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Hedges, Debris, Mulch, Lawn Mowing: Tips to Protect Your Outside AC Cabinet

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“Olive, what does any of that in the title have to do with my AC?” Yes, I know you may not connect basic gardening with keeping your house cool, but taking proper care of your central air conditioner isn’t all about fretting over technical terms like R-22, R-410A, and THX-1138. (One of those isn’t an AC term at all, can you guess which?*) But activities you may not connect with the air conditioning system can have a big impact on it.

So … let’s get into protecting that outdoor condenser cabinet with good lawn and garden care. We don’t want you to need a new AC installation in Knoxville, TN just because of gardening mishaps!

Why the outdoor cabinet is so important

It’s easy to think of the outside cabinet of the air conditioner as a part that just takes care of itself. But the cabinet has several huge jobs in cooling the house. The compressor, the literal heart of an AC system, is in there. There’s also the condenser coil (the reason this cabinet is often called the condenser), which is where the AC expels the heat to the outside. If the coil can’t effectively release heat, the air conditioner won’t be able to work effectively or efficiently.

Here’s what this has to do with your lawn and garden

What can cause the coil to lose the ability to release enough heat outside? Dirt, grime, leaves, grass, bushes … any type of obstruction. A dirty coil or a cabinet that doesn’t have room to exhaust heat from the coils to the outside will restrict the operation of the AC. I’m going to go down our list to show what you can do to keep problems to a minimum.

  • Trim those hedges! Or bushes, or any shrubs or plants growing near the condenser cabinet. People often don’t like the general “look” of the condenser cabinet and try to hide it behind foliage, but this can be bad news! The cabinet needs a foot of clearance on all sides to do its job. Those plants can also send leaves into the cabinet to block the coil. If you’ve got plants growing closer than a foot, trim them and cut back those branches. The condenser needs a tidy area around it.
  • Watch out for mulch! Garden mulch close to the condenser is a fast way to get mulch on the condenser—specifically the coil. A layer of thick dirt on the coil makes it difficult for it to release heat. Keep any mulch away from the condenser.
  • Mow the lawn carefully! When you mow the lawn, plenty of grass clipping, as well as dirt and mulch, fly up into the air, and this can go straight into the condenser cabinet to dirty up the coil. The same for weed trimmers. My advice is to shut off the AC when mowing the lawn (the fan might draw objects into the unit) and pay attention to where the mower tosses out cuttings so you can angle it away from the unit.

Stay cool and garden with skill!