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Ask the Expert: Maintaining your A/C to cool your home efficiently

Ask the Expert: Maintaining your A/C to cool your home efficiently

by | Jun 28, 2018 | 0 comments

Can cleaning your A/C system really save you on energy cost?

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With temperatures quickly rising, it is important to ensure you keep your air-conditioner (A/C) maintained and you’ll not only save money on energy, but you’ll also extend its lifespan, saving money on costly early replacement. Now is the perfect time to get your A/C unit cleaned, serviced and ready for summertime.

Cleaning and replacing A/C filters
The most important maintenance task that will ensure the efficiency of your air conditioner is to routinely replace or clean its filters. Clogged, dirty filters block normal airflow and reduce the system’s efficiency significantly. With normal airflow obstructed, air that bypasses the filter may carry dirt directly into the evaporator coil and impair the coil’s heat-absorbing capacity. Replacing a dirty, clogged filter with a clean one can lower your air conditioner’s energy consumption up to 5%.

Clean or replace your air conditioning system’s filter or filters regularly, about every month or two. You may need to check and clear or replace your filter(s) more frequently if your air conditioner is in constant use, subjected to dusty conditions, or if you have fur-bearing pets in the house.

Dusty registers and vents
The air vents are an important component of your air conditioning system. If you look into your air vents or registers and see dust and debris, you may want to pull out the vacuum. Heating and cooling registers should be cleaned about once a year, but most people don’t think about them until they have to be removed for something like a painting project. Begin by dunking them in soapy water. A gentle scrubbing with a soft brush is all it takes to remove the dust and mildew that build up on the louvers. Then rinse them with clean water and be sure they’re completely dry, including the gasket on the back, before you re-install them. Keeping your air vents clean isn’t just essential to ensuring your home’s comfort, it’s also essential to ensure the air in your home is fresh and free of pollutants.

Cleaning your A/C evaporator and condenser coils
The air conditioner’s evaporator coil and condenser coil collect dirt over time. A clean filter prevents the evaporator coil from soiling quickly. In time, however, the evaporator coil will still collect dirt. This dirt reduces airflow and insulates the coil, reducing its ability to absorb heat. To avoid this problem, check your evaporator coil every year and clean it as necessary.

Outdoor condenser coils can also become very dirty if the outdoor environment is dusty or if there is foliage nearby. You can easily see the condenser coil and notice if dirt is collecting on its fins. Cleaning the area around the coil, removing any debris, and trimming foliage back at least 2 feet (0.6 meters) allow for adequate airflow around the condenser.

Clogged condensate drain
Taking the time to clean your air conditioner’s drain line (or the condensate line) at least once per year can have a great positive effect on how efficiently your system runs. Over time algae, mold, and mildew can build up inside the condensation drain line and form a clog, causing water to back up and overflow inside the A/C unit. To prevent this from happening, pour a cup of bleach in the access opening in the drain line near the A/C unit to kill any algae, mold, or mildew that has formed in the pipe. If the condensation line is clogged, you will need to use a shop vac or special pump to remove the clog from the line.

Hiring a professional
When your A/C needs more than regular maintenance, hire a professional service technician. A well-trained technician will find and fix problems in your A/C system.

The technician should:

  • Check for correct amount of refrigerant
  • Test for refrigerant leaks using a leak detector
  • Capture any refrigerant that must be evacuated from the system, instead of illegally releasing it to the atmosphere
  • Check for and seal duct leakage in central systems
  • Measure airflow through the evaporator coil
  • Verify the correct electric control sequence and make sure that the heating system and cooling system cannot operate simultaneously
  • Inspect electric terminals, clean and tighten connections, and apply a non-conductive coating if necessary
  • Oil motors and check belts for tightness and wear
  • Check the accuracy of the thermostat.

For a list of Participating Independent Contractors qualified to help you with your A/C maintenance needs, visit

No cost saving tips:

  1. We recommend setting your A/C to 78 degrees with the fan on “auto” to help you save. When you leave your home, consider raising the temperature to 82 degrees to save even more. Read more at and
  2. Use a fan to keep cool so you can raise your thermostat even higher. But, remember to turn the fan off when you leave the room. Read more at
  3. Close the shades, blinds and drapes to keep sunlight out.

More saving tips:

  1. If your A/C s is more than 10 years old, needs frequent repairs and doesn’t keep your home cool, you may benefit from a new high-efficiency A/C and you may qualify for a $150 A/C rebate. Read more on how to get the most out of your A/C this summer at
  2. Consider installing a smart thermostat to save up to $50 on your yearly energy bill. Learn more about smart thermostats at

Other energy saving tips and ideas when cooling your home

Maintaining you business HVAC system

Heating, ventilation and air conditioning (HVAC) systems are among the most energy-intensive mechanisms of any business and also the key driver for electricity demand. In fact, cooling of the work space alone accounts for more than a third of the energy used in commercial buildings on average. Many of the steps that business owners and managers can take to reduce costs require little to no expense and are also incredibly simple:

  • Change HVAC filters regularly – can help reduce wasted energy by 5-10%. Dirty filters overwork HVAC systems by restricting air flow, cost far more to use, lead to poor indoor air quality and result in far more HVAC maintenance issues and costs. HVAC filters should be changed every month. At the longest, they should be switched out every three months.
  • Perform regular quality maintenance – HVAC maintenance is like getting a tune-up for a car – both are necessary for top performance. Regular quality maintenance on all HVAC systems and equipment ensures that those systems and equipment are not wasting energy due to substandard, aging or faulty performance.Taking a proactive approach to a building’s HVAC systems through regular quality maintenance can significantly reduce maintenance costs. Finding an HVAC technician who can provide in-depth knowledge, work and advice is crucial to properly maintaining HVAC systems and equipment.
  • Ensure all heating and cooling ducts are properly sealed – Doing something as simple as properly sealing heating and cooling ducts can improve HVAC efficiency by up to 20% or more. Ducts can be sealed using mastic, foil tape or blown-in duct sealant, such as Aeroseal. The sealing effect is further improved by wrapping the ducts in insulation. Focus first on areas of the building that are unprotected – underneath the building or in unheated/cooled storage spaces.

Sometimes the best way to improve HVAC efficiency is to upgrade or replace the existing HVAC equipment and systems. Running HVAC systems and equipment that are past their suggested lifespans can lead to added energy and maintenance costs.

If a building’s air conditioner or heat pump is more than 10 years old, consider replacing it with ENERGY STAR-certified products. ENERGY STAR-certified air conditioners and heat pumps can improve sustainability and reduce energy costs by up to 20%. Furnaces or boilers that are more than 12 years old will also likely be due for upgrades or replacement, and ENERGY STAR-certified furnaces and boilers also offer significant cost and energy savings.

Retrofitting existing packaged rooftop HVAC units with demand controlled ventilation and energy recovery units are yet another important and successful ways for businesses to significantly improve energy efficiency.

About The Author

Jeanne Moral-Hernandez

Jeanne Moral-Hernandez is FPL’s Residential Air Conditioning and BuildSmart Program Manager. She has over 14 years experience at FPL. The Residential Air Conditioning program provides incentives to customers for installing eligible air conditioning equipment in their existing home.

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