Can You Replace Just The Outside AC Unit?

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The US Department of Energy says that homeowners can depend on their HVAC system for 10-15 years before replacement. Some systems can exceed this timeframe thanks to their quality and maintenance. If you wish to extend the service life of your heating and cooling system, then schedule professional maintenance visits every six months at the minimum. Try to get this done before heading into winter and summer. If your air conditioning system is old, then this is likely to entail a full-system air conditioner replacement. Some homeowners might wonder “Can you replace just the outside AC unit?”.  In this article, we discuss more on this subject.

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Is It Possible To Replace Only The Outside AC Unit?

No. Central air conditioning system replacements work best when done in pairs. If the outside unit is going, then the indoor unit should follow. Homeowners can decide to do otherwise but leaving one behind can result in lower energy efficiency, higher cooling costs, and frequent failures. The following are some of the other reasons why you should always perform replacements in tandem:

Matching Indoor And Outdoor Air Conditioner Coils

The Air Conditioning, Heating, and Refrigeration Institute (AHRI) says that outdoor units will usually need to pair up with specific indoor units. Compatibility is a major issue when you put two random units together. If they do not match, then you will not achieve optimum efficiency. Therefore, replacing the outside unit alone will result in a mismatch that can compromise household cooling. The inefficiency of the pairing will also trigger several issues. Service life will not be as long and the indoor environment will not be as comfortable while the cost of operation will rise.

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Air Conditioner SEER Ratings

image of efficiency vs cost depicting air conditioner with high seer rating

The Seasonal Energy Efficiency Ratio or SEER is a helpful guide in evaluating different HVAC systems. It measures the cooling output of an AC across season against annual energy consumption. This determines the system’s practical efficiency. The Energy Information Administration or EIA says that the minimum standard for the US is SEER 13. The highest possible efficiency can is achievable only when the indoor and outdoor units share equal SEER ratings. A new outside unit is unlikely to match the existing indoor unit’s SEER rating. If you pair them up, then you will have to deal with the issues that come with mismatched systems.


R-22 Refrigerant’s Phaseout

Louder calls for sustainability have prompted HVAC manufacturers to create eco-friendly solutions. They now have greener designs and materials to reduce environmental impact. This is most apparent when looking at the refrigerants used inside air conditioners. Older models contained the substance known as R-22 that is highly effective but harmful to the ozone layer. Federal laws required manufacturers to shift to the much safer R-401A refrigerant. Homeowners who own cooling systems with R-22 should think about upgrading for safety and efficiency. Replacing the outdoor unit alone will not be sufficient since this will result in incompatibilities with the indoor unit.

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Air Conditioner Manufacturer Warranty

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Buyers do not have to worry about new HVAC systems since these come with factory warranties. These will take care of parts and labor if repairs are necessary within the coverage period. Just remember that these warranties may be void if you install mismatched units. You will have to shoulder the repair costs.

Premature Air Conditioner Failure And Repairs

Matching HVAC systems can last 10 or more years with proper maintenance. Meanwhile, mismatched systems tend to fail prematurely because components need to compensate for inefficiencies. They work harder and wear out sooner. Homeowners will have to deal with frequent repairs that cost a lot of money before eventually having to replace the system anyway due to early failure. Prevent this by getting unit replacements in pairs when the time comes to retire the old system.

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The Benefits of Indoor and Outdoor AC Unit Replacement

1. Lower Energy Bills

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The SEER rating will not mean much if you are using mismatched units to cool your home. The energy efficiency of the system will remain low due to the incompatibilities. The units need to compensate by working harder to provide the cooling requirements of the space. This will make energy consumption rise along with energy bills. In contrast, replacing both units together will lower energy bills and result in significant savings.

2. Increased Home Comfort

The higher efficiency of matching indoor and outdoor units will help the system deliver optimum performance. Occupants will notice increased home comfort.

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3. Valid HVAC Warranty

We have already mentioned that manufacturer warranties will only remain valid under certain conditions, including the use of matching units. If you can replace both of these at the same time, then you can enjoy the full coverage on the new system.

Air Conditioner Maintenance Tips

Avoid early cooling system failure and AC replacement by adhering to the following air conditioner maintenance tips:

  • Follow a regular air filter replacement schedule
  • Check the fans to see if they are working as intended
  • Upgrade to a programmable thermostat
  • Have a technician check for clogs and clean the condensate drain
  • Make it a point to use matching indoor and outdoor AC units
  • Use milder temperature settings to lower system load when not in use
  • Conduct periodic HVAC inspections
  • Get annual AC tune-ups in the spring to prepare for summer

There is no guarantee against system failure but you can reduce the risk through diligent maintenance. This will also help the HVAC system serve you longer, perform better, and cost lower to operate. Ensure proper maintenance and repairs by getting an experienced contractor who has the knowledge and skills necessary to take care of your air conditioner.

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We have discussed several advantages of matched AC unit replacement in detail. Keep in mind that pairing units from different manufacturers is not advisable despite similar SEER ratings. This is still a mismatch because the units are likely to diverge in other aspects. Get a qualified contractor to ensure proper matching when you decide to replace your air conditioning units.

Call Miller Oil Company For All of Your HVAC Requirements

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Miller Oil Company provides a wide range of excellent HVAC services in Hartford County, Connecticut. Our team is composed of highly qualified technicians with certifications to prove their skills and competence. They can perform tune-ups, installations, repairs, and replacements. All of them have years of experience and a wealth of knowledge to handle every situation the right way.

Miller Oil Company offers highly competitive rates in the area so there should be no worries about cost. With our maintenance service, you can enjoy greater comfort, lower energy bills, and higher energy efficiency. In case you require system replacement, we can point you to suitable options that match your needs and your budget. Our work comes with a satisfaction guarantee. Schedule an appointment today. We can visit your home and provide free estimates.

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