When the “Cool On” light on your Honeywell thermostat keeps blinking, it might be confusing. Your thermostat may show this warning for several reasons, but it frequently denotes an AC issue. Follow along as we investigate the potential causes of why your Honeywell thermostat is showing a “Cool On” message and potential fixes.
In addition to their dependability and user-friendliness, Honeywell thermostats are among the best on the market. One of the best features of Honeywell thermostats is the user-friendly display since it provides simple access to essential information. So what does it signify when “Cool On” is glowing on your Honeywell thermostat?
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On a thermostat, what does cool mean?
A thermostat’s Cool feature allows you to regulate cool airflow throughout your home. When your Honeywell thermostat displays the phrase “cool on,” it’s ready to circulate cool air throughout your house.
You may need to troubleshoot Honeywell cool on if your thermostat is flashing cool on for an extended period, but you don’t feel cool air entering your home.
Honeywell Thermostat Flashing Cool On – What Does It Mean?
Here, the 5-minute standard is crucial because it acts as a safety net. After five minutes, the indicator should cease blinking “cool on,” indicating that cool air has been restored and that the HVAC system will resume regular operation. This occasionally could also happen if your air conditioner loses electricity.
Consequently, there are two possible reasons for your Honeywell thermostat to be blinking cool on:
Five-minute lag
It is causing the cooling process to begin. Before the cold air returns to your house, you can experience this delay and observe that your thermostat is blinking cool for up to five minutes.
This delay serves as a timeout mechanism in your device to safeguard your compressor from any potential harm caused by pressure variations.
Delay of more than five minutes
After five minutes, if the flashing continues, more serious issues should be investigated. Fortunately, a few troubleshooting techniques can quickly resolve the problem.
Why is the Honeywell thermostat flashing cool on?
As previously said, there won’t typically be a problem in this situation. Instead, that indicator will often be blinking due to your Honeywell Thermostat briefly losing electricity.
According to experts, one of the safety mechanisms in the device is functioning if the LED is flashing. During this process, your system’s compressor has enough time to cycle before being forced back into operation. Essentially, this prevents damage to the AC compressor, which can be expensive to replace.
If the light has been off for over five minutes and it is an isolated incident, everything is fine. Then, you need not be concerned. No issue has to be resolved. You will need to conduct some troubleshooting, though, if you see that the issue persists or if the light just never stops flashing.
Possible Reasons Why a Honeywell Thermostat Is Blinking Cool
In general, nothing to worry about if your thermostat flashes cool on. However, if the flashing continues for more than five minutes, your thermostat must be checked out.
Your Honeywell thermostat may flash “Cool On” as a result of the following circumstances:
Power outage
The thermostat compressor restarts whenever there is a power loss. This causes the thermostat to flash “cool on” for around five minutes before cool air circulates through the vents.
An immediate restart of the compressor
The compressor will have to restart if the temperature is manually adjusted soon after the HVAC system reaches the desired temperature.
Switching an air conditioner’s cooling or heating modes
The compressor will experience a lot of pressure, and your thermostat’s display will begin to flicker.
Changing the batteries
Your thermostat’s Cool On display can flicker after you recently changed the batteries.
Faulty wiring
A Honeywell thermostat might fail and display “Cool On” due to faulty wiring. Even after installation, electrical issues might arise if something is knocked loose. However, homeowners who connect their air conditioners and thermostats tend to have wiring issues more frequently.
Low battery
A thermostat may occasionally use the Cool On flash to tell you its batteries are running low. Unfortunately, older Honeywell thermostat models still communicate with flashing signals even though some feature a separate low battery indicator.
A Honeywell Thermostat That Is Flashing “Cool On”: How to Fix It
Here are several ways to fix a flashing “Cool On” Honeywell thermostat.
Restart the entire system
We advise you to switch off your entire system if the light is still flashing after five minutes.
After it has been turned off for a few minutes, turn it back on again. This occasionally results in a proper system reset and resolves the problem. However, most people find that the issue has now been adequately resolved.
Check the wiring
Has an HVAC expert rewired your Honeywell thermostat for the greatest results? But you can rewire it independently if that isn’t always possible. Your thermostat may be easily rewired by following a few easy procedures, which are as follows:
- Turn off the electricity
- Unplug the cables and identify them.
- Observe the wire color codes.
- Connect fresh wires to the AC unit from the control board.
The most crucial step is you must know the color codes for the wires that connect your control board to your air conditioner. The first error many do-it-yourselfers make while wiring their thermostat is to line the wires with the incorrect color. To avoid causing more harm, see a professional if reconnecting your thermostat to your air conditioner doesn’t work.
Examine the circuit breakers
As we previously stated, the Honeywell Thermostat will often flash if there is a power outage. As a result, we advise you to examine the HVAC system’s circuit breaker. Make certain that nothing has tripped.
If the circuit breaker has tripped and it keeps happening, you should probably go to an HVAC specialist because this might mean your system is broken. Although luckily, it is quite uncommon.
Lower the temperature to its lowest setting
Use this approach to determine whether or not your thermostat can control the temperature. The steps are as follows:
- By adjusting the controller settings, you may see if the cooling works.
- While the mode is on “Cool,” adjust the fan setting to “Auto.”
- Now lower the temperature to the absolute minimum.
- Leave it in the same setting for a few minutes and see if anything seems to have changed.
Check to see whether the thermostat is in setup mode or if the clock hasn’t been set after a blackout
This can be useful if there has been a power outage or blackout at your location. Most likely, the thermostat has been set to the setup mode.
Verify if the thermostat is turned off or not. The indicator would start to blink as a result. Configure and check the settings by the directions if any of these happen.
Examine the Batteries
In rare circumstances, the flashing light indicates that the thermostat cannot communicate a cooling signal to the air conditioner. It is likely that low batteries are to blame and that your thermostat’s batteries need to be changed. This is a quick task.
Take out your thermostat’s handbook if you are unsure how to change the battery. You will follow this along the way. The Honeywell Thermostats vary from one another.
Remember that certain Honeywell Thermostats only feature a battery as a backup power source. Your main supply will provide the majority of the electricity. You can skip this step if that applies to you.
Verify the Power of the HVAC System Components
- Humming or clicking sounds are indicators that a component of the system is malfunctioning.
- Verify whether or not the fans, furnace, air handler, or AC unit are powered.
- Verify that the connections are secure. Check that the supply and sockets are connected and turned on correctly.
- Check to see if any parts are loose and whether the doors are closed all the way.
- The device must be unobstructed and functioning correctly.
- To ensure there is no fault, you should flip the circuit breakers on and off. Now you can inspect the blown fuses using a voltmeter.
To check if the AC filter needs to be replaced
Overall cooling will still be compromised if the AC filter isn’t functioning correctly. To keep dirt and dust from blocking it, you must change it every three months.
The air conditioner has to work harder to chill the area if the filter becomes clogged. This causes the compressor and other equipment to pressurize. As a result, you could see a significant drop in temperature or experience issues with other HVAC parts.
Analyze the AC coils for dirt
The AC coils may become dusty, much like the AC filter. As a result, the outside coils need cleaning. Another possibility is that the HVAC system is blocked. Years of dust accumulation cause the coil to clog and stop allowing air to circulate. The coil’s inability to absorb heat has an impact on overall cooling.
Turn the appliance off, then clean the coils and the surrounding area. They won’t clog once more as a result. Ensure the unit is in a spacious, open area without obstructions like furniture or plants.
Reset the thermostat
This might be the last resort if everything else fails. The thermostat is back to its default settings. This eliminates all of the earlier data. Additionally, the gadget returns to its initial settings.
- Check the thermostat’s model first.
- Now, note the combinations as they stand.
- Remove any devices with a C-wire power source.
- To reset it, press and hold the “Menu” button for a brief period.
- Reset the device and then input the prior settings.
If nothing else works, consult the user manual or contact customer service for assistance.
Call a technical professional
Even after doing everything, a problem might occasionally remain a mystery. It will be necessary for this situation to contact a licensed engineer. It can be a simple fix for them to take care of for you.
Any malfunctioning capacitor, blown a fuse, blocked sensor, or damaged or defective wiring may all be fixed by a qualified expert. They can also determine whether the HVAC system’s compressor, condenser, or fan motor requires further maintenance.
Making sure the cables are all in the proper places might solve the problem for more recent installations. You may also get assistance from a qualified specialist in setting up the system correctly with your thermostat.
Review the instruction handbook
Checking the instructions for your specific thermostat is, of course, one of the most obvious answers. If you’re having trouble figuring out what went wrong, this information should be able to assist. There may even be unique advice for the Honeywell model you have.
No longer own your manual? You should be able to locate your thermostat on the Honeywell website or by contacting their customer service department as long as you know the model number.
Conclusion
Fortunately, this is the one light that does not always alert you to problems but usually offers you confidence that your HVAC system is still operational. And it’s often not a big deal to troubleshoot and fix the issue when the light is consistently flashing and signalling a system error.
We believe you have finally been able to resolve the mystery of why your Honeywell thermostat’s “cool on” indicator is flickering. Now that you are aware of precisely what this light represents, you should know how to fix it if it flashes continuously. Then, hopefully, you’ll save money and quickly have it functioning again.
