Air Conditioning units outside a home

Air conditioning is a wonderful thing. It makes living in hot climates and summers more comfortable. However, air conditioning also has its drawbacks. Air conditioners have the potential to circulate contaminated air around your home, leading to health issues such as sickness and allergic reactions. These are commonly called “air conditioner allergies,” although this is something of a misnomer as the allergies in question are not from an air conditioner but contaminates around your home being circulated by an air conditioner. 

In this blog post, Cote’s Mechanical will be going over some causes of air conditioner allergies as well as potential ways to help prevent them. 

Air Conditioner Allergies

A woman adjusts the AC temperature while her husband looks on

Using an air conditioner should make people more comfortable, not sick. Unfortunately, running an air conditioner can cause allergic reactions and sickness. This happens when an air conditioner circulates air with contaminants throughout a home.

What Are Air Conditioner Allergies?

There are many things around a home that can bring about air conditioner allergies. Below, we’ve compiled a list of common allergies spread by air conditioning that is by no means conclusive.


Pollen comes from plants and is a common allergen. Pollen can enter homes from open doors and windows but can also be carried indoors in a variety of ways, such as on clothing and shoes. Indoor plants can be another source of pollen.

Mold and Mildew

Exposure to mold and mildew can result in disease and allergic reactions. Mold and mildew can be dangerous if not dealt with correctly. Mold or mildew can develop in air conditioner units that have a humidifier, damp or wet cooling coil, or a condensation pan.

Pet Dander 

Some people are allergic to the proteins in pet dander. These proteins can become airborne and get circulated by your air conditioning system. If it’s possible, bathe your pet regularly to help reduce pet dander. You can also consult your doctor about receiving an allergy shot or medication to help deal with the allergen.

Dust Mites

Dust mites are microscopic organisms that are often found in homes. They can reproduce in warm and damp conditions such as air conditioners. Berkeley Lab states that a maintained relative humidity of 40 to 50 percent can help reduce the amount of dust mites.


Air pollution isn’t always outside – indoor air pollution can negatively affect your health. By using an air purifier or certain purifying plants, you can potentially reduce indoor air pollution.

According to the EPA, several pollutants that can affect indoor air quality include:

  • Byproducts of combustibles, including carbon monoxide, environmental tobacco smoke, and particulate matter
  • Lead, asbestos, and pesticides
  • Natural substances such as radon, mold, and pet dander
  • Mold and other biological agents
  • Ozone from certain air cleaners
  • Volatile organic compounds from different materials and products

Virus and Bacteria

Bacteria and viruses can enter homes or buildings through people, animals, plants, and soil. Some airborne viruses and bacteria are airborne and can be circulated throughout your home via your air conditioning system.

Several types of airborne bacteria and viruses include:

  • Influenza
  • Measles
  • Chickenpox
  • Legionella 
  • Staphylococcus

Volatile Organic Compounds, a.k.a. VOCs

Volatile organic compounds, also known as VOCs, are the result of gasses being released. VOCs can come from a number of household sources, such as paint, furnishings, and cleaning supplies.

One way you can reduce VOCs in your home is by paying attention to what kinds of cleaning products you are using and looking into safer alternatives.

VOCs can come from multiple sources, including:

  • Paint
  • Pesticides
  • Cleaning supplies
  • Gasoline
  • Cigarettes
  • Printer ink
  • Markers

Humidity Levels

If your home’s air conditioning is set too low, this can result in humidity levels being too low as well. Low humidity can make allergy symptoms worse. Both high and low humidity can negatively affect your health. For example, a large amount of vapor in the air can provoke allergies. The E.P.A. recommends a humidity level of between 30 and 50 percent.

What are the Symptoms of Air Conditioner Allergies?

There are several physical symptoms that can be brought on by air conditioner allergies. 

Some of these include:

  • Dizziness
  • Shortness of breath
  • Fever
  • Digestive problems
  • Tiredness
  • Coughing 
  • Sneezing 
  • Watery eyes

Children, the elderly, and people with respiratory problems are more prone to airborne contaminants, but they can harm everyone.

If you are suffering from allergies, it’s a good idea to consult with a medical professional.

How to Prevent Air Conditioner Allergies?

Outdoor AC unit next to house

Below we will look at some steps you can take to help reduce air conditioner allergies in your home or building.

AC Filter Change

A dirty air conditioner filter can contribute to air conditioner allergies. By routinely changing air conditioning air filters, you can help make the air in your home cleaner. Not only can changing an air conditioner filter help to alleviate air conditioner allergies, but it can also help your air conditioner to function more efficiently. A more efficient air conditioner can translate into energy savings for you. By using HEPA air filters, you can filter a large amount of particles. Working with a professional, you can determine the right filter for your situation.

Maintain Humidity Levels

By keeping your humidity under 50 percent, you can help to reduce the growth of dust mites and mold. By utilizing air conditioning, a humidifier, or a dehumidifier, you can help to keep the humidity at the level you need.

Utilize an Air Purifier

An air purifier draws in air and takes it through a filter, removing some particles before releasing it into the air again. There are many types of stand-alone air filters on the market with different levels of efficiency.

HVAC System Cleaning

Over time particles like dirt and dust can build up in your HVAC system. This can contribute to increases in air conditioner allergies as well as your HVAC system operating less efficiently. A properly cleaned HVAC system can help with allergies and possibly save you some money over time.

Air Conditioner Maintenance

Regular air conditioner maintenance conducted by a professional can help with air conditioner allergies and possibly even other potential health issues. Not only can it possibly benefit your health, but a regularly maintained air conditioning unit may be less likely to require expensive repairs and also save you money by functioning more efficiently. 

Air Conditioning Services

Whether you need an air conditioner or HVAC system cleaned, maintained, or repaired, Cote’s Mechanical is up for the job. Our family-owned and operated company proudly serves Denton County, Texas, and the surrounding areas. We offer 24/7 emergency repair and inspection services. All of our work is 100% guaranteed, and we have an A+ rating from the Better Business Bureau. Our team looks forward to helping you with your air conditioner allergies.

Contact us for HVAC services such as cleaning your air conditioning or HVAC system.

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