Why Does Air Conditioner Sizing Matter?

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Summer pushes your cooling system to its limitations. Unfortunately, an old, outdated air conditioner won’t be able to handle the heat. You’ll notice that it breaks down frequently. At this point, you’re faced with the inevitable air conditioner replacement.

When choosing a new unit for your home, make your decision wisely. For example, some homeowners make the mistake of getting the same model they had before. However, this may not be the best option for them. Others may even be drawn to invest in the biggest air conditioner available, thinking it may cool their home faster. Regardless, don’t buy a new unit impulsively. Consider several factors first. For example, air conditioning sizing should be considered for any new installation. 

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What Is A Manual J Load Calculation & Why Is It Important?

The Manual J load calculation is a complicated process factoring in several influences on your home’s cooling needs. Licensed HVAC technicians should calculate this cooling load because they understand the intricacies needed to complete it. They may use advanced software to help speed up the process while ensuring its precision. They quantify house specifications like:

  • floor area
  • orientation
  • ceiling height
  • window sizes
  • structure materials
  • insulation
  • air leaks
  • heat production of appliances,
  • number of occupants
  • and more

The result of this calculation is your home’s cooling load. You don’t have to guess when you know this numerical value as you know the exact air conditioner size you need. 

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Cooling Comfort

image of a homeowner feeling comfortable due to proper air conditioner size

Air conditioning systems are designed to provide comfort. They do this by cooling the air as well as lowering the humidity via condensation. Vapor on the coils can turn into water droplets running down it.

Having an air conditioner that’s too large means it cools your home faster, and the cycle ends before sufficient condensation and humidity reduction happen. As a result, the occupants will feel sticky and uncomfortable from the continued high humidity. Typically, they’ll try to lower the thermostat setting to get more relief, but this only cools the house and spikes the energy consumption. The home will still have high levels of humidity. Shorter cycles from a unit that’s too large also reduce the air quality inside your home. The system pushes less air into the filters, compromising the cleaning process.

It is also problematic to have a unit that’s too small because it may not be able to handle the home’s cooling demands. It will take a long period to achieve the set temperature. It may have trouble countering the sun’s warmth radiating from the roof during scorching summer days. They will overwork but still fall short of reaching the target temperature. Air conditioners that are too small also work constantly, leading to faster wear and tear. This will then result in frequent breakdowns and premature replacements.

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Air Conditioner Efficiency

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Selecting a model with a high SEER rating is one of the best methods to ensure the unit can convert electrical energy into cooling power effectively. However, homeowners should also consider other factors that impact efficiency, such as air conditioner sizing. A mismatched unit cannot achieve its potential SEER rating and instead will run sub-optimally. This means it will experience significantly prolonged or shortened cycles, wasting tremendous amounts of energy. The unit also won’t run as efficiently because of increased wear and tear. Therefore, there is no use in purchasing a new air conditioner with a high SEER rating if it isn’t sized correctly.

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Air Conditioner Cost

Mismatched units will cost you more from the onset as you must spend more than you should on your air conditioner. Much like cars, the price increases with higher horsepower. Therefore, you should consider your cooling needs carefully before deciding which unit to buy. A cooling system that cycles frequently wastes energy and wears out the components faster. This translates to reduced system efficiency, spiking up your monthly energy bills. Extreme stress on the AC components may result in frequent repairs and premature replacement. Ensure the unit is properly sized from the start to avoid unnecessary expenses. Hiring a licensed professional for a Manual J calculation is a worthy investment.

Related Article: How Much Clearance Is Necessary Around an Outdoor AC Unit?

The Problem With Oversized Air Conditioning Units

homeowner suffering from high humidity at home due to air conditioner problems

Units that are too large can cause a myriad of problems because they cool the area too fast and cause short cycles. This issue keeps the air conditioner from effectively reducing the humidity inside your home and improving indoor air quality using filters. The units also operate sub-optimally, which increases energy usage. All these problems can result in your home feeling cold but humid. Homeowners may also overspend to purchase the unit.

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The Problem With Undersized AC Units

Units that are too small are as problematic because they cannot provide adequate cooling power to reach the requirements of a space. These units are incapable of bringing relief in the hottest months of the year, so having them in your home is quite questionable. They will run constantly because they keep trying and failing to achieve the set temperature. The parts of the unit will be constantly stressed, leading to equipment failures and expensive early replacement. 

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Choosing an air conditioner isn’t a race to the extreme. Getting the smallest or largest unit doesn’t guarantee the best possible results. It may be easy to make assumptions, but each home has varying needs. The correct air conditioner unit should meet your home’s unique requirements. Remember that sizing is crucial in air conditioner selection because it determines cost, efficiency, and comfort. Don’t utilize general rules when choosing the most suitable AC size for your home. You should hire a licensed technician who will scientifically calculate the exact air conditioner size your home needs.

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Call R.F. Ohl For Your Air Conditioning Requirements

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R.F. Ohl is the leading provider of excellent HVAC services in Northeastern Pennsylvania, including the Poconos and the Greater Lehigh Valley Region. We have the best professionally certified technicians for all your heating and cooling service needs, including mini-split replacements, boiler maintenance, furnace repairs, air conditioner installation, and many more. Our friendly techs have extensive experience, knowledge, and skills to service your HVAC system correctly.

We guarantee to have the region’s most competitive HVAC service prices. Our tune-up services can increase your home’s energy efficiency and comfort while lowering your cooling expenses. We can recommend the best, budget-friendly air conditioner replacement system if you need one. Book a service appointment with R.F. Ohl today. All our work is guaranteed because we prioritize client satisfaction. Call now for a free, in-home estimate.

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