How to Reduce Your Energy Bill with HVAC
Heating and cooling can account for a significant share of the energy used in a home, which means your HVAC system is one of the first places to look when utility bills start climbing.
The good news is that reducing HVAC energy use does not necessarily mean keeping your home colder in winter or warmer in summer. Proper maintenance, smarter thermostat settings, better airflow, and improvements to the home itself can reduce wasted energy while keeping your living space comfortable.
Here are some of the most effective ways to reduce your energy bill with HVAC.
1. Use Your Thermostat More Strategically
One of the easiest ways to reduce heating and cooling costs is to avoid conditioning an empty house to the same temperature you prefer when you are home.
A programmable or smart thermostat can automatically adjust the temperature around your schedule. For example, you can reduce heating while you are away during winter or allow the temperature to rise slightly while nobody is home during summer.
The U.S. Department of Energy notes that using a programmable thermostat appropriately can help homeowners save up to about 10% per year on heating and cooling costs.
Homeowners can find additional practical advice in the U.S. Department of Energy’s home cooling and thermostat guidance.
Avoid dramatic thermostat changes in an attempt to make the house heat or cool faster. Setting your air conditioner to 60°F instead of 72°F, for example, generally does not make it cool the home faster. It simply tells the system to keep running longer.
A Note for Heat Pump Owners
Heat pumps work differently from traditional furnaces and boilers. Large thermostat setbacks can sometimes cause backup resistance heat to operate, depending on the equipment and controls.
If you have a heat pump, your contractor can recommend settings appropriate for your particular system.
2. Check and Replace Your HVAC Filter
A dirty air filter restricts airflow. When your heating or cooling system cannot move air easily, it has to work harder to maintain the desired indoor temperature.
ENERGY STAR recommends checking HVAC filters every month during periods of heavy heating or cooling use and replacing a dirty filter. At minimum, many standard filters should be replaced about every three months, although your equipment and filter manufacturer may specify a different interval.
See the ENERGY STAR guide to efficient heating and cooling for additional homeowner recommendations.
Homes with pets, renovation dust, high HVAC usage, or certain indoor-air-quality concerns may require more frequent filter changes.
3. Schedule Preventive HVAC Maintenance
Small HVAC problems often result in wasted energy long before they cause a complete system failure.
During professional maintenance, an HVAC technician can check components such as:
- Electrical connections
- Refrigerant levels where applicable
- Indoor and outdoor coils
- Condensate drainage
- Blower operation
- Thermostat settings
- System controls
- Burners and heat exchangers on combustion equipment
- Overall airflow and system performance
ENERGY STAR recommends annual pre-season HVAC checkups, ideally before the busiest heating or cooling periods.
Its HVAC maintenance checklist also notes that airflow problems can reduce system efficiency and that dirty coils can make cooling equipment run longer.
Regular maintenance cannot eliminate every repair, but it can help keep equipment operating as designed and identify problems before they become more expensive.
4. Pay Attention to Your Ductwork
If your home uses a forced-air heating or cooling system, the equipment itself is only part of the equation.
Conditioned air still has to travel through the duct system before it reaches your rooms.
According to ENERGY STAR, a typical home’s duct system can lose approximately 20% to 30% of the air moving through it because of leaks, holes, and poorly connected ducts.
Those losses can contribute to:
- Higher utility bills
- Rooms that are difficult to heat or cool
- Uneven temperatures
- Longer HVAC run times
ENERGY STAR reports that properly sealing and insulating ductwork can improve heating and cooling efficiency by as much as 20% in some homes.
Learn more from ENERGY STAR’s duct sealing guidance for homeowners.
Ducts running through attics, crawl spaces, garages, or other unconditioned areas deserve particular attention.
5. Don’t Ignore Air Leaks and Insulation
Sometimes a high HVAC bill isn’t primarily an HVAC problem.
Your system may be operating correctly but compensating for a house that loses conditioned air too quickly.
Common trouble spots include:
- Attics
- Basement rim joists
- Crawl spaces
- Doors
- Windows
- Plumbing and electrical penetrations
- Recessed fixtures
- Poorly insulated walls or ceilings
EPA estimates that homeowners can save an average of approximately 15% on heating and cooling costs by properly air sealing their homes and adding insulation in appropriate areas such as attics, floors over crawl spaces, and basement rim joists.
Homeowners considering these improvements can use ENERGY STAR’s guide to air sealing and insulation as a starting point.
This is particularly important when upgrading HVAC equipment. Installing highly efficient equipment in a house with substantial heat loss may prevent the new system from delivering its full potential.
6. Keep Supply and Return Airflow Clear
Walk through your home and check that supply registers and return-air grilles are not blocked by furniture, rugs, boxes, curtains, or other objects.
Your HVAC system is designed around a certain amount of airflow. Restricting that airflow can affect comfort and system performance.
If some rooms consistently feel significantly warmer or colder than others, don’t automatically close multiple vents to redirect the air. Uneven comfort can indicate duct leakage, inadequate return airflow, balancing problems, insulation deficiencies, or HVAC sizing issues that should be evaluated properly.
7. Use Ceiling Fans Correctly
A ceiling fan does not actually lower the temperature of a room. Instead, moving air across your skin helps you feel cooler.
In summer, set the fan to rotate counterclockwise when viewed from below. This pushes air downward and creates a cooling breeze, which may allow you to raise the thermostat slightly while staying comfortable.
In winter, reverse the fan so it rotates clockwise at a low speed. This helps pull cooler air upward and gently circulate warm air that has collected near the ceiling back into the room without creating a strong draft.
Because ceiling fans cool people rather than empty rooms, turn them off when no one is in the room during summer.
8. Know When Older HVAC Equipment Is Costing You Money
Maintenance can improve the performance of existing equipment, but it cannot turn an outdated system into a modern high-efficiency system.
ENERGY STAR recommends having HVAC equipment evaluated if it is more than about 10 years old or is no longer keeping the home comfortable.
Possible warning signs include:
- Rising energy consumption
- Frequent repairs
- Uneven temperatures
- Excessive cycling
- Unusual noise
- Poor humidity control
- Difficulty maintaining the thermostat setting
If replacement is approaching anyway, compare the operating efficiency of your existing system with current equipment rather than selecting a replacement solely by purchase price.
Modern heat pumps are another option worth considering. The Department of Energy explains that heat pumps transfer heat instead of producing it through combustion and can provide both heating and cooling from the same system. See the Department of Energy’s heat pump guide for an overview of the technology.
9. Start With the Whole House, Not Just the HVAC Unit
If your energy bills seem unusually high, the most productive question may not be:
“What new HVAC system should I buy?”
Instead, ask:
“Where is my home wasting energy?”
A professional home energy assessment can help identify problems such as air leakage, inadequate insulation, duct losses, and inefficient equipment.
Making the right improvements in the right order can sometimes allow a new HVAC system to be smaller and more efficient while delivering better comfort.
Which HVAC Improvements Will Save the Most?
There is no single answer for every home.
A house with badly leaking ducts may benefit significantly from duct sealing. A poorly insulated older house may need weatherization before equipment replacement. Another home may already have a good building envelope but be running an inefficient heating or cooling system that is nearing the end of its service life.
The best approach is to evaluate the entire system rather than focusing on one piece of equipment.
For homeowners in Bourne, Falmouth, Mashpee, Sandwich, and surrounding communities, Upper Cape Heating & Cooling provides installation, repair, and maintenance for heat pumps, air conditioning, furnaces, boilers, and related equipment.
Explore professional HVAC Cape Cod services to determine where your heating and cooling system may be wasting energy and which improvements make sense for your home.