Making your A/C system work for you

To ensure your A/C system is working as efficiently as possible, here are some things you can do to get the most for your energy dollars: 

Check your thermostat

  • Cool your home at 78° or warmer with the thermostat fan switch on "auto." For additional savings, raise your thermostat to 82° or warmer when you're away from home.
  • When on vacation, cool your home at 85° with the thermostat fan on "auto," to help prevent mildew from developing (in most homes).

Use fans

  • Reduce your A/C costs and keep your home comfortable by using inexpensive, energy-efficient ceiling fans to circulate the air. This will allow you to set your thermostat higher and still feel cool.
  • Turn off your ceiling fan when you leave the room. A fan that runs all the time costs about $7 a month.
  • When buying a fan, choose the right size for the room. For example: 
    • 10' x 10' room or smaller = 36" fan
    • 15' x 20' room = 52" fan
    • Rooms larger than 15' x 20' = two 52" fans

Keep your unit clean and clear

  • Learn where your A/C filter is.
  • Change the filter regularly using the proper size, or clean it monthly.
  • Keep leaves, shrubbery and debris at least 18 inches away from your outdoor unit to avoid blocking the airflow.

Maintain proper airflow through your system

Keep the interior doors and vents open to help your A/C circulate air more efficiently.

Keep sunlight out during summer months

Close your blinds, drapes and shades during the hottest time of day.

Window Shading

Windows and glass doors that face east and west are the most prone to letting unwanted heat into your home. Here are some ways to shade the area:

  • Landscaping - You must plan before you plant. Consider the mature size of plants and their distance from power lines.
  • Awnings - These work best when the sun is high in the sky. They shade windows well but are not cost effective based solely on energy savings.
  • Window Coverings - These reduce the amount of heat that enters from the sun. They shade windows well but are not cost effective based solely on energy savings.

Install or upgrade insulation

  • Install or upgrade insulation in your home, especially if it was built before 1982, to help reduce your cooling costs and make your home more comfortable.
  • Visit our Guide to Insulating Your Home to determine if your home would benefit from adding insulation.

Consider buying a new A/C unit

  • If your system is over 10 years old, has undergone frequent repairs and still doesn't keep your house cool, it may be time to purchase a new unit.
  • FPL's A/C Program can help you when shopping for a new system. Visit our online A/C Buying Guide and list of participating independent contractors to help you buy a high-efficiency system that's right for your home.

Stay warm and keep your bill low in the winter

Extreme cold weather is rare in Florida and the heating systems in many Florida homes are inefficient and can cost a lot more to operate. In fact, strip or electric resistance-based heating requires two to three times more energy than air conditioning. Please use these tips as your guide to staying warm and keeping your bill low in the winter:

Set your thermostat as low as comfortably possible

  • For every one degree that you lower your thermostat during colder weather, you’ll save about 5 percent on your monthly heating costs.
  • Heat your home at 68° or cooler with the thermostat fan switch on "auto." To save even more, lower your thermostat to 65° or cooler at bedtime or when you're away from home.

Keep your filters clean

Clean or replace your air conditioner’s filter every month to trim your heating costs and help your unit run more efficiently.

Reduce air leaks

Seal doors and windows with weatherstripping or caulk.


This is an inexpensive solution to help reduce the amount of air that enters or escapes your home through doors and windows. Types of weather-stripping include:

  • V-shaped vinyl
  • Adhesive-backed foam
  • Spring metal
  • Door sweep


Caulking is an additional way to reduce unwanted airflow. It is only worthwhile when done as part of another project, such as painting. Use silicone or siliconized acrylic caulk because they have the longest life span, work well on most surfaces, and will maintain their elasticity.

Take advantage of the sun’s heat and light

Keep your south-facing windows clean. Open curtains on south-facing windows during the day and close all curtains at night.

Take shorter showers and use an efficient showerhead

People tend to take longer showers in colder weather, which increases water heating costs, so try to make it brief and remember to use a low-flow showerhead.

Take the Showerhead Test

Here's an easy way to determine if your showerhead is water efficient. Take the showerhead test.

  1. Get a bucket and a watch/clock that counts seconds.
  2. Place the bucket underneath the showerhead.
  3. Turn the shower on all the way using cold water.
  4. Time how long it takes for one gallon of water to fall into the bucket.

Check Your Timing

If it takes:

  • Less than 24 seconds to fill a gallon of water, then you do not have the most efficient showerhead because its flow exceeds the recommended 2.5 gallons per minute.

More than 24 seconds to fill a gallon of water, then you have an efficient showerhead.

Turn down the temperature on water heaters

Most water heaters are set to 140 degrees, but at 115 to 120 degrees you’ll still have plenty of hot water.

Provide good insulation

Insulate hot water pipes and, if your water heater is more than seven years old, consider a “wrap” to insulate the tank.

Add insulation to your attic

Adding insulation to your home can reduce your heating and cooling costs. If your home qualifies, we can help with some of the costs.

Swimming pools typically require less filtration in winter

Reduce the time you run your pool pump by two hours a day and you could save $8.21 per month.

Take an Online Home Energy Survey

FPL's Online Home Energy Survey gives you a personalized savings plan filled with energy-saving tips and recommendations based on your unique patterns of energy consumption.