Honeywell Thermostat is Blinking Cool On: Fixing Guide!

If your Honeywell thermostat is blinking cool, it may indicate a problem with the cooling system. This issue could be due to a malfunctioning sensor or a lack of power to the cooling system.

It’s important to troubleshoot the thermostat and the cooling system to identify and resolve the issue. A blinking cool indicator on your Honeywell thermostat can be a cause for concern, as it may indicate that your cooling system is not functioning properly.

This could lead to discomfort in your home and potentially higher energy bills. In this blog post, we will explore the possible reasons why your thermostat is blinking cool and provide troubleshooting tips to help you resolve the issue. By following these steps, you can ensure that your home remains comfortable and your cooling system operates efficiently.

Identifying The Blinking ‘Cool On’ Signal

If your Honeywell thermostat is blinking “Cool On,” it means the cooling system is activated. Check the settings to ensure it’s set to your desired temperature. If the issue persists, consult the thermostat manual for troubleshooting steps.

If your Honeywell thermostat is blinking ‘Cool On’, it means that your cooling system is not functioning correctly. You must identify the root cause of the issue to get it fixed as soon as possible. In this post, we will discuss the common causes of blinking, how to decipher the blink pattern, and what actions you can take to resolve the issue.

Common Causes Of Blinking

The blinking ‘Cool On’ signal on your Honeywell thermostat can indicate various issues, including:

  • Dirty air filters
  • Low refrigerant levels
  • Malfunctioning compressor
  • Issues with the thermostat
  • Dirty condenser coils

If the issue is related to dirty air filters, then simply replacing them could resolve the problem. However, if the issue is more severe, such as low refrigerant levels or a malfunctioning compressor, then you will need to call a professional HVAC technician to take a closer look.

Deciphering The Blink Pattern

If your Honeywell thermostat is blinking ‘Cool On’, it is essential to decipher the blink pattern. Typically, the blink pattern can help you identify the specific issue with your cooling system. Here are some common blink patterns and their meanings:

Blink Pattern Meaning
1 blink every 5 seconds Low battery signal
2 consecutive blinks System wait (time delay)
3 blinks Pressure switch fault
4 blinks Open limit device
5 blinks Flame sensing abnormality

Identifying the root cause of the ‘Cool On’ blinking signal on your Honeywell thermostat is crucial to maintaining a comfortable home environment. By understanding the common causes of blinking, deciphering the blink pattern, and taking necessary actions, you can resolve the issue and ensure that your cooling system is functioning correctly.

Initial Troubleshooting Steps

When your Honeywell thermostat is blinking cool, there are initial troubleshooting steps you can take to resolve the issue.

Checking The Power Supply

1. Ensure the thermostat is properly connected to a power source.

2. Check for any tripped circuit breakers or blown fuses.

Inspecting The Thermostat Screen

1. Look for any error messages or alerts on the display.

2. Make sure the thermostat is set to the correct mode and temperature.

Thermostat Settings And Configuration

When it comes to maintaining a comfortable indoor environment, understanding your Honeywell thermostat’s settings and configuration is essential. By reviewing the schedule program, adjusting temperature settings, and addressing any warning signals, you can ensure that your thermostat is operating efficiently and effectively.

Reviewing The Schedule Program

To optimize the functionality of your Honeywell thermostat, it’s crucial to review and adjust the schedule program. This allows you to customize the temperature settings based on your daily routine, ensuring energy efficiency and comfort. By accessing the scheduled program, you can create a personalized heating and cooling plan that aligns with your lifestyle.

Adjusting Temperature Settings

Adjusting the temperature settings on your Honeywell thermostat is straightforward and can have a significant impact on energy consumption and indoor comfort. By fine-tuning the temperature levels for different times of the day, you can maximize efficiency without sacrificing comfort. Whether you prefer a cooler environment during the night or a warmer setting in the morning, the thermostat’s temperature settings can be customized to suit your preferences.

Filter Check And Replacement

Locating The Air Filter

Locating the air filter in your Honeywell thermostat is essential for ensuring your HVAC system operates efficiently. In most models, the air filter is typically located behind the front cover, within the return air duct or air handler. Refer to your thermostat’s user manual for specific instructions on locating the air filter.

When To Replace Your Filter

Regularly replacing your air filter is crucial for maintaining indoor air quality and maximizing the performance of your HVAC system. It is recommended to replace the filter every 60-90 days, or sooner if you have pets or suffer from allergies. A clogged filter can lead to reduced airflow, causing your HVAC system to work harder and consume more energy.

Circuit Breaker And Power Issues

When dealing with your Honeywell thermostat blinking cool, it’s important to consider circuit breaker and power issues that may be causing the problem. Resetting the circuit breaker and dealing with frequent power surges can help resolve the blinking cool issue.

Resetting The Circuit Breaker

If your Honeywell thermostat is blinking cool, check the circuit breaker for any tripped switches. Locate the circuit breaker panel and identify the breaker corresponding to your HVAC system. Flip the breaker switch off and on to reset it. This may resolve the issue causing the blinking cool on your thermostat.

Dealing With Frequent Power Surges

Frequent power surges can cause your Honeywell thermostat to blink cool. Consider installing a surge protector to safeguard your HVAC system from power fluctuations. It is essential to address any underlying electrical issues to prevent frequent power surges that affect your thermostat’s performance.

HVAC System Checks

When your Honeywell thermostat is blinking “Cool On,” it’s important to perform HVAC system checks to ensure that everything is functioning properly. Understanding system delays and implementing preventive maintenance tips are crucial for keeping your HVAC system in top condition.

Understanding System Delays

System delays can occur due to various factors, such as temperature differentials, compressor protection, or system recovery. It’s essential to understand these delays to prevent unnecessary troubleshooting or potential damage to your HVAC system.

Preventive Maintenance Tips

Implementing regular preventive maintenance measures can help prolong the life of your HVAC system and prevent issues such as the “Cool On” blinking on your Honeywell thermostat. Here are some tips to keep your system running smoothly:

  • Change air filters regularly to ensure proper airflow and system efficiency.
  • Inspect and clean the outdoor unit to remove any debris or obstructions that could hinder performance.
  • Check and clean the evaporator and condenser coils to maintain optimal heat transfer.
  • Ensure proper sealing and insulation of ductwork to prevent air leaks and energy waste.

Professional Assistance Vs. Diy Repair

Experience the difference: Opt for professional assistance for a blinking cool Honeywell thermostat. DIY repair may lead to further complications. Trust experts for reliable solutions.

When To Call An HVAC Technician

When you notice the Honeywell Thermostat blinking cool, it may be time to seek professional assistance.

Simple Fixes You Can Do Yourself

If the issue seems minor, try these DIY steps before calling a technician:

  • Check thermostat settings and batteries.
  • Ensure the thermostat is set to cool mode.
  • Inspect for loose or damaged wiring.

Deciding between calling an HVAC technician or attempting a DIY repair can be challenging.

Considering the complexity of the issue and your comfort level with troubleshooting can help you make the right choice.

While simple fixes like checking settings and wiring can be done independently, more intricate problems may require professional expertise.

Preventing Future Blinking Issues

To prevent future blinking issues with your Honeywell Thermostat flashing “Cool on,” start by checking the thermostat’s display for error codes. Ensure that the thermostat is properly connected and that the settings are correct. If the issue persists, consider resetting the thermostat or contacting a professional for assistance.

Regular Thermostat Maintenance

Regular maintenance of your Honeywell thermostat is essential to prevent future blinking issues. Cleaning the thermostat regularly is one of the most straightforward maintenance practices that can be done. Dust and debris accumulation on the thermostat can cause it to malfunction and lead to blinking issues.

Use a soft cloth to wipe the thermostat to keep it clean and dust-free. Another regular maintenance practice is to check the thermostat wiring for any loose connections. Loose connections can cause a disruption in the thermostat’s functioning, which can lead to blinking issues. Make sure all the wires are connected correctly and securely.

Upgrading Your Honeywell Thermostat

If your Honeywell thermostat is outdated, upgrading to a new one can help prevent future blinking issues. Newer thermostats come with advanced features that enable them to operate more efficiently. They are also more accurate and reliable, which reduces the likelihood of blinking issues.

When upgrading, consider buying a programmable thermostat. These thermostats allow you to set different temperature schedules for different times of the day. With a programmable thermostat, you can set the temperature to increase or decrease automatically, which saves energy and reduces your energy bills.

Preventing future blinking issues with your Honeywell thermostat is crucial. Regular maintenance practices such as cleaning the thermostat and checking the wiring for loose connections can help keep your thermostat functioning correctly.

Upgrading to a new thermostat with advanced features such as programmable thermostats can also help prevent future blinking issues. Taking these steps ensures that your Honeywell thermostat operates smoothly and efficiently.

Frequently Asked Questions

Why Is The Honeywell Thermostat Flashing Cool On?

The Honeywell thermostat is flashing “cool on” to indicate that the cooling system is activated. It’s a normal display when the thermostat is set to cool mode. This flashing message means the cooling function is active and the system is operating to lower the temperature.

How Do I Reset My Honeywell Thermostat Cool On?

To reset your Honeywell thermostat to cool mode, locate the mode button and select “Cool. ” Adjust the temperature setting as needed.

Why Is My Thermostat In Delay Mode?

Your thermostat may be in delayed mode due to system protection or a temporary malfunction. Check for any error codes displayed for troubleshooting.

Why Is My Thermostat Blinking Wait Cool?

A blinking “Wait Cool” message on a thermostat is an indication that the cooling system is in a temporary delay mode. This delay happens to protect the compressor of the AC unit from damage due to frequent on/off cycles. The delay may last for several minutes, after which the AC unit will start cooling again.


Ensure your Honeywell thermostat is functioning optimally by addressing the blinking cool notification promptly. Understanding the causes and solutions can help maintain a comfortable indoor environment. Regular maintenance and professional assistance can prevent further issues. Stay proactive to enjoy consistent temperature regulation in your home.

Scott Maupin