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Fox Family Heating & Air Conditioning technician working on a Mitsubishi Electric mini-split outdoor unit

Should You Cover Your Outdoor AC Unit During Sacramento’s Rainy Season?

Written by zeeshan@advantage-services.com on . Posted in Uncategorized.

As summer draws to a close, most homeowners switch off their ACs and start preparing for colder weather. Before you set aside your AC for the year, there are a few proactive steps you can take to protect it during the rainy season. 

When wintertime arrives in Sacramento, it can bring along rain, wind, leaves, and debris. While many homeowners reach for a full AC cover to address these issues, a cover can often cause more problems than it helps. To learn more about why covers generally aren’t needed and how to care for your AC, read on.

Outdoor AC Units Are Built To Handle Rain

While a pail might rust when it’s left outside, condensers are less likely to have an issue. AC manufacturers design condensers so that they can handle outdoor weather without becoming rusted or corroded. On its own, rain is unlikely to damage the unit.

The entire design of the coil, cabinet, fan, and electrical components is made to withstand rain. Electrical components and wiring are properly insulated, so they can safely manage normal exposure to outdoor rain and moisture. Unless you have major flooding or storm damage, your outdoor unit should be able to handle wintertime weather without a problem.

When Covering an AC Unit Can Cause Problems

Installing an AC cover can lead to a few issues. As a homeowner, it’s generally better to skip the cover and opt for professional AC maintenance instead.

It Traps Moisture

Rather than protecting the AC, a cover can counterintuitively cause added harm. Full covers can trap moisture, especially if they weren’t designed with breathable fabrics. Once moisture is stuck inside, the unit can develop rust, mildew, and corrosion.

Pests Can Take Up Residence Inside the Unit

Because a cover creates a space that is protected from the elements, it can attract pest infestations. Ants, wasps, spiders, and mice can move into the unit, leading to an unpleasant surprise when you uncover it in springtime.

Covered Units Present an Operational Risk

After having the AC off for the winter, it’s easy to forget that it’= is covered up. If a family member switches the AC on without removing the cover, it can damage the unit and lead to costly repairs. The cover limits airflow and causes the unit to overheat quickly, potentially resulting in a frozen coil and damage to the compressor.

When a Partial Cover May Be Helpful

While a full cover can damage your unit and result in pest infestations, a partial cover offers a few benefits. By installing a top-only cover, you can keep leaves, branches, and debris out. Because the cover is only on the top of the AC, it ensures better airflow. Pests are also less likely to take up residence in the unit.

However, a top-only cover can still cause damage if it isn’t used appropriately. For the best results, homeowners should never use plastic tarps or airtight covers. Both of these design options can trap moisture and lead to corrosion. Whenever possible, we recommend using manufacturer-approved covers and breathable materials.

The best time to add a top cover is after you are completely done using the AC for the summer. This helps to reduce the likelihood that someone turns on the AC with the cover on, protecting your AC from overheating.

What Sacramento Homeowners Should Do Instead

As a general rule, we don’t recommend using a full cover on your outdoor air conditioning unit. Instead, homeowners should perform the following maintenance activities to keep their ACs functioning at their best. 

  • Clear Debris: Periodically, you should clear any leaves or debris that are around the outdoor unit. There should be 2 to 3 feet of clearance from debris to ensure proper airflow. Additionally, the AC should be installed at least 1 to 2 feet from your home.
  • Clean Your Gutters: If your gutters have debris buildup, it can cause water to drop on the AC unit and increase the likelihood of corrosion. Clean gutters protect your AC and home from water damage.
  • Direct Water Drains Away From the Pad: Your AC is set up with a condensate drain line that carries water away from your home. To avoid pooling water around your AC or home, the drain line should be installed so that it directs water away from the AC pad and your home’s foundation.
  • Trim Vegetation: Whenever you mow your lawn, you should make sure to trim vegetation that is around the outdoor unit. For easier care, some homeowners use gravel or pavers around their outdoor unit.
  • Schedule Maintenance: One of the most important things you can do to protect your AC is to schedule routine maintenance. Timely heating, ventilation, and air conditioning (HVAC) maintenance can prevent major repairs. During the maintenance appointment, our team will clean the unit, lubricate moving parts, and inspect each component. Routine maintenance can prevent issues from happening and detect problems early, so you can spend less money on repairs.

Never Run Your AC While It Is Covered

One of the most important things to remember is to only use the AC cover when your unit is off for the winter. Never run your AC when it is covered.

A covered unit can restrict airflow, leading to overheating. In the short run, this can cause AC shutdowns and poor AC performance. Before long, the poor airflow and overheating can damage the compressor. 

If you decide to use a cover during the wintertime, make sure to remove it before you switch your AC back on. You should also clean the coils, replace your indoor filter, and look for any signs of damage before running your AC for another year.

Signs Rain or Debris May Have Affected Your AC Unit

Over time, rain and debris can damage the AC. If you notice any of the following symptoms, it’s time to schedule professional AC repairs.

  • Strange Noises: When you hear loud rattling or buzzing noises, it may be due to debris entering your AC unit. Alternatively, the fan blades or motor may have been damaged by the wind.
  • Frequently Tripped Breakers: If your breakers keep tripping after being reset, you should immediately stop using your AC. This indicates an underlying electrical problem, which can be caused by rain and debris damage. It can also be due to other factors as well, so a professional inspection is necessary.
  • Poor Cooling Performance: An outdoor unit can experience blocked airflow if there is debris inside the unit. This can result in poor cooling performance.
  • Standing Water Around the Outdoor Unit: If you notice standing water around your outdoor unit, rust, corrosion, and mildew may already be damaging your AC. It is not safe to use an outdoor unit that is surrounded by water. Call our HVAC team for an inspection. While you wait, remove the water and let the unit dry completely if it is safe to do so.
  • Visible Rust: Any signs of rust or corrosion are indications that rain may have already affected your AC unit. To avoid performance issues and costly repairs, these problems need to be addressed right away.
  • Bent Coil Fins: Debris can cause bent coil fins, which impact the airflow around the coil. As a result, your AC has to work harder to transfer heat, requiring more energy consumption.

Prepare Your AC for the Rainy Season

In Sacramento, outdoor air conditioning failures are more commonly associated with age, lack of maintenance, restricted airflow, or component wear than with normal rainfall. Using a cover can block airflow and trap moisture, leading to corrosion and decreased efficiency. Eventually, these issues can cause components to stop working.

If you are concerned about your outdoor unit, Fox Family Heating & Air can help. Our team can inspect, clean, and prepare your outdoor unit so that it is ready when the next cooling season arrives.

Learn more by scheduling your AC cooling services today. 

FAQs

Can rain damage my outdoor AC unit?

Your AC is designed to be extremely durable. Electrical components and wiring are insulated from moisture, so they aren’t affected. In most cases, rain is only going to be a problem if it remains trapped against your outdoor AC unit for extended periods of time.

Should I cover my AC unit in winter?

In general, covering your AC is not necessary. Your outdoor unit is designed with materials, paints, and components that are able to withstand rain. The bigger risk is from dirt, leaves, and debris clogging the unit and trapping moisture. As a part of shutting your AC off for the year, this debris should be removed.

What kind of AC cover is safest?

An outdoor AC cover is not necessary. If you do use a cover, it should be designed with a breathable fabric that prevents moisture from building up next to the unit. There are mesh and polyester top covers that are expressly made for ACs. Never use plastic or DIY covers because these can trap moisture, leading to corrosion and electrical failures.

How much clearance should my outdoor unit have?

Ideally, the unit should be at least 1 to 2 feet away from anything else. Above the unit, there needs to be a minimum of 5 feet of clearance to ensure proper airflow. Throughout the year, you should clear debris, grass clippings, and plant matter that are within 3 feet of the unit.