Should you cover the top of your air conditioner?

Quick answer

There are a few potential benefits to covering the top of your air conditioner unit:

• It can help protect the unit from weather damage like rain, snow, and debris.
• It may help the unit run more efficiently by blocking sunlight and reducing heat gain.
• A cover can reduce noise from the outdoor unit.

However, there are also some downsides to consider:

• The cover could trap moisture, leading to corrosion over time.
• It can prevent proper airflow if not designed correctly.
• The unit may overheat if the cover restricts airflow too much.

Overall, covering your outdoor air conditioner is generally recommended as long as the cover is made from breathable material and allows adequate airflow. Plastic sheeting or tarps are not a good option. When in doubt, consult your HVAC technician.

Why would you want to cover your AC unit?

There are a few reasons why homeowners may want to cover the top or outer housing of their outdoor air conditioning unit:

Protect from weather damage

Exposure to the elements can wear down your AC equipment over time. Rain, snow, hail, falling leaves, and debris can damage the coils, fins, and exterior housing. A cover protects the unit from this type of weathering. It helps prevent rust, corrosion, dents, clogs, and other issues that reduce performance and lifespan.

Improve efficiency

If the AC unit is exposed to direct sunlight and heat, it has to work harder to do its job of cooling your home. The condensing coils absorb unwanted heat from the hot exterior air. Blocking sunlight with an AC cover prevents solar heat gain, allowing the unit to run more efficiently. This can save energy and lower electricity bills.

Reduce noise

The compressor and fan of the outdoor unit make noise when running. An AC cover acts as insulation, absorbing some of the sound waves and reducing noise transfer to your yard. This is a great benefit if your AC is near windows or patios where noise would be disruptive.

Hide unsightly equipment

Let’s face it, AC units are not the most attractive backyard addition. Covering the equipment helps it blend in rather than being an eyesore. Covers come in neutral colors and unobtrusive designs.

Protect from pests and debris

An AC unit may attract pests like insects, rodents, or birds that can get into small spaces and cause damage. Nesting materials and critters that chew on wiring are hazards. A protective cover keeps pests out and prevents debris like leaves and seeds from piling up inside the unit.

Safety for pets and kids

Active pets or curious children may be tempted to climb on or play around the outdoor AC equipment. Sharp metal edges and electrical components make this dangerous. Covers form a barrier to protect kids and pets and prevent tampering.

What are the potential downsides?

While covers for AC units have benefits, there are also a few potential downsides to consider:

Moisture buildup and corrosion

If condensation and moisture gets trapped under the cover, this accelerates rust and corrosion. Breathable fabric covers are essential to allow water drainage and airflow. Plastic sheeting traps moisture and can damage the system.

Blocked airflow

Air conditioners require good airflow across the coils and condenser to exchange heat effectively. An improperly fitted cover that presses on the housing or seals it off completely blocks this vital airflow. The unit will not perform properly if starved for airflow.

Overheating issues

Related to airflow obstruction, restricted airflow prevents hot air from escaping from around the unit. The condenser coils absorb heat—if air can’t circulate, heat builds up and the AC may overheat or shut off on safety overloads.

Difficulty accessing unit

Covers can make it harder for technicians to access the AC unit for repairs or maintenance. It may need to be removed seasonally or when work is required. Most are designed for easy on/off installation but it’s still an added step.

Added expense

Although AC covers are not hugely expensive, they are an added cost. For homeowners on a tight budget, it may be an unnecessary expense if care is taken to protect the unit in other ways. Proper placement, drainage, and maintenance may be enough.

How should you choose an AC unit cover?

Here are the main factors to consider when selecting an outdoor air conditioner cover:

Material

Breathable fabric like polyester is superior to alternatives like plastic, vinyl, or canvas tarps. The cover must allow moisture to escape and not trap condensation.

Ventilation

Look for covers with vents, mesh panels, or other openings that allow ample air circulation in and out. This is crucial for proper performance.

Size

Measure your AC unit and buy a cover specifically sized to fit. It should not press on the housing. Allow a few extra inches clearance.

Fasteners

Covers attach via straps, cords, or easy snap systems. Choose something durable that can withstand wind and resists unraveling.

Color

Neutral colors like tan, gray, or green help the cover blend in. Avoid bright or bold colors that stand out.

Weather protection

Check the cover’s waterproof rating and ability to handle sun, rain, snow, etc. Outdoor durability is important.

Quality and warranty

Look for reputable brands and well-constructed materials built to last. Good covers come with at least a 1-year warranty.

Price

Basic covers start around $30-60 but high-end versions run $100+. Make sure you get the right cover—cheaper is not always better.

Examples of good air conditioner covers

Here are three quality AC unit covers to consider:

Cover	Features
TR Industrial Dome Top Cover	Durable woven polyester Ventilated dome structure Drawstring and strap closure Weather and UV resistant
Camco Dual Vent Cover	Heavy duty polypropylene Reflective white color Ventilated for airflow Protects against all weather
AC Safe Universal Fit Cover	Fits most AC brands 80% shade protection Waterproof and UV treated Vented for proper airflow

These covers check the boxes of breathability, ventilation, durable fabric materials, and easy installation. Prices range from $20 up to $60. There are also higher end designer covers if desired.

What size cover is needed?

Air conditioner units are made in standard sizes. Common residential units are:

• Small: 24 x 24 x 28 inches
• Medium: 28 x 30 x 30 inches
• Large: 34 x 34 x 38 inches

Larger commercial units can be bigger. To get the right fit:

1. Measure your unit length, width, and height.
2. Check these dimensions against cover sizing charts.
3. Buy a cover at least 2-3 inches larger than your unit.
4. Rectangle or L-shaped covers fit around corners.

Air conditioner covers usually have some flexibility but shouldn’t be stretched tight. Give the unit space inside the cover. Measure carefully for best fit.

Tips for sizing AC unit covers

• Include exterior base or stands in measurements.
• Account for attached piping, gauges, valves, etc.
• Covers should not press on the unit or restrict airflow.
• Oversized is better than undersized.
• Consider future replacement units which may be larger.

With the right cover dimensions, the unit will fit securely inside and air will flow unobstructed. Size up if unsure.

How to properly install the cover

Installing an air conditioner cover is usually quick and easy:

1. Clean exterior of AC unit so cover fits flush.
2. Position cover over unit and pull to base.
3. Attach cords or straps through grommets.
4. Tighten cords and adjust cover as needed.
5. Ensure good drainage from drip pan.
6. Make sure vents and openings align.
7. Seal all entry points for pests.

The cover should fit snugly but still have some play. Straps can be twisted to tighten if it’s loose. Zippers, Velcro, or snap closures make installing and removing covers simple. Keep closures facing downwards. Place the cover over a totally dry unit—moisture underneath causes condensation concerns. Ensure water drains freely from the base. Getting the cover positioned correctly takes a bit of practice but most slide right on easily.

Tips for proper AC cover installation

• Check sizing and fit before permanently attaching.
• Align vents with the fan and openings.
• Angle drainage openings away from the house.
• Make sure the cover is squarely positioned.
• Avoid pulling too tight—some slack allows airflow.

With the right steps, your AC cover will protect the valuable equipment inside while allowing proper operation.

When should you install and remove the cover?

Central air conditioning units are designed for use in warm weather. In most climates, the covers are installed in spring and removed for winter:

Install in spring

Put the AC cover on before you turn on the system for summer as temperatures rise. This prevents spring debris and moisture from getting inside the uncovered unit. Early spring is ideal.

Remove in late fall

When it’s time to shut down the AC for winter, remove the cover after turning the system off. This keeps out fall leaves, sticks, snow, and winter precipitation if you get an unexpected warm spell. Late fall removal is best.

You may also install the cover in fall and leave it on over winter. This protects the idle outdoor unit from harsh winter weather. Just remember to remove it in spring before using the AC.

Seasonal removal tips

• Clean unit thoroughly before covering or uncovering.
• Inspect for any damage, leaks, or pests before storage.
• Make sure the unit is totally dry when putting the cover on.
• Don’t run AC with cover on or off with cover sealed.

Properly timing installation and removal avoids problems and keeps your condenser protected year-round. Some homeowners leave covers on year-round for maximum protection.

How much does an AC unit cover cost?

AC unit covers are relatively inexpensive. Here are typical price ranges:

• Basic polyester covers – $20 to $50
• Mid-range, better brands – $50 to $80
• Premium covers with more features – $80 to $150
• Custom fit or heavy duty covers – $125 to $200

Mini-split ductless AC covers and larger commercial unit covers cost more. Prices vary based on:

• Materials used
• Ventilation design
• Size of the unit
• Added features like insulation or reflective layers
• Brand name and quality

More expensive does not always mean better quality. Focus on the right size, materials, and ventilation properties when choosing.

Here are typical costs for materials:

Cover Material	Typical Price Range
Polyester	$30 – $100
Canvas	$50 – $150
Vinyl	$40 – $80
Acrylic	$70 – $170

Look for sales on AC covers in spring and fall. Avoid cheap plastic sheeting—the small savings isn’t worth potential moisture risks. With regular care, a quality cover lasts 5-10 years outside.

Conclusion

Adding a protective cover over your outdoor central air conditioning unit is usually highly recommended to extend its lifespan. The right cover blocks sun exposure, reduces heat gain, prevents weather damage, keeps out debris and pests, and dampens noise. This results in improved efficiency and cooling performance.

It’s important to choose a cover specifically sized to your unit that does not restrict vital airflow around the sides. Breathable polyester or acrylic with ventilation openings allows moisture to escape and is best. Proper seasonal installation and removal habits prevent problems. AC unit covers are an inexpensive way to protect a very expensive system from premature wear and tear. Your HVAC investment will last longer thanks to a quality exterior cover. Just take care that it fits properly and does not block air circulation based on the manufacturer’s guidance. With a tailored cover installed correctly, you’ll keep your condenser shielded from elements while allowing it to operate at peak efficiency for years of reliable cooling.