It’s true that on hot days your air conditioner may work a little harder. Just like people, it could seem a bit sluggish on a 90-degree day – and add the bonus of humidity, and your A/C unit may seem like it needs almost as much relief as you do. So, before the temps get too high, here’s the lowdown on how hot days affect your AC unit.


An air conditioner is basically a machine for heat exchange, it has to deal with air in two environments. First, by transferring hot air from inside the house to the outside air, and second, by conditioning the outside air to be cooler inside the house. On hot days that means your A/C needs to work twice as hard. Not only is there more heat coming into the home, which it needs to remove, but also the air outdoors is hotter, which makes it harder for your A/C unit to reject the heat.


Not only does heat affect how your A/C performs on a hot summer day, but humidity plays a major role as well. An excessive humidity level means your A/C will be working harder to get rid of that damp, clammy air. If your A/C unit doesn’t have the cooling capacity to handle it, you will feel the results on your skin.

Inspect the equipment

Furnaces, boilers and air conditioning units are usually hidden away in a basement or utility area. Does the equipment look like it is in good condition? Is it making odd noises? You probably won’t be able to make an accurate assessment of the system based only on how it looks, but you may notice something that concerns you. Be sure to hire an HVAC technician to perform a routine inspection of the equipment.

Do a quick air conditioning maintenance check-up:

  1. Replace all return air filters. Most need to be replaced every 30 days.
  2. Check the cleanliness of the outdoor air conditioner coil. Grass, dirt, and debris can clog it, severely reducing its efficiency and ability to cool your home.
  3. Turn the power off at the breaker or disconnect.
  4. Attach a spray nozzle to a garden hose and set it to a medium pressure
  5. With the nozzle pointed close to the coil, spray in an up and down motion, aiming between the fins. Do this for the entire coil.
  6. Allow the outdoor unit to dry completely before restoring power to the unit.
  7. Try once again to cool the home.

Quick Tip

Remember, if you are in the market to buy a new AC unit, pick one that suits the size of your home. Picking the proper size will be most effective. If it’s too big it won’t remove moisture from the air as effectively, because it won’t need to run as much, giving it less time to dehumidify your home.