Should I cover my HVAC unit in fall and winter?

Pros of Ductless HVAC Systems

One of the most common questions from HVAC owners is: should I cover my unit during the fall and winter seasons?

When the weather becomes cooler, you might be wondering if you should protect your unit by covering it up for the holidays. There are both pros and cons to covering your unit, but ultimately, it is your decision. Below, we go over the reasons why covering your unit during the fall and winter seasons may or may not be a good idea.

Your HVAC is built to withstand the elements

Modern HVAC systems are designed to withstand extreme weather conditions. Their condensers, or the part of the air conditioner that sits outside, are durable enough to hold out against snow and rain. Inside, the unit has coils, connections, and other mechanics that can endure extreme temperatures. Because HVAC units are made using high-quality materials, it’s usually unnecessary to cover them during the fall and winter months.

Pros of covering your unit

• It shields the unit from debris.During fall, debris such as leaves, twigs, sticks, yard waste, and others might fall into your unit. Keep your unit free from blockage so that it won’t run into problems when you use it again during the warmer months. Aside from causing efficiency problems, no one wants to spend the holidays cleaning up their unit.
• It prevents freezingWater can drip into your unit during winter, which can be damaging to your system especially it freezes. While most units can automatically thaw out the ice, if it has frozen over coils and other components, you’re looking at serious repairs. In warmer months, this isn’t a problem. Rainwater can actually help flush debris out.

Cons of covering your unit

• It invites critters.During colder seasons, small animals like mice and squirrels seek warm places to hide. If you cover your unit, you’re inviting them to turn it into their home for the holidays. While this might seem “cute”, they can destroy your unit by chewing through the wiring. Something like this can’t be fixed, so you’ll end up replacing the unit entirely.
• It is a fire hazard.You might forget that you covered the unit in the first place. Running a covered air conditioner is never a good idea This prevents proper airflow, and if your unit has a heat pump, could start a potentially dangerous fire.
• It traps moisture.The last thing you want to do is to create a high-humidity environment by trapping moisture inside your unit. Moisture can lead to rust and corrosion that can damage your electrical wiring, circuit boards, etc. It also leads to the growth of mold and mildew which are both dangerous to your health.

What should you cover it with?

If you insist on covering it, be sure to use covers that are breathable like mesh or canvas fabric. A DIY alternative could be plywood. It’s inexpensive and readily available. Cover only the top of the unit to keep leaves and twigs away. Don’t cover the sides so as not to create a humid environment.

Should you cover your unit?

Manufacturers don’t recommend covering your unit during fall and winter simply because the cons outweigh the pros. Your unit is well-built and durable enough to withstand harsh conditions, so there’s really no need for extra protection.

**Note: it’s very dangerous to run your outdoor unit, while covered. Keep in mind that a heat pump could be running all fall and winter. You should never cover a heat pump, and it’s recommended that you never cover an air conditioner either.