AC Troubleshooting: Home Air Conditioner Starts Cold Then Gets Warm

image of a homeowner feeling hot due to air conditioner blowing warm air

Air conditioners should provide consistency. It should cool your home until the set temperature is reached, and keep it there. If your air conditioner doesn’t work as expected, do a little investigating. For instance, let’s say your home air conditioner starts cold then gets warm. This can be frustrating during the summer when you need your air conditioner to provide relief from the heat. This article discusses some of the causes and solutions for this type of cooling issue.

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AC Troubleshooting: Home Air Conditioner Starts Cold Then Gets Warm

Air conditioners should produce cold air, stopping only when the thermostat setting is achieved. It shouldn’t blow warm air at any point in its cycle. For example, if your system starts with cold air but starts blowing warm air, then this should be indicative of an issue with your unit. Keep reading to explore some of the reasons an air conditioner would do this. For repairs that go beyond changing a filter or adjusting your thermostat setting, be sure to call an HVAC technician from Townsend Energy.

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What Are the Most Common Reasons An Air Conditioner Blows Warm Air?

Here are some of the top causes of an air conditioner blowing warm air:

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Thermostat Settings & Malfunctions

image of a homeowner looking at thermostat due to air conditioner not cooling

The thermostat is an air conditioner’s control center. It senses the home’s environmental conditions and modulates the unit’s activity to maintain the temperature setting. Assuming that the thermostat works properly, check its settings. Also, be sure to check the thermostat’s batteries. The thermostat may also be faulty because of the low battery charge.

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Missing Or Dirty Air Filters

Excess dirt keeps the air from passing through the filters. This places excess stress on the blower and other air conditioner components. It also wears out the system faster while lowering the unit’s efficiency. If there are no filters, it can damage the cooling system because pollutants can get into the cooling system. A thick layer of dirt around the evaporator coils can prevent thermal transfer, lowering the efficiency. It may also result in the unit freezing.

Related Article: Air Conditioner Makes Loud Noise When Starting

Air Filter Maintenance

image of an hvac air filter replacement due to dirty air filter

Air filters need to be maintained consistently. Their effectiveness drops as time passes, so they must be replaced before they become more of a problem than an asset. Replacing the filters is an easy process that most homeowners can do.

How frequently you replace the filter depends on usage and your home environment. A typical family home may need to check the filter once a month. Some homes can change the filters every two months. You may need to conduct a monthly filter replacement if you have a few pets. On the other hand, vacation homes that are seldom occupied may replace the filters once every six months.

Related Article: Portable Dehumidifier Vs. Air Conditioner: Which Is Best?

Low Air Conditioner Refrigerant

The refrigerant is the air conditioner’s life source. It transfers the heat from the indoor air and releases it outside. It travels through the system, cooling your home with every cycle. The air conditioner requires a certain amount of refrigerant to operate properly. A leak can lower the level, causing the system to struggle and operate inefficiently.

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Dirty or Frozen Air Conditioner Evaporator Coils

Evaporator coils catch the heat inside the home. They cannot do their job properly if the coils get too dirty. Indoor air will not be able to heat the refrigerant flowing inside the coils, causing the coils to freeze. It will only worsen unless you do something about it. Clean the coils regularly so this problem doesn’t occur.

Related Article: Why Is HVAC Airflow So Important For My Home?

Dirty or Damaged HVAC Ductwork

image of hvac air ducts

Central air conditioners have blowers that circulate the cold air from the unit to different rooms in a home via the ducts. Damaged ducts mean the cold air will leak. The farthest rooms may not receive cold air anymore. Instead, you will feel hot air coming out of the ductwork. Moreover, damaged ducts can force the system to work harder to reach the set temperature, stressing the system in the process. This causes premature wear and tear, premature AC replacements, and high energy costs.

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Air Conditioner Electrical Problems

Watch out for air conditioner electrical issues. A domino effect can happen if one or more parts aren’t receiving sufficient power. This will then cause warm air to come out of the air conditioner blower.

How To Avoid Unnecessary Issues with Your Air Conditioner

Here are several steps you can avoid unnecessary problems with your air conditioning system:

  • Replace HVAC Filters Frequently: It is essential to have enough airflow for the air conditioner to function properly. Dirty filters are the biggest hindrance to sufficient airflow. Therefore, you should replace the filters as often as needed. Don’t let filters sit on your AC for longer than three months. Replace it once every two months to be on the safe side. If you own pets, change the filters once a month.
  • Schedule Annual Air Conditioner Maintenance: You should do intensive cleaning in your home during spring. It is recommended that you include yearly air conditioner maintenance at this time. This way, your system is better prepared for intense work in the summer. Technicians can determine any emerging problems and resolve them immediately. They will also clean and lubricate the air conditioner so its operations become more efficient and smoother. This helps extend your cooling lifespan, improve home comfort, and reduce energy costs.
  • Be Mindful Of Landscaping Near The  Condenser: Being mindful of debris and dirt helps keep clogs from occurring in your condenser. Trim the plants around it to ensure there is a two-foot perimeter around the outdoor unit. Examine the top and remove any debris as needed. It is common to see dried branches and leaves around it. Remove them by hand or sweep them away.
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Related Article: How Much Clearance Is Necessary Around an Outdoor AC Unit?

What To Do When Your AC Blows Warm Air

Review the list in this article if your air conditioner is blowing warm air. Investigate the likely causes and find the exact issue so you can resolve it using the right solution. Call an HVAC company immediately if the problem persists. This way, the problem doesn’t escalate into bigger ones. Early intervention is also always cheaper than long-term neglect, which can result in a complete HVAC system replacement.

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Air conditioners are built to generate cold air. Act immediately if your home air conditioner starts cold then gets warm. Call a professional HVAC technician to resolve the issue. Immediate intervention can save your cooling unit from breakdowns and protect your wallet from expensive HVAC replacements.

Related Article: Follow These Simple Tips To Improve Your Home’s Indoor Air Quality

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Do not hesitate to contact Townsend Energy for exceptional heating and cooling services in Northeastern Massachusetts, Southern New Hampshire, and Maine. Our professionally certified technicians are experts in superior HVAC replacements, installations, repairs, and maintenance. All our techs are experienced, skilled, and knowledgeable in servicing your HVAC system correctly.

Our company guarantees highly affordable and quality HVAC services in the region. Our team of skilled HVAC professionals can improve your home’s comfort and energy efficiency through our tune-up services. We can also help lower your home cooling bills. We can also suggest the best HVAC repair or replacement solutions for your home and budget. All our work is guaranteed to ensure your satisfaction. Book a service appointment by calling Townsend Energy today. We offer free, in-home estimates.

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