Prioritizing Your Appliances

2 Air Conditioning No-No's That Could Damage Your System

During the summer months, you might do everything you can to cut down your power bill. In addition to carefully changing your air conditioning filters and programming your thermostat, you might also focus on shading your air conditioner and closing unused vents. Unfortunately, some of your efforts might do more harm than good. Here are two air conditioning no-no's that might be damaging your system:

1: Closing Vents You Don't Think You Need

Since you don't spend a ton of time in that office or walk-in closet, you might not think twice before snapping those vents closed. After all, if you can limit airflow in unused areas, wouldn't more cooled air make its way to common living areas? Although it might seem like simple logic, closing air vents can cause these problems:

  • Added Ductwork Pressure: When you close air vents, it increases air pressure inside of your ductwork. Although you might assume that this added pressure would send a burst of cooled air to your kitchen or living room, the fact of the matter is too much pressure can harm your system. When internal duct pressure increases, leaks can occur along joints and seams, sending climate controlled air into empty wall or ceiling voids.  
  • Interferes with Air Returns: Closing vents also increases the air pressure inside of unused rooms, which can interfere with how air is pulled through your system. For example, if your air return is located in a room where all of the air vents are closed, it might send hot air back through your system continuously, which might cause your air conditioner to stay on longer than it should.   
  • System Failures: When vents are closed, it also makes it harder for your air conditioner to push cooled air throughout your home, which can strain your system. After awhile, you might experience wear and tear, such as compressor problems or fan failures.

To avoid problems, leave all of the vents in your home open so that your air conditioner can regulate itself. If you are concerned about some rooms being colder or warmer than others, hire a professional HVAC technician to see if your system is balanced (you can find an HVAC company at a site like They will be able to perform an efficiency audit to see if vents need to be added, moved, or permanently sealed off.

2: Letting Your Landscaping Run Wild

Since shading your air conditioner can improve efficiency by as much as 10%, some folks are tempted to let their landscaping run wild. Instead of carefully pruning trees and shrubs, you might ignore your plants and assume that they are helping your air conditioner. Unfortunately, letting your landscaping run wild can cause these issues:

  • Shrubs: That shrub might seem like an easy way to cover up that unsightly air conditioning unit, but it might also be impeding airflow—which can strain your system.
  • Ivy: In addition to limiting airflow, ivy can actually make its way inside your unit and interfere with internal components. Also, since vines give pests easy access into warm, enclosed spaces, they can pave the way for rodents to damage wiring or make their way indoors.
  • Mulch: To make your landscaping look clean and tidy, you might be tempted to pile mulch around your air conditioner and adjacent plants. Unfortunately, if mulch is kicked into your air conditioner by a passing pet or lawn mower, those bark chips can get tossed around inside your unit—damaging fan blades and denting your compressor.  

If you want to keep your air conditioner damage-free, keep plants at least two to three feet away from the sides of your unit, and provide at least five feet of clearance around the top of your system.  

By knowing how to avoid common HVAC mistakes, you might be able to reduce repairs and keep your home comfortable.