How To Tell When You Have An Oversized Or Undersized HVAC System

If you're wondering why you're having a tough time staying cool and comfortable in your home, it could have a lot to do with your HVAC system. There's a good chance that your HVAC system may be too large or too small for your home, resulting in a broad range of comfort and efficiency issues. Here are a few ways you can tell whether you have an undersized or oversized HVAC system installed in your home.

Oversized HVAC System Symptoms

Contractors and technicians going by the "rule of thumb" often install HVAC systems that end up being oversized in comparison to your home's cooling needs. Some homeowners deliberately purchase oversized HVAC systems under the mistaken belief that a bigger system offers better cooling. If you think you have an oversized HVAC system in your home, here are a few symptoms to look out for:

  • Short run times - A typical HVAC system takes 7 to 10 minutes of continuous operation to reach its maximum efficiency. An oversized HVAC system may run for less than 7 minutes.
  • Short cycling - Oversized HVAC systems can actually cool too quickly, causing the unit to cycle on and off within a short window of time. This can cause wear and tear on the HVAC system.  
  • Excess moisture - Oversized HVAC units often don't have enough time to properly dehumidify the air, resulting in excess moisture that often leaves indoor spaces feeling clammy and uncomfortable.
  • Mold growth - Mold growth in the HVAC system and elsewhere in the home is often a symptom of an oversized HVAC system.
  • Higher utility bills - Operating an oversized HVAC system could result in higher-than-average energy costs.
  • Frost/ice problems - Excess moisture caused by an oversized HVAC system could lead to frost or ice formation on the evaporator and/or condenser coils.

Undersized HVAC System Symptoms

Undersized HVAC systems can be just as problematic as their oversized counterparts. Some contractors and even quite a few homeowners purposely install undersized HVAC systems in an effort to improve energy efficiency and save costs in the process. Here are a few signs to watch for when it comes to undersized HVAC systems:

  • Excessive run times - If you've noticed your HVAC system has to run continuously for hours on end just to keep your home cool, you may be dealing with an HVAC system that's too small for your home's cooling needs.
  • Increased HVAC wear and tear - Excessively long run times can also cause increased wear and tear on various HVAC system components, resulting in higher repair bills and longer downtime.
  • Higher utility bills - Running an undersized HVAC system constantly can also lead to higher energy costs.
  • Poor comfort - If you can't seem to cool off certain parts of your home using your HVAC system, there's a good chance it may be too small for your home.

What You Can Do About It

The best way to deal with an undersized or oversized HVAC system is to have an experienced HVAC technician or contractor reevaluate your home's heating and cooling needs using the proper tools and techniques. Instead of using the rule of thumb, your technician or contractor should use the Manual J load calculation process to accurately assess your home's cooling needs.

Once this task is complete, a technician or contractor from a company like Cape Fear Air Conditioning & Heating Co., Inc. can help you choose the right HVAC system that accurately addresses your home's heating and cooling demands. Replacing your current oversized or undersized HVAC system with a newer, more efficient and properly sized unit can be a great opportunity for your home if your current system is over 10 years old.

About Me

cool and hot areas of the home

I live in an older home that we are working to renovate. There are three areas of the house that just don't seem to get cool in the summer or get warm in the winter. I have done all that I can to try to keep these areas comfortable, but I wasn't able to do much until I hired an HVAC technician to come out and figure out why those areas were so uncomfortable. This blog will show you what can be causing areas of your home to be less comfortable than other areas when it comes to temperature during both winter and summer.