Is your HVAC system keeping your home comfortable? If you've noticed fluctuating temperatures, changes in your energy bills, or new and unexpected noises, you might side-eye it, questioning whether it was always like that, or if it's due for maintenance or — gulp — time to upgrade.
For many homeowners, the HVAC system is a significant investment. Despite all the technological advancements, determining whether your unit is still efficient isn't always easy. But you can't ignore changes in its operation, either. Ignoring potential issues can compromise your home's comfort and lead to high repair bills and increased energy costs in the long run.
Understanding the energy efficiency of your HVAC system is important, so we connected with David Richardson of the National Comfort Institute, a recent guest of "Sustainability Series" with HGTV's Dave Marrs, a program sponsored by Daikin. Before you hire a technician, use these tests to check for these telltale signs of an inefficient HVAC unit.
Test #1: Use Toilet Paper
Airflow is a major indicator of home comfort and can help you understand what air quality, or energy losses occur within your spaces. A simple visual demonstration using toilet paper can help you see which way air is moving, and whether it's flowing into or out of a room.
"Get three sheets of single-ply toilet paper and hold it at the edge of the door as it's closed," shares Richardson. "Slowly open the door and see which direction the toilet paper goes. If it pulls into the room that shows either the room is in a vacuum or the area outside that room is positively pressurized. If the paper sticks to the door it shows that the room is positively pressurized or the area on the opposite side of the door is in a vacuum or negative pressure."
Why is this important? As he explains, "Any issues such as dust, uncontrollable humidity, uncontrollable temperature differences, and drafts are usually the result of rooms that fail the toilet paper test. As with any test, it's best to use measurements with precision test instruments to quantify what you see."
Test #2: Inspect for Duct Leakage
What does a duct inspection do? "It helps us see if all the conditioned air that a heating and cooling system produces makes it to the proper locations," explains Richardson "Just as you wouldn't want water leaking out of plumbing pipes, you don't want air leaking out of your ductwork." Unlike a dripping pipe, a leaky duct can go unnoticed for longer because drafts aren't visible to the naked eye. Duct leaks drastically affect the comfort, humidity control, energy use, and air quality of a home. Until air leaks are corrected, even a brand-new HVAC system may not operate to its full potential and could fail prematurely.
Richardson elaborates on how to check your system. "Look at your duct joints to see if they have any form of acceptable sealant on them. One type is a product called mastic which creates a seal between duct connections to keep air inside of them, similar to the solder on water pipes. If you only see bare duct connections with no type of sealant, there's a good possibility air is leaking from your duct system."
#3 Check for Effective Insulation
An efficient unit relies on surrounding insulation to help retain an indoor temperature and prevent the transfer of outdoor temperatures. Whether you're using a central air conditioner or heating your home during chilly winter nights, insulation matters.
"This step helps you see if there are any insulation gaps or hidden areas behind drywall that could allow excessive heat transfer between spaces that are connected to the outdoors such as an attic, crawl spaces, or garages," notes Richardson. "You'll need a thermal image camera, which is a high-precision test instrument that allows you to see the temperature of different surfaces. You can compare how hot and cold these surfaces are to the temperature on the thermostat. Ideally, all the surface temperatures should be very close to the temperature on the thermostat."
He adds, "Hidden sources of heat gain and loss often cause HVAC systems to operate poorly. They also result in hot and cold spots that are often blamed on the HVAC system when they are in reality a building problem. A home should function just like a cooler that can manage temperature fluctuations inside.
What are SEER ratings, and why do they matter for energy efficiency?
SEER, or Seasonal Energy Efficiency Ratio, measures how efficiently an HVAC system operates across an entire season, looking at hot summer days as well as the coldest winter days.
- A higher SEER rating indicates that the system uses less electrical energy to provide the same heat output. This means a homeowner can reduce energy consumption and lower utility bills.
- For modern, energy-efficient HVAC units, a SEER rating of 16 or higher is ideal. It's especially helpful if you use features like programmable thermostats or smart thermostats.
Systems that qualify as Energy Star-certified meet high standards for efficiency, making them excellent choices for homes aiming to save on energy costs while reducing environmental impact.
What’s considered a good energy efficiency rating for HVAC systems?
A good energy efficiency rating means that an HVAC system runs at peak efficiency with minimal energy waste. Energy Star-rated units typically signify top-tier cooling and heating efficiency, which can be important if you're looking to cut down on your primary source of energy consumption.
Systems like high-efficiency heat pumps, which perform well even in colder climates, are great options for efficient heating and cooling.
Additionally, routine maintenance plays a role in maintaining these efficiency levels; for example, regular maintenance on oil furnaces helps sustain energy efficiency and extend equipment life. A programmable thermostat can further optimize your HVAC efficiency by adjusting temperatures based on your schedule.
