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HomeRepair HelpLennox A/C RepairLennox Air conditioner - home's humidity is too high Repair
Lennox Air conditioner - home's humidity is too high
If your Lennox air conditioner is not removing humidity, start with airflow. A clogged air filter is the most likely reason for home humidity too high because restricted airflow reduces cooling capacity and can let the evaporator coil frost over, which keeps the system from pulling moisture out of the air. Clean the filter if it is washable, or replace it if it is damaged or packed with debris. Next, check the condenser coils. Dirty condenser coils cannot release heat efficiently, so the AC may run longer, cool poorly, and still leave the air feeling damp. If airflow and coils are in good shape, the problem may be a temperature control thermostat that shuts the unit off too soon, a faulty thermistor sending bad temperature readings to the control board, or a sealed system leak or restriction that requires a qualified technician. When your Lennox AC is not dehumidifying or the air conditioner is not removing moisture properly, enter your model number on RepairClinic.com to find the exact air filter, thermostat, thermistor, or other replacement part for your specific air conditioner.
01 - Clogged Air Filter
If the air filter is clogged, air cannot flow properly through the air conditioner. This greatly reduces the cooling capacity of the air conditioner. In addition, if the air filter is clogged, the evaporator coils will frost over and not be able to remove moisture from the air. To remove debris from the air filter, try cleaning the filter. If it is not possible to clean the air filter, replace it. Refer to owner's manual for guidance.
Top Solution
02 - Lennox Air Conditioner Air Filter
If the air filter is clogged, air cannot flow properly through the air conditioner. This greatly reduces the cooling capacity of the air conditioner and cause higher humidity in the home. In addition, if the air filter is clogged, the evaporator coils will frost over. Most air filters used in stand-alone air conditioners can be cleaned with soap and water. Only filters that are extremely clogged with debris or damaged will need to be replaced.
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Highly Likely
03 - Condenser Coils are Dirty
The condenser coils dissipate the heat as the refrigerant passes through the coils. If the condenser coils are dirty, they won’t be able to dissipate the heat as effectively. As debris builds up on the coils, the air conditioner will become less efficient, causing the air conditioner to work harder to cool down. If the coils are significantly dirty, the air conditioner will not be able to remove the moisture from the air and maintain the proper temperature, resulting in the compressor running continuously in an attempt to cool the room. Check the condenser coils to determine if they are dirty. Refer to owner's manual for cleaning instructions.
Highly Likely
04 - Lennox Air Conditioner Temperature Control Thermostat
The temperature control thermostat is a sensor which monitors the temperature of the air and activates a switch to provide power to the fan and compressor when the air temperature drops below a set point. If the thermostat isn’t working properly, the air conditioner may not stay running long enough to remove the moisture in the air and cool properly. To determine if the temperature control thermostat is defective, use a multimeter to test it for continuity. If the thermostat does not have continuity, or is shutting off too soon, replace it. (Note: Some thermostats may also control a heater and, as a result, will have three...
Common
05 - Lennox Air Conditioner Thermistor
The thermistor is a sensor connected to the control board that detects the temperature of the air. The resistance value of the thermistor changes in conjunction with the air temperature. If the air temperature rises, the resistance value will decrease. To determine if the thermistor is at fault, use a multimeter to test it for continuity. If the thermistor does not have continuity, or if the resistance of the thermistor does not change with a change in temperature, replace the thermistor. (To find specific temperature and resistance values, try checking your user’s manual.)
Less Common
06 - Sealed System Problem
If the unit has good air flow, the evaporator and condensing unit coils are clean, the fans and compressor are running, but there is still not enough cooling, or moisture being removed from the air, it is likely there is a leak or restriction in the sealed system. Since diagnosing and repairing a sealed system takes specialized tools and knowledge, a qualified service technician should diagnosis and repair the unit.
Less Common
Frequently Asked Questions
Why is my Lennox air conditioner not removing humidity from the house?
Can a dirty air filter make my AC not dehumidify properly?
Why does my Lennox AC run continuously but the home humidity is still too high?
Could a Lennox air conditioner thermostat problem cause high humidity?
How do I find the right Lennox air filter, thermistor, or thermostat for my air conditioner?
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