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Honeywell Thermostat Blinking “Cool On”? (With Solutions)

Honeywell Thermostat is a device that is used in the home to maintain the temperature by increasing or decreasing the heat. In today’s article, we will discuss the thermostat blinking and provide you with solutions to it. 

Why is the word “cool on” flashing on my Honeywell thermostat? 

A Honeywell thermostat is a box that is installed inside the walls of your home and shows the current temperature. The thermostat display showing cool on is an operation that’s controlled by the thermostat itself. It means the AC is pumping cool air into your home.  

A Honeywell thermostat is a device that maintains the temperature in your home. If you have a Honeywell thermostat in your home and it shows cool on indicator flashing, it may mean one of a few things. 

The first thing it may mean is that the AC system is starting, which will take some time to become fully functional and it’s normal for the thermostat. The cool indicator is a feature that is regulated by the Honeywell thermostat. 

If the indicators start to flash it means the thermostat informs you that it has started to work. As a result, your AC will be turned on. Below is a brief discussion on the reasons why the word cools on flashing on your Honeywell thermostat:  

The AC is turning on: 

The first reason why the cool indicator is flashing in your Honeywell thermostat is that the AC is turning on. It is supposed to flash the light on the Honeywell thermostat which is very common for the device. 

This could lead to serious issues with your AC and cause you an expensive repair. But there may be other malfunctions that may be causing the device to flash the indicator. 

Battery malfunction on the thermostat: 

If the indicator light starts to flash, you need to check the battery of your thermostat. If they do not have enough power to control the AC in your home, it will start to flash the indicators due to lack of power. 

This may also cause disturbance to the operation of your AC. So, you need to check your AC units’ coil and make sure to turn off the unit before cleaning the coil.

In addition to that, to avoid further AC malfunction, you can simply clean the entire AC.

Dirty AC coils and filters: 

You need to check your AC unit if it has power and also checks the filters and the coils. Sometimes blocked external AC coils may cause the AC to operate for a long-time since it cannot cool the temperature in your room properly. 

So, this may be the main reason why the cool-on indicator is flashing on the Honeywell thermostat.

What does it mean when cool on is flashing on the thermostat?  

The main reason why “cool on” flashes on the Honeywell thermostat is because it is turning on the AC. This happens when the AC needs to be functional repeatedly.

Apart from that, there are some other reasons such as the battery malfunction or circuit breaker tripping. If it shows cool on flashing in the thermostat, it will surely mean something is wrong or not functioning properly in the thermostat. 

When fixing the Honeywell thermostat “cool on” issue, it will be a great idea to check the air conditioner if it has any type of issue that is connected to the thermostat device. 

Because an AC with dirty and clogged components can cause a serious system error. So, you need to be careful when observing the issue on the thermostat. Below is a brief discussion on what does it mean when cool on mode is flashing on the thermostat:

The thermostat is in delay mode: 

Sometimes if the temperature you have set in your thermostat does not match with your AC. It means the AC may want to pump cool air in the room but the thermostat has already reached the required temperature, as a result, it goes to delay mode. 

The thermostat has a lower battery: 

If the thermostat is having a lower battery, it will not be able to provide the right reading for the device, as a result, it will start to flash cool on repeatedly. So, there’s a possibility of having a low battery in your thermostat

An expected power surge: 

If your thermostat has faced an unexpected power surge, it may have started to behave abnormally. Also, it may put pressure on the compressor and may cause the AC to be functional for long. 

Honeywell thermostat cool on but not working:

If the Honeywell thermostat has, it’s cool on but not working you do not need to worry about that. The thermostat may be in delay mode and will take up to five minutes to become fully functional

There are some reasons why the thermostat goes into delay mode. The first reason is it helps to perfect the equipment such as an air conditioner from short cycling. On the other hand, you may need to check some other components. 

For example, you may need to check if the thermostat has been correctly configured with your system. If not, the thermostat will be on but won’t work with the AC. 

Generally, the thermostat display has an option to call for cooling, which is usually indicated by the words cool on or a snowflake icon. 

If the thermostat cooling indicator starts to flash but does not work, you need to wait for a couple of minutes for it to become fully functional.

Honeywell thermostat flashing cool on – How to fix it?  

In case you’re simultaneously facing the Honeywell thermostat, flashing cool on but not working, you may need to troubleshoot the device and fix the issue. 

Firstly, when the thermostat displays cool on, it generally means an operation mode that’s controlled by the thermostat connected to the AC. It indicates that the AC is working to pump cool air inside the house. 

But if you notice that the Honeywell thermostat is flashing for a long time but there’s any cool air flowing inside your home, there could be an issue. 

You should not neglect the malfunction of the thermostat because it may affect the device or the AC connected to the thermostat and cause you with an expensive repair if it gets damaged. 

So, you need to follow some troubleshooting steps to fix the issue. Below is a brief discussion on how to fix a Honeywell thermostat flashing cool on the issue: 

Change the batteries:

Honeywell thermostat requires the battery to operate effectively. The batteries need to be changed or replaced after a certain period to maintain the functionality of the Honeywell thermostat. 

You need to take a look at the battery indicator to make sure the batteries are low. Once you see the message, you have to change the batteries. This will help to work the thermostat effectively with the AC. 

Examine the AC:

Once you have fixed the issues in the thermostat now you should look forward to fixing the issues in your AC. There can be multiple issues such as the dirty or clogged air filter which may affect the system of the air conditioner. 

Sometimes the AC may require higher electricity consumption and cause you expensive electricity bills. Apart from that, you also may need to check the AC coils. Dirty AC coils can also lead to the thermostat blinking cool on. 

Reset the thermostat:

Like every other electronics, you can simply reset the thermostat to bring it to the default settings. 

As a result, the blinking issue of the Honeywell thermostat “cool on” will hopefully be gone. Resetting the thermostat will also help you to create a connection between the AC and the thermostat seamlessly.

How to reset Honeywell thermostat?  

Reseating the Honeywell thermostat is not a complicated job. It is a battery-operated device that is used to maintain the temperatures inside your house. 

Due to some technical issues, your Honeywell thermostat may behave abnormally. You can simply reset the Honeywell thermostat to prevent this type of issue from causing damage to your thermostat.

Firstly, you need to power off the thermostat and remove the batteries if it has. Check if the batteries are placed correctly. Wait at least 10 seconds and put the batteries inside the thermostat device in correct order. 

No need to push any button or do anything to reset the device. Turning it on after changing the batteries will bring it to the default setting. 

Once you reset the device, it will fix the “cool on” issue as well. This is how you can fix the thermostat blinking cool on the issue.

Final Thoughts 

The reason why Honeywell thermostat blinking cool on is maybe the thermostat devices taking delay time to prevent the AC from short cycling. However, the cool on flashing may indicate that the AC is pumping cool air into your home. The blinking is supposed to go away within 5 minutes.