Every time I travel, my favorite part of coming back to Hawaii is stepping off the plane and taking a deep breath of the fresh, clean air. At home, I usually like keeping all of the windows open to let in the cool breezes. Lately, however, it seems as though those breezes have disappeared.

To keep cool, I’ve had to run the A/C unit all night, every night — and sometimes even during the day.

Window A/C units, like other appliances, require regular maintenance to operate in peak condition. This ensures that they’ll not only cool better, but also run more efficiently. To take care of your window A/C unit, remember to do these things:

• Check the filter. Once a month (or more, if you frequently use the unit or live in a highly dusty area) assess your filter to ensure it is not dirty or clogged. If it is, clean or replace it, depending on your model. This action alone can lower the unit’s energy consumption by 5 percent to 15 percent, according to the U.S. Department of Energy.

• Clean the coils. Over time, dirt and debris on both the evaporator and condenser coils can restrict airflow and get in the way of the cooled air. Vacuum the evaporator coils under your filter with your brush attachment. Repeat this with the condenser coils on the back of the unit. While outside, remove any foliage or barriers that might be restricting the airflow to the unit. The U.S. Department of Energy recommends trimming back at least 2 feet.

• Straighten the fin combs. The metallic blades that cover the back of the unit, called fins, sometimes can bend and reduce airflow. To get them back to optimal condition, unplug the unit, and then vacuum the fins to remove any debris. Comb them straight using a fin comb, which is available at your local hardware store for around $10.

• Unclog the drains. When the drain channels are clogged, the unit can’t effectively reduce humidity. The U.S. Department of Energy recommends occasionally passing a stiff wire through the drain channels to ensure they stay clear.

As always, check your manufacturer instructions for details that might be specific to your model. If you ever are unsure or feel uncomfortable, consult a professional.

Have a comment or question for Joanne? Email thefixisin-hawaii@gmail.com.