Why is My Mini Split Blinking? A Comprehensive Troubleshooting Guide

A blinking light on a mini split air conditioner can indicate various issues, depending on the brand and the blinking pattern. The problem could be related to a time delay, low refrigerant level, fan motor issues, or more complex internal faults. Identifying the blink pattern and following a systematic troubleshooting process is crucial to resolving the problem effectively.

Identifying the Blink Pattern

The first step in troubleshooting a blinking mini split is to identify the specific blink pattern. This information can provide valuable clues about the underlying issue. Different brands and models may have unique blink patterns that correspond to different problems. For example:

  • CONFORTotal wall units may flash a temperature light when the unit is stuck in a time delay, particularly when switching from cooling to heating mode.
  • Mitsubishi mini splits often blink a green light when there’s a low refrigerant level, a problem with the indoor unit’s fan motor, or an electrical issue.
  • Fujitsu halcyon mini splits might blink in a specific pattern when there’s a refrigerant issue, a motor problem, or a more intricate internal fault.

By carefully observing the blink pattern, you can narrow down the potential causes and tailor your troubleshooting efforts accordingly.

Performing a Power Reset

why is my mini split blinkingImage source: Flickr

One of the first steps in troubleshooting a blinking mini split is to perform a power reset. This simple procedure can often resolve various issues, including those that may be causing the blinking light. Here’s how to do it:

  1. Turn off the air conditioner using the remote control.
  2. Disconnect the unit from its power source, either by unplugging it or turning off the circuit breaker.
  3. Wait for approximately 30 seconds to 1 minute.
  4. Reconnect the power and turn the air conditioner back on.

This power reset can help clear any temporary glitches or reset the system, potentially resolving the blinking light issue.

Checking Filters and Vents

Dirty air filters or blocked air vents can also trigger a blinking light on a mini split. Ensure that the filters are clean and replace them if necessary. Additionally, check all air vents and pathways to ensure they are clear and unobstructed. Restricted airflow can cause the system to malfunction, leading to the blinking light.

To clean the filters:

  1. Locate the indoor unit and remove the front panel or access cover.
  2. Carefully remove the air filters, following the manufacturer’s instructions.
  3. Use a vacuum cleaner or soft brush to remove any accumulated dust and debris.
  4. Rinse the filters with clean water, if recommended by the manufacturer.
  5. Allow the filters to dry completely before reinstalling them.

Examining External Factors

Environmental factors, such as temperature fluctuations or changes in humidity, can also affect the performance of a mini split and trigger a blinking light. Consider the following external factors:

  • Ambient temperature: Extreme temperatures, either hot or cold, can put additional strain on the system and cause it to malfunction.
  • Humidity levels: Sudden changes in humidity can affect the system’s ability to maintain the desired temperature and humidity levels, leading to issues.
  • Direct sunlight: Exposure to direct sunlight can cause the system to work harder, potentially leading to problems.

If you suspect that external factors are contributing to the blinking light issue, try adjusting the thermostat settings or relocating the indoor unit to a more suitable location.

Troubleshooting Mitsubishi Mini Splits

For Mitsubishi mini splits, the blinking light may indicate specific issues related to the fan motor or electrical components. Here’s how to troubleshoot these problems:

Fan Motor Issues

  1. Turn off the power to the unit and remove the cover of the indoor unit.
  2. Inspect the fan to ensure it is spinning freely without any obstructions.
  3. If the fan is not spinning freely, try oiling the motor to see if that resolves the issue.
  4. If the fan is spinning freely but the blinking light persists, the motor may be burned out and need to be replaced.

Electrical Issues

  1. Check the circuit breaker to ensure that it has not tripped.
  2. If the breaker is not tripped, inspect the wiring connections within the unit to ensure they are secure and free of any damage.
  3. If the wiring appears to be in good condition, the issue may be more complex, and you may need to contact a professional HVAC technician for further assistance.

Seeking Professional Assistance

If you have followed the troubleshooting steps and are still unable to resolve the blinking light issue on your mini split, it is recommended to contact a professional HVAC technician. They have the expertise and specialized tools to diagnose and repair more complex problems that may be beyond the scope of a DIY approach.

Remember, attempting to repair a mini split without the proper knowledge and equipment can be dangerous and may even void the manufacturer’s warranty. It’s always better to err on the side of caution and seek professional help when necessary.


A blinking light on a mini split air conditioner can be a frustrating issue, but with the right troubleshooting approach, you can often identify and resolve the problem. By following the steps outlined in this comprehensive guide, you can systematically diagnose the issue, from identifying the blink pattern to examining external factors and addressing specific problems like fan motor or electrical issues.

If you are unable to resolve the problem on your own, don’t hesitate to contact a professional HVAC technician. They have the expertise and tools to diagnose and repair even the most complex mini split issues, ensuring your system is back in working order and providing you with the comfort you expect.

– https://www.reddit.com/r/hvacadvice/comments/yx2doj/confortotal_wall_units_started_flashing_the_temp/
– https://www.youtube.com/watch?v=9ZAnQj2oQmg
– https://hvac-talk.com/vbb/threads/2230261-Fujitsu-halcyon-mini-split-blinking-not-working