As convenient as an air conditioner is, sometimes, it does not produce the cool air you need. Learn how to fix Carrier air conditioner blowing issues in this article.

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Carrier Air Conditioner Blowing Warm Air – How to Fix
Several faults can cause a Carrier air conditioner to blow warm air, and you may be able to fix them yourself.
1. Dirty Air Filter
One of the primary reasons your Carrier air conditioner is blowing warm air is a dirty air filter. The filter is usually inside the indoor unit, but you can use the owner’s manual to check the exact location, especially if you have a central air conditioning system. This article on how to clean a Carrier air conditioner filter has instructions to guide you in cleaning yours when you remove it from the unit.
However, you may need to replace it if it is older than two months. Never use an air filter in an air conditioner for longer than the manufacturer’s recommendation for the best air quality. You can also opt to switch to a higher quality filter, especially one with a high MERV rating. A filter with an 11 MERV rating will trap more airborne particles and make the air cleaner than one with a 5 MERV rating.
2. Wrong Thermostat Setting
The thermostat acts as the control panel for the air conditioner. You can adjust the mode of operation, the fan speed, and the temperature setting for the air conditioner through the thermostat. So, if the air filter is in good condition, but the air conditioning system is blowing warm air, check the settings on the thermostat.
If you want the system to blow cool air, set the mode of operation to Cool and ensure the fan is set to Auto. You can opt to set the mode of operation to Auto, but that means the cooling function runs automatically and may shut off and on at intervals.
Setting it to Cool ensures the system constantly produces cool air. The fan must run on Auto so the air conditioner can control its functionality with the cooling system. If you set it to On, it typically circulates the air in the room without cooling it. Consequently, it warms the air instead of cooling it.
You may have a defective thermostat. If you are sure nobody is tampering with the customized settings but the settings keep changing, the thermostat may have loose wiring or connections or is failing. Consider replacing the batteries in the thermostat if it is battery-controlled or fixing other faults. Use professional help for this task.
3. Sealed System Leak
Refrigerant is a gas that flows through the sealed system of an air conditioner, acting as a coolant. The same is true for refrigerators. Typically, the gas recycles, so there is usually no need to recharge it.
However, if the sealed system leaks, the gas escapes and reduces the system’s cooling capacity. You may notice residue around the refrigerant tubes around the outdoor unit. The evaporator coil in the indoor unit may also leak. But if the outdoor unit leaks refrigerant, it may be difficult to detect a leak unless you see residue.
You are more likely to smell the gas if the indoor unit leaks refrigerant. In such a situation, open doors and windows to provide cross ventilation. Turn off the air conditioner and call for professional help; contact the Carrier Service Center or use the services of an independent HVAC technician.
4. Damaged Return Duct
Air conditioning systems usually have return ducts through which air enters, gets cooled, passes through the filter, and blows into the room. If the ductwork is damaged, the system will lose air, resulting in reduced airflow. Even if the air is cooled, it won’t be enough to cool the room eventually. As a result, the space remains warm.
Check the ductwork if nothing else seems to be causing the air conditioner to blow warm air. You will need professional help to inspect it because the ductwork runs in the walls, especially for central air conditioning systems.
5. Dusty Condenser Coil
The condenser coil transfers heat out of the system. When the refrigerant circulates through the system, it absorbs heat from the air and leaves it cold. The refrigerant travels back to the condenser coil, and the heat is expelled from there. However, dirt acts as insulation to keep the heat from leaving the system, causing the temperature to rise and compromise the cooling capacity.
Therefore, cleaning the condenser coil and other components in the condensing unit is crucial. You may not have to clean it regularly; once or twice a year is enough. But over time, the coil will need cleaning. Follow this guide to clean the condenser and evaporator coils in your Carrier air conditioner. If you are unsure about cleaning the coil without damaging the fins, contact Carrier and request immediate service.
6. Frozen Evaporator Coil
Split air conditioning systems typically have the evaporator coil in the indoor unit or air handler. But if the indoor unit functions as a furnace, the evaporator coil is located where the air flows out. And if the coil is a fan coil, you will find it in the cabinet for the fan coil.
Locate the coil for your specific unit and check whether or not it is frozen. A dirty air filter is one of the causes of a frozen evaporator coil; dirt blankets the coil and traps the cold air in it. Over time, the coil begins to freeze and continues to do so as long as the dirt remains.
Other possible causes of a frozen coil are a low refrigerant level, dirt and pollutants on the coil, and even excessive dirt on the condensing unit. Thaw the coil using a hairdryer or leave the air conditioner off for some time until the ice melts. Ensure you find out why ice accumulated on it to prevent a future occurrence. Otherwise, the coil may become damaged, and you will have to replace the entire air conditioning system.
Some of the troubleshooting steps above are easy for a DIYer. So, save yourself money and time by performing those within your skillset. However, if you have to deal with electrical connections or refrigerant, disconnect the air conditioner from electric power and hire a professional HVAC technician for further assistance.
Carrier Air Conditioner Not Blowing Hot Air – Quick Fix
If you find your Carrier air conditioner/heater is not blowing hot or warm air, ensure you select the heating function and the furnace is operating. Check the thermostat settings for the conditioner and the air filter. Also, check the reversing valve and the condensing unit outside the house. Furthermore, the air duct may be leaking, or the system has insufficient refrigerant. Check out this article on a Carrier air conditioner not heating for troubleshooting and repair steps.
In addition to the above, ensure the return vents and supply vents. The air conditioner must first take air into the system, process it, and supply warm air to the room. If any vent is closed, partially or entirely, it restricts the airflow and may cause irreparable damage to the air conditioner over time. But if the vents are fully open and there is no hot air, there may be a problem with the ventilation system, particularly the ductwork.
Check out these other articles…
Carrier Air Conditioner Not Working [Proven Solutions]
Carrier Air Conditioner Lock [Issues & Solutions]
How to Reset a Carrier Air Conditioner [Detailed Guide]
Carrier Air Conditioner Thermostat [Detailed Guide]
Carrier Air Conditioner Timer [Issues Solved]
Carrier Air Conditioner Blowing Issues: System Not Blowing – Fixed
The primary reason a Carrier air conditioner does not blow is a lack of electric power. The first thing to check is whether or not it is coming on at all. If you power the unit and it does not beep or respond in any way, check the breaker that controls it. Ensure it is on, especially if there is a recent power outage.
The breaker is usually outside the house. Some fuses operate with it, and the air conditioner will not work if one fuse is blown. You may need the help of an electrician to determine if the breaker is faulty. But if it seems to be in good working condition, reset it and power the air conditioner.
Another part to check is the power switch. Some systems have dedicated switches that power the indoor units. If the switch is off, turn it on and see if the air handler responds. Also, check the disconnect box next to the outdoor condensing unit. It should be set to On, not Off. Turn it on and wait for the condenser to respond. However, get professional assistance if the air conditioner still does not blow.
Sometimes, the air conditioner may be off. Check the thermostat and ensure the system is on. Also, check the electric connection points for proper functionality. The air conditioner must be on a dedicated circuit because of its voltage needs. In other words, it may not work at all if it shares a circuit with other appliances. An HVAC technician or an electrician is in the best position to determine why the air conditioner is not blowing.
Recap
Some Carrier air conditioner blowing issues are easy to fix yourself. All you need is to troubleshoot correctly. This article has detailed instructions on how to troubleshoot components that may cause the system to stop blowing cold or warm air or no air. Then, you can follow the repair steps to complete the task.
Regularly clean and run maintenance checks on your Carrier air conditioner, especially on the condensing unit. Also, keep the filter clean and replace it when due. Follow the manufacturer’s directions to clean and maintain the coils to prevent damage and eventual refrigerant leak. Contact Carrier for service if the blowing issues continue. Alternatively, find a professional HVAC technician for service and further assistance.