You Aren’t Changing or Cleaning Your AC Filters
At a minimum, you should be changing the filter on your central AC unit once every three months—and as often as once a month if your system is running all the time.
Neglect this chore, and a dirty filter can lead to poor airflow or freezing up of your unit’s evaporator coil. A filthy filter could add 5% to 15% to your AC bill and will shorten the lifespan of your whole system.
You’re Not Having Your System Serviced Annually
You can look up online video tutorials about cleaning your AC unit’s coils and fins—necessary maintenance operations that keep your system up and running efficiently. You could also bring in a pro to service your system once a year.
You Don’t Have a Programmable Thermostat
A programmable thermostat can save you hundreds on your annual AC bill by automatically raising the temp at those times of day when you’re at work or away from home.
You’re Setting Your Thermostat Too Low
Research shows the human body is capable of adapting to hot or cool temperatures pretty quickly—like within a week or two. When you consider you’ll cut up to 3% off your AC bill for every degree you raise the temperature—it’s worth sweating through that adjustment period and setting your thermostat somewhere in the high 70s.
You’re Not Taking Full Advantage of Fans
Any type of fan, but especially ceiling fans, can help keep cool air circulating throughout your home. That removes some of the burdens from your AC system.
Your Thermostat and/or Vents Are Poorly Positioned
If the sun or a nearby lamp blasts your thermostat for big chunks of the day, that could throw off its readings and cause it to crank your AC even though your place is pleasantly cool. Blocking AC vents with furniture or curtains can also limit air circulation. You want to be sure your AC vents are unobstructed.
You’re Cooling Empty Rooms
If AC vents are open in every room of your house, you’re chilling a lot of real estates that may not be in use on a day-to-day basis. Walk around and close those AC vents that open onto unoccupied rooms. Also, closing closet doors ensure those spaces aren’t swallowing your cold air.
You Don’t Have Blinds or Curtains
Bright sunlight is your AC system’s nemesis. By closing blinds and sliding curtains to block the sun’s rays, you’ll also shield your space from the sun’s heat.
Source: Markham Heid, “8 Big Mistakes You’re Making With Your Air Conditioner”, Time Health