June 21, 2018 Air ConditionersInfo Articles

Why Size Matters When Getting a New Air Conditioner

Cooling your home in the midst of a scorching summer is an essential comfort, but it can also be a costly one. Buying the largest or most expensive air conditioner doesn’t guarantee you’re making the right choice. When it comes to cooling systems, bigger isn’t always better.

When buying a new air conditioner, most homeowners usually go for the right features to meet their comfort needs but rarely do they think about proper sizing and installation.

If you are in search of a new AC unit this summer, make sure you get in touch with an experienced HVAC company in Champlin MN like Marsh Heating and Air Conditioning. That’s because sizing a central air conditioning system is not just matching the size of your existing unit and installation may require some modifications to your home.


Central air conditioning sizing is a process of selecting a unit with the proper level of cooling power for your home. This is not achieved by estimation or guessing. It involves an evaluation of your home’s cooling needs to determine the power of AC needed to condition your indoor environment. This is important because if the AC is not the proper size, problems can occur.

This is how it works: the technician will survey your home and determine its ability to prevent heat from entering and how much heat is trapped inside. This process allows the technician to determine how much air conditioning is needed to overcome it. Factors that are taken into consideration include:

  • The size of the house
  • Type, number, and facing of windows
  • Type and quality of insulation
  • Number of occupants
  • Heat generated from lights and heat sources
  • Your region’s weather conditions

When all these things have been determined, the technician will have a definite idea of what size of air conditioner will provide you with maximum comfort without having to waste energy and shortening the unit’s lifespan.

When an AC is Too Large

Installing an air conditioner that is too large for the house can pose a number of issues including the inability of the unit to properly dehumidify the home and powering on and off too often. This happens when an oversized cooling system will cool the air so quickly that not enough humidified air is allowed to flow over the cooling coil to remove the moisture from the air. Then, the thermostat reaches the set temperature and shuts the AC off, leaving the home over-humidified. Just a short time later, when the temperature rises again, the thermostat will turn the compressor back on — and the process goes on and on. Not only does this issue waste a lot of energy, it also puts too much pressure on the compressor, shortening its life. This will ultimately result in premature damage to the unit, which will require whether a repair or a replacement. The proper way to solve this issue is to install the right sized condensing unit and coils.

When an AC is Too Small

On the other hand, when an air conditioner is too small for the house, it will have a hard time reaching the level of cooling your home needs. When you set the thermostat to your standard comfort level, the unit will need to stay on longer in an attempt to reach it. This translates to the compressor working longer and harder, consuming more power, and shortening its lifespan. This will also result in your home having inconsistencies in cooling, with warm spots in certain rooms where the cooling system is unable to overcome the heat sources such as large appliances and windows facing east or west. The real danger of putting an incorrectly sized air conditioner in your home is quite simple — you’ll have to replace it much sooner than if you installed a properly sized one.

Benefits of a Properly Sized Air Conditioner

A correctly sized AC system can provide the right amount of cooled air into your living space, allowing your family to stay comfortable even during the hottest days of summer.

A properly sized cooling system will cool the home more quickly and easily. Your utility costs will decrease significantly each month, and your maintenance costs will be kept to a minimum.

In addition, a properly sized air conditioner won’t have to run with excessive noise as it will operate according to the manufacturer’s specifications.

Ask the Cooling Pros

If you need help in choosing the right air conditioner for your home, call our experts at Marsh Heating and Air Conditioning. For over 40 years, we have been the preferred Blaine AC installation company and we continue to strive for excellence in providing the best home comfort solutions.