LG Air Conditioner Not Cooling [Proven Solutions]

If you are looking for solutions to the problem of your LG air conditioner not cooling, look no further. This article is an in-depth look at the possible causes of the problem and common solutions.

LG air conditioner not cooling

LG Air Conditioner Not Cooling – How to Fix

You may want to check the temperature outside and the set temperature of the air conditioner. If the temperature is above 95 degrees Fahrenheit, it will affect the unit’s cooling capacity. Lower the set temperature by a few degrees to see if the cooling increases.

Also, ensure there are no open doors or windows. Every opening through which air can enter from outside must be closed. Otherwise, it will compromise the cooling capacity. For a portable air conditioner, check the vent hose assembly and the window panel to ensure there are no gaps.

Next, examine the duct to see if there are cracks or tears through which warm air is entering the house. Ensure the exhaust duct has no extension; the exhaust fan is too small to blow through the extension, which may cause heat to build up.

Ensure the fresh air vent is not open. The vent allows warm outside air to enter the room through the center of the air conditioner if it is open. As with the portable air conditioner, high external temperatures affect the unit’s cooling capacity. So, lower the unit’s set temperature by a few degrees. Also, ensure you use the Cool operation mode.

Refrigerant Issue

Insufficient refrigerant in the sealed system inhibits the cooling of the air conditioner. It circulates through the system and absorbs the heat from the air flowing over the evaporator coil. Contact LG Support Center for service or get a professional HVAC technician to check the refrigerant and detect leaks in the sealed system if necessary.

Faulty Components

Check the following if you find that your LG air conditioner is not cooling:

1. Filter

It is possible to clean the air filter in an LG air conditioner instead of replacing it every time it gets dirty. But that will mean checking and cleaning it every two weeks or every month. Open the front grille or cover panel if it is a split unit and pull out the filter. A portable air conditioner usually has more than one filter; some have two while others have four.

Put the filter in a container or sink and wash it with warm water and mild soap. Never wash a filter with a harsh cleaning agent or chemical as it may damage the manufacturing material. After washing it, dry it with a lint-free cloth before leaving it out to dry completely. Finally, place it back into the air conditioner.

A dirty filter restricts airflow through the air conditioner, no matter the type. Dirt acts as a blanket that prevents cold air from flowing out, trapping it within the unit. Not only does it restrict airflow, but it also causes the evaporator coil to freeze due to the trapped cold air. Over time, the air conditioner will begin to malfunction and eventually fail.

2. Condenser Coil

It may not be so easy to clean the condenser coil of an air conditioner, especially if you have never done it. It will require opening the outside unit and locating the coil. Next, use a brush or vacuum with an attachment to remove leaves, dust, and other debris from the fins.

If the coil needs a deeper cleaning, use a garden hose to wash the dirt off of the fins. Do not use force; ensure the flow of water is gentle. And when you are done cleaning, allow the fins to air-dry before using the unit. Work gently around the fins to avoid damaging them.

The condenser is a vital part of the air conditioning unit. It dissipates the heat that the refrigerant absorbs from the air to prevent overheating in the unit. The fan keeps the coil and compressor cool. But if the condenser is dirty, it cannot efficiently dissipate heat because the dirt acts as insulation, keeping the heat trapped. Eventually, the air conditioner will stop cooling.

3. Evaporator Coil

The coil may be frozen due to a dirty filter or a lack of refrigerant. Turn off the air conditioner and wait until the coil thaws from the ice before turning it back on. Check the filter to ensure it is not dirty. If it is no longer usable, replace the filter. Then, use the services of a technician to determine the amount of refrigerant in the system to prevent the coil from freezing again.

4. Thermostat

Ensure the air conditioner is powered on. Next, set it to Cool and locate the thermostat. Using a multimeter, test the component to check for continuity. Replace the thermostat if you do not find continuity, even as the air conditioner is still in the cooling mode.

A thermostat in good working condition typically monitors the air temperature. When the temperature rises beyond a preset point, the thermostat powers the selector switch to send power to the compressor and fan. So, the air conditioner may not cool as it should if the thermostat becomes faulty as it may not be able to send power to the cooling system.

5. Temperature Control Thermostat

Like the thermostat, the temperature control thermostat must be in good working condition to help the air conditioner cool. Using a multimeter, run a continuity test on the thermostat. If it shows no continuity, it needs a replacement.

This thermostat works as a sensor to detect the temperature and power the cooling system when the temperature becomes warm. The cooling system, which comprises the compressor and fans, may not run if the temperature control thermostat fails.

Note: Both types of thermostats may have more than two terminals if the air conditioner has a heating function. In such a case, refer to the unit’s wiring diagram for more information on how to test the thermostats.

6. Thermistor

First, check the user manual for the air conditioner to know the exact resistance and temperature values for the unit. Next, locate the thermistor, which is a sensor likely fixed to the control board. Check it for continuity or resistance using the values you earlier checked. If the resistance does not correspond to the values, replace the thermistor.

The sensor keeps an eye on the air temperature to detect a rise. If the temperature rises, the sensor signals the control board to power the cooling system. But if the sensor is defective, the cooling system may not run and the air conditioner will not produce cool air.

7. Compressor

The compressor of an air conditioner hardly fails but if it does, one of the signs is that the unit will stop running. However, check other components for defects before settling on the compressor because it is usually an expensive fix. You may also need a technician to help you test the compressor and recommend a permanent solution.

8. Capacitor

The run capacitor of the compressor may be faulty. If it is faulty, the compressor cannot run at all. You will need to run a continuity test on the capacitor using a multimeter. If the capacitor shows no continuity, replace it. Otherwise, the compressor will keep the air conditioner from cooling.

9. Boards

If the main control board or temperature control board stops working, the air conditioner cannot produce cool air. Therefore, check the boards’ functionality, but only if other components more likely to fail are working well. And if the boards are not working, replace them.

This process may be a little tedious so it may help to use the services of a technician to troubleshoot the air conditioner and find the exact cause of the cooling problem.

Perform a Reset

Consider resetting the air conditioner to see if it fixes the cooling problem. Many times, a simple reset takes care of minor errors and faults. Press the power button of the unit and disconnect the air conditioner from the wall outlet. 

Wait at least ten seconds before reconnecting it to the outlet and turning the unit on again. Set the mode of operation to Cool and adjust the temperature to the lowest point. Also, increase the fan speed to the highest point. Then, wait a few minutes to see if the unit starts cooling.

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LG Air Conditioner Not Cool Enough – Quick Fix

The problem may stem from low refrigerant or closed vents. If the refrigerant is low, the air conditioner may release cold air but not enough of it. Hire a certified technician to check the refrigerant level and add more if necessary.

Check the vents to ensure there is no obstruction, especially window units. Clean the vents and remove debris that may be clinging to them. Also, check the size of the unit to ensure it corresponds to the size of the room.

Air conditioners have British Thermal Units (BTUs) ratings that instruct you on which size suits your house. The capacity is measured to match different room sizes, so you must buy your LG air conditioner with the size of the space where you want it in mind.

If you have an LG air conditioner that is smaller than the space where you install it, it will not be able to cool enough. You may have to exchange your current air conditioning unit with a more suitably sized one for your home or workplace.

Outside temperature plays a vital role in how cool your air conditioner is, especially if it is a small unit. If the temperature is excessively high, the air conditioner will not cool well enough. Try lowering the set temperature and ensuring all openings are closed. And use the highest fan speed after setting the unit to Cool.

How to Set an LG Air Conditioner to Cool

Setting an LG air conditioner to the Cool mode of operation is straightforward. The air conditioner must be running and if it is, use the temperature buttons, which are the buttons with the up and down arrows, to set the temperature you desire. After that, use the Mode button to select the Cool mode. This article explains how to activate each mode and what they do in detail.


If you find your LG air conditioner not cooling, it is crucial to find out the source of the problem and fix it. Check the air temperature, set temperature, and openings. These affect the cooling capacity of an air conditioner more than faulty components. Therefore, check them first before the components.

If the temperatures and openings are not the cause, troubleshoot the air conditioner components to find faulty ones. Possible causes are a dirty air filter, dusty condenser coil, frozen evaporator coil, low refrigerant level, damaged compressor, malfunctioning control boards, defective thermostats, and faulty thermistor and capacitor.

Most of these parts are easy to repair or replace. But parts such as the compressor needs a certified technician to fix. The same applies to recharging the system with refrigerant. The problem may also stem from the unit being too small for the space.

Fortunately, this article takes a detailed look at each possible problem and common solution. Use it as a guide to fix your unit. Remember that regular maintenance prevents such problems, so service the unit every month or once every three months.

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