AC system whenever they enter your indoor air and begin slowly corroding your copper refrigerant pipes. When this happens, the pipe starts to rust and causes some channels where refrigerant leaks occur, significantly reducing the AC system’s efficiency.

Environmental Factors

Environmental conditions significantly affect the corrosion rate and overall extent in AC units. This is particularly true in outdoor units constantly exposed to the elements. This similar risk also persists in industrial areas, where the pollutants and airborne chemicals can react with the metal components of the AC unit to bring about accelerated wear and tear. If this is not checked and a unit is exposed to it for a long time, it can inflict substantial damage on the coils, fins, and other essential parts of the unit, reducing its efficiency and increasing maintenance costs.

Electrochemical Reactions

Electrochemical reactions are another, perhaps less obvious, cause of corrosion in AC units. This is a class of corrosion termed galvanic corrosion, the result of contact between two dissimilar metals in an AC unit when an electrolyte, such as water, is present between them. These metals, usually aluminum, and copper, react in a way that one metal becomes an anode, which gets sacrificed or corrodes, and the other becomes a cathode. The net effect is a speedy dissolution of the anode metal, which can create leaks and structural weaknesses, resulting in system failure. Since these reactions typically occur within the inner components of the unit, they can be quite challenging to detect by the time significant damage has been caused.

Harsh Chemicals

Using harsh chemicals to clean or maintain the AC units may inadvertently contribute to corrosion. Cleaners that are highly acidic or alkaline disrupt the metal surfaces of the unit, destroy protective coatings, and expose the metal to the elements. For instance, while an intensely concentrated bleach solution may clean the drain pan, if it is not sufficiently diluted or rinsed off, it can cause various parts surrounding the pan to corrode. Moreover, chemicals in cleaning products, air fresheners, and some paints release volatile organic compounds, which can find their way into the AC unit and break down metal components over time. Continuously exposing such chemicals to the parts shortens the life span of your AC unit and may lead to expensive repairs.

Addressing and Preventing Corrosion in AC Units

Early handling can prevent more corrosion-related damage. Here are some steps to address and avoid rust on your outdoor AC unit:

Early Detection and Cleaning

If you start to see rust, you’ll want to act fast. First, turn off the circuit breaker that supplies the AC system. Take a circuit tester and ensure no power is provided to the unit. Then, remove the outdoor unit side cover with a screwdriver. This may take two people because of how light the side cover can be.

Try washing it off to clean the condenser unit, which you’ll recognize as a square or rectangular panel with coils and fins. Light rust is removable with a condenser coil spray. Just spray it on the condenser’s coils; as it foams up, it will cause the rust to loosen up. Since the condenser coils are delicate, gently brush off the remaining rust using a soft nylon brush.

Cleaning the Drain Pan

All the extra coil spray will drip into the drain pan, which must be kept clear to avoid corrosion in the future. Clean the drain pan with an equal parts mixture of bleach and water. Make sure that the drain itself is clear and the pan drains well. The pan should be cleaned periodically so that moisture will not accumulate, eventually causing rust.

Applying Rust-Proofing Measures

Apply rust-proof primer to the AC unit’s now exposed surfaces and then a coat of outdoor paint. This will protect it from moisture and other elements that will later cause corrosion to the metal parts.

Preventing Rust through Maintenance

Vigilance in maintenance is still the best defense against corrosion. This means cleaning the filters, seeing that drain lines are cleared, and trimming the vegetation that frequently overgrows around the outdoor unit. Regular checks by an HVAC professional can help prevent minor issues from becoming expensive and significant problems.

Read more on AC Unit Corrosion.

Corrosion in air conditioners runs deep. Researching related topics such as the effect of coastal environments, galvanization, and how a person can choose corrosion-resistant units would be very helpful in hanging on and thus lengthening the life of your air conditioning system.

The Role of Galvanization in the Prevention of Corrosion

This is one of the methods applied to metal components in AC unit manufacturing, which tends to fight off corrosion. However, an understanding of the workings of galvanization and its benefits in an actual sense is the way through which homeowners can make informed decisions about their AC systems.

The Impact of Coastal Environments on the Corrosion of an AC Unit

This will, in turn, increase the risk of corrosion of mechanical devices installed near the sea. Special precautions, such as using corrosion-resistant materials and frequent servicing, are needed so AC units in this environment can last a little longer.

How to Choose Corrosion-Resistant AC Units

When purchasing a brand-new AC unit, the material used for its body should always be considered. Coatings resistant to corrosion or components built with materials such as stainless steel or aluminum have a place in highly humid or richly chemical environments.

Wrapping Up

Corrosion is an essential threat to the efficiency and lifetime of your air conditioner. Regular maintenance is necessary to prevent rust formation by cleaning filters, blowing out drain lines, and protecting the unit from external elements. Early action against corrosion will save you from pricey repairs and extend the system’s life. If you notice signs of corrosion or need routine maintenance on your AC unit, contact your local HVAC company for professional help today and ensure your system keeps running effectively.