in , , ,

How To Troubleshoot A Lennox Air Conditioner

How To Troubleshoot A Lennox Air Conditioner

When your Lennox air conditioner is not functioning properly, there’s no need to immediately call an HVAC professional. Troubleshooting your Lennox AC can be done easily, and we’ve compiled a detailed guide to help you diagnose and resolve common issues without professional assistance.

Troubleshooting A Lennox Air Conditioner

To effectively troubleshoot your Lennox air conditioner, follow these steps:

  1. Inspect the remote control: Start by checking the batteries in your air conditioner’s remote control. Low battery levels can prevent proper command of the AC unit.
  2. Check the fuse, circuit breakers, or switches: If the remote control inspection doesn’t resolve the issue, examine the circuit breaker to ensure it hasn’t tripped. Additionally, check for blown fuses and inspect any open isolating switches.
  3. Check the air filters: Dirty air filters are a common cause of reduced efficiency and performance in air conditioners. Remove the filters and clean them using water, dish soap or vinegar, and dry them thoroughly before reinstalling.
  4. Inspect the inlets and outlets: Blockages or interference in the inlets and outlets can disrupt airflow and hinder the AC unit’s performance. Keep these areas clear of any obstructions.
  5. Reset the air conditioner: If the previous steps haven’t resolved the issue, try resetting your Lennox air conditioner. However, it’s important to note that you should only reset the unit once. If the problem persists, it’s advisable to seek professional help.

Resetting A Lennox Air Conditioner

How To Troubleshoot A Lennox Air Conditioner
  1. Switch off the air conditioner.
  2. Locate the circuit breaker box and find the breaker assigned to your AC unit.
  3. Reset the air conditioner by toggling the circuit breaker.
  4. Wait for a minute before switching the thermostat on again.

Troubleshooting The Thermostat

How To Troubleshoot A Lennox Air Conditioner

In addition to troubleshooting the air conditioner itself, it’s important to check the thermostat as well, as it can sometimes be the source of the problem.

  1. Check the batteries and replace them if necessary.
  2. Inspect the circuit panel for any tripped breakers.
  3. Ensure all electrical connections are secure by removing the thermostat from its mounting and checking the wire contacts. Refer to the owner’s manual for further instructions.

Lennox Air Conditioner Common Issues

  1. The unit is operating too loudly: Noisy air conditioners can be caused by various factors, such as worn-out fan motor bearings, a deteriorating compressor, or loose fan blades. In such cases, it is recommended to replace the faulty components rather than the entire unit.
  2. The unit won’t blow cold air: If your Lennox air conditioner fails to produce cool air, inspect the compressor for any issues. Additionally, check the disconnect box, fuse, and breakers between the condensing unit and circuit breakers. Faulty thermostats can also cause inadequate cooling.

Lennox Air Conditioners Frequently Asked Questions (FAQs)

How To Troubleshoot A Lennox Air Conditioner
  1. Is Lennox Air Conditioning a reputable company?
    Lennox is a reputable brand with a reputation for offering hygienic, chilly, and silent functioning. Their models frequently have high SEER ratings, which, when kept in good condition, indicate efficiency and dependability.
  2. How long is the lifespan of a Lennox air conditioner?
    With the right maintenance, Lennox air conditioners can last up to 15 years or even longer.
  3. Can I easily swap out the outdoor air conditioner?
    Even though replacing just the exterior unit is an option, it may not be as efficient as replacing the full system.
  4. Can I change a Lennox AC unit on my own?
    A skilled HVAC contractor should replace an air conditioner unit to ensure correct installation and avoid operating problems.
  5. Can I just swap out the AC coils?
    An air conditioner’s coils can be replaced alone, but it is advised to perform a diagnostic test to evaluate the system as a whole to see if a total replacement is required.
  6. How frequently should evaporator coils be cleaned?
    For optimum efficiency, evaporator coils should be cleaned at least once a year. Coils that are dirty might use more energy and strain the system.
  7. How can I tell if the coils in the air conditioner are damaged?
    Warm air entering from the vents, the unit cycling on and off without providing enough cooling, strange noises (such as banging or hissing), indoor unit leaking, and failure to turn on even after several tries are all indications that the coils need to be replaced.
  8. Why is my house not being cooled by my Lennox air conditioner? Check the condenser for debris or obstructions if the air conditioner is on but not cooling the space. Clean the outdoor unit and trim back any bushes or weeds that could be in the way.
  9. Why is my Lennox Air Conditioner not turning on?
    A common reason for an AC unit not turning on is a tripped circuit breaker. Check the circuit breaker first, and if that’s not the issue, inspect the thermostat. A faulty thermostat may not properly communicate with the air conditioner.
  10. What is the difference between single-stage and two-stage air conditioners?
    Single-stage air conditioners operate at a fixed capacity, cooling the home at maximum output. In contrast, two-stage air conditioners have two levels of operation: high for hot days and moderate to low for milder weather.


This thorough manual offers detailed directions for troubleshooting Lennox air conditioners. Without the assistance of a professional, you can find and fix common problems by using the indicated troubleshooting techniques. To ensure appropriate repair and upkeep of your Lennox air conditioner, it is advised to get assistance from an HVAC specialist for more complicated issues or if the troubleshooting methods do not cure the problem.

How To Troubleshoot A Lennox Air Conditioner

What do you think?

Written by HVAC Contributor

Leave a Reply

Your email address will not be published. Required fields are marked *

GIPHY App Key not set. Please check settings

The Best Way To Clean A Sharp Air Conditioner

The Best Way To Clean A Sharp Air Conditioner

GE Air Conditioner Beeps But Won't Turn On: Why And How To Fix It?

GE Air Conditioner Beeps But Won’t Turn On: Why And How To Fix It?