How can I be sure my older, recently serviced furnace is operating at peak efficiency? -Ruthie

Hi Ruthie,

There are a number of steps you can take to your furnace and home in general, that will allow you to get the most heating and cooling out of your HVAC system for the least amount of energy.

  • Home Energy Audit: Have an energy audit of your home conducted. You may be able to receive an energy audit at no charge from your utility company. If not, you can hire a private company to conduct one for under $300. An energy audit is a great way to find any problem areas that need to be addressed in your HVAC system and house. Read more data on how much energy audit can save you in our home energy facts and statistics guide.
  • Seal Ductwork: Make sure the ductwork for the HVAC system in your home is completely insulated and sealed. Older duct work has fiberglass insulation over metal pipes that may have gaps or leaks in joints and loose connections at registers. Use foil tape to seal joints, followed by a coating of duct mastic. Properly sealed ducts can cut your heating and cooling costs by up to 20%!
  • Replace Air Filter: Change your HVAC return air filter regularly (every 2-3 months) with a high quality filter to reduce dust in your home and allow your heating/cooling system to run more efficiency.
  • Clean Registers: Clean all the registers on your heating/cooling system; and make sure they are not blocked by furniture, carpet, drapes, etc.
  • Programmable Thermostat: Install a programmable thermostat to automatically regulate the temperature in your home during the times when no one is there.
  • Seal Cracks: Seal up any gaps or cracks around windows and doors with weather stripping or caulking to reduce air infiltration into and out of your home.
  • Insulate Attic: Make sure you have adequate insulation in your attic to retain the heat and air conditioning inside your home, which will cause the HVAC unit to run less often.

Good luck with your project,


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Danny Lipford


Danny Lipford is a home improvement expert and television personality who started his remodeling business, Lipford Construction, at the age of 21 in Mobile, Alabama. He gained national recognition as the host of the nationally syndicated television show, Today's Homeowner with Danny Lipford, which started as a small cable show in Mobile. Danny's expertise in home improvement has also led him to be a contributor to popular magazines and websites and the go-to source for advice on everything related to the home. He has made over 200 national television appearances and served as the home improvement expert for CBS's The Early Show and The Weather Channel for over a decade. Danny is also the founder of 3 Echoes Content Studio,, and Checking In With Chelsea, a décor and lifestyle blog.

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