AC Maintenance: Does Closing Your HVAC Registers Really Save Energy

Homeowners commonly try to save money on their utility bills by closing vents and shutting doors to unused or little-used rooms. If this space accounts for 10% of the total square footage, the misconception is that denying heat or air conditioning into the space will require less than 10% less energy. Whole-house mechanics work against this for several reasons. We will show you why and a way that you might accomplish these 10% energy savings.

• Closing the door and the supply vents is only half of the ventilation process. Return vents are also pulling air from the house back through the HVAC system. The return air vent is creating negative pressure in the closed-off room. The negative pressure will pull air from the outside, air infiltration, and make the room hotter or colder than the rest of the house. This will not help you save energy.
• Closing the vents increases the air pressure in the ductwork that services the closed-off space. Air is pushed into the duct with no outlet. Since the ducts are fabricated from pieces of sheet metal, connected, and sealed with tape or mastic, any gap or opening will be amplified by the increased pressure. Normal air pressure commonly bypasses these imperfections and leak very little air, since the air is pushed into an open room.
• Closing the vents also creates positive pressure, pushing back against the blower motor, since it was sized to push air into the entire house. This causes the blower motor to work harder than it should and this wastes energy.
• Your HVAC system was customized to fit your house—not too big, not too small, but just right. Reducing the square footage it serves can result in “short cycles.” This reduces the energy efficiency of the system and can increase indoor humidity in the summer months.

Closing a space of your HVAC system will not give you the energy savings you seek. So what will make a difference in your utility bill? Try these two solutions.

Learn to use a programmable thermostat. The thermostat is the control switch for the HVAC system. Schedule temperature changes of 7⁰ to 10⁰ during both heating and cooling season for at least eight hours. These temperature changes can be scheduled overnight, during sleeping hours, and/or during the day, while the family is away at work or school. According to the Department of Energy, this measure can save 10% on your utility bill each month.¹

Regularly scheduled AC maintenance is one of the most commonly overlooked steps in managing your utility consumption. Our technicians thoroughly inspect your AC system components to ensure they are in proper working order. In addition, a key component to AC Maintenance is changing your filter regularly.

Questions About AC Maintenance?

Our four decades of experience as an Air Conditioning contractor, AirPro Houston provides you with the skill and expertise to answer your AC Maintenance questions.

We have several financing options available with great options with up to 72-month terms with approved credit. Call us today at  281-880-8805 and let us partner with you for all of your AC maintenance, repair, and installation needs.

¹ https://www.energy.gov/energysaver/thermostats#:~:text=Thermostat%20Operation&text=You%20can%20easily%20save%20energy,asleep%20or%20away%20from%20home.&text=In%20fact%2C%20as%20soon%20as,the%20surrounding%20environment%20more%20slowly