Winter is coming, and it’s time to start thinking about how you’re going to prepare for the cold months ahead. If you live in a climate with cold, snowy winters, you may worry about damage to your air conditioner in the winter from snow and ice buildup. However, your HVAC unit was designed to withstand harsh conditions and cold temperatures. While it may seem like a good idea to cover your HVAC unit in the winter, it isn’t. Here are a few reasons why we don’t recommend it, and what you should do instead.

Covering Your Unit Traps Moisture

Covering your unit could cause damage from moisture buildup. If enough moisture is trapped inside the system that isn’t being released through normal operation — like when the condenser fan comes on — then this can cause corrosion on internal components like coils and fins.

Rusting occurs when moisture enters an enclosed space like a furnace or air conditioner. If you have a covered unit that’s not vented properly, this will happen much faster than usual.

It Encourages Mold Growth

When you cover your air conditioner or heat pump, you are encouraging mold growth. Mold can form on the inside of your unit if there’s condensation present. Not only is this unpleasant to look at, but it can also make you and your family sick.

In extreme cases, mold can cause respiratory problems and even lung infections. If you have allergies or asthma, covering your air conditioner can make these issues worse.

When the outdoor temperature is lower than indoors, there may be a risk of condensation. If there’s no airflow through your system because it’s covered, moisture will have nowhere to go, and it will stay wet longer, increasing the risk of mold and bacteria.

HVAC Covers Can Create a Nesting Area for Critters

In colder climates, animals often seek out warm environments to keep them warm and safe during the winter months. If they find an opening large enough to squeeze through, they may choose to nest inside your HVAC system. This can lead to problems over time as they could cause damage or even break down parts of the unit.

How Do You Winterize Your Outdoor HVAC Equipment?

Before winter hits, it’s a good idea to sweep away any leaves or lawn trimmings that have collected on or around the base of the outdoor unit. When you’re done, use a garden hose to wash any dirt or debris off the unit. If there are any leaves or other materials stuck in the fins on top of your unit, remove them and let everything dry.

Find the electrical supply switch and turn it off. This way, you will have to go and turn it back on manually and avoid it accidentally turning on during a warmer-than-usual day.

Wrap any exposed pipes or water lines with foam or pipe insulation. You should have already turned off the outside faucets and bled the lines and hoses, and this will keep any water from freezing inside the lines and causing leaks.

When Should You Cover Your HVAC System?

If your outdoor condenser sits in a spot where it is exposed to icicles from water dripping off the roof, this is the one instance where it is okay to cover it. You do need to protect it from objects like falling chunks of ice that could break off and damage the fins or other internal parts of the system.

But you should cover the top only, not all four sides. Find a piece of plywood that is the same size as your condenser unit’s top and place it squarely on it; two big rocks or bricks will keep it in place.

A more innovative alternative would be an elastic mesh cover with clips on the ends. The cover should reach no lower than 6 inches, leaving most of the unit open for airflow and to keep animals from nesting under it; this is especially important in cold climates.

Looking for heating or cooling installation, repairs, or routine maintenance in Modesto? Look no further than Honey's Air & Solar. We’ll help you choose the right solution to your problem — whether it’s a simple repair or a full-scale replacement. Our team works on furnaces, air conditioners, heat pumps, and ductless systems. We also offer indoor air quality, generator, ventilation, solar, and window replacement services. Contact us today for a free estimate.

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