Building An Addition: A Homeowner's Guide

Tips For Protecting Your Air Conditioner From Two Common Warm-Weather Pests

by Toni Richards

With the spring season bringing warmer temperatures, it's also the time of year when many insects start to emerge and look for new places to nest. Your home's central air conditioning unit is a popular destination for this, particularly if it's dormant until summer. Understanding the most common threats to your air conditioner will make it easier for you to prevent or combat the problem. Here are two of the most common types you might find in the air conditioner and what you need to know about them.


Wasps start to come out just as the weather begins warming up, so chances are it's not yet warm enough to run your air conditioner. They often seek small spaces, and air conditioning condensers are full of those. Unfortunately, if they nest inside the condenser, you're likely to draw them into the house when you turn your AC on for the first time. In addition, wasps can be destructive to the inside of the air conditioner, costing you much more in repairs and maintenance.

You can combat this to some extent by having your air conditioner cleaned by an HVAC service technician in the early to middle of spring. However, you may want to add more deterrents. Hanging a decoy nest by your air conditioner will help to discourage wasps from nesting in the air conditioner. They don't nest too close to others, so that can keep them away.

Water traps are a great choice if you have found wasps hovering near your air conditioner. You fill the trap with some sugar water and hang it by the air conditioning condenser. When the wasps fly in to get the water, they cannot fly out.


Ants are drawn to electromagnetic pulses. That makes your air conditioning condenser a popular place to nest. The downside is that ant colonies are large, and they can damage the electrical boards and sensitive parts inside the condenser. This can be costly to repair, and severe damage may require a complete replacement.

Keeping the condenser serviced regularly will discourage ants from nesting because the colony would be disturbed before it really has a chance to settle in. You can also treat the area with boric acid baits. Mix some jelly or honey with a couple of teaspoons of boric acid. Put that mixture into shallow caps and place them around the condenser. Replace them as needed until you can have the condenser serviced.

You can also use the planting space around your air conditioner to discourage ants. Plant things like mint around the unit to keep the ants away, as the smell of it is a natural deterrent.

Being proactive about cleaning and maintenance with your air conditioner will help keep these pests at bay, but knowing which ones are a risk and how you can handle them will help you to be prepared. For more information, visit websites like