Honeywell Thermostat Not Cooling – 7 Easy Fixes

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Thermostats have got to be one of the best human inventions. Imagine the discomfort we would have to endure in the summer without thermostats. There are many thermostat types, but Honeywell thermostats are some of the most famous.

They typically tell you when the cooling is on with a blinking light on the display with the message “cool on.” That means the thermostat is now cooling your home. But then sometimes you see the Honeywell thermostat not cooling even with the ‘cool on’ indicator showing it’s working.

How do you fix that? Here’s how.

Honeywell Thermostat Not Cooling? Follow these checklists

Wait Five Minutes

You should wait five minutes because the thermostat might only be in delay mode. In delay mode, you will see the thermostat show it’s cooling your home, but you won’t see any change in the room temperature.

So, waiting five minutes will tell you if the thermostat is in delay mode are there is a deep-lying issue. Delay mode typically lasts five minutes, although this could vary with the thermostat model.

Try the next step if it doesn’t exit delay mode after waiting for some time.

Change the BatteriesReplace Home Thermostat Battery-Honeywell

Sometimes a low battery could be why the thermostat is not cooling even after you instruct it. The low battery usually has enough power to power on the thermostat but does not ensure cooling.

That’s why checking the batteries and changing them might help. To change the batteries, you only need to press the side of the thermostat to remove the battery compartment.

After removing the battery compartment, replace the batteries with new ones and replace the battery compartment in the thermostat. The thermostat should start coiling soon afterward if the batteries were the problem.

Remember to use the same brand of batteries you bought the thermostat with.

Check for issues with the Indoor AC FilterWhat to Know About Replacing Your Air Conditioner Filter

Sometimes what you think is an issue with your thermostat might be because of the AC filter. The Ac filter will naturally accumulate much debris, thanks mainly to its work.

Once the debris clogs the filter, the AC and its components won’t work as efficiently as before. This will lead to the thermostat not cooling when you turn it on.

Fortunately, there is a solution for all of this: cleaning the filter. A better way to prevent that is to change the filter every three months, depending on how much you use your AC.

Remember that an inefficient AC filter will lead to higher power bills besides the occasional malfunctioning of the AC.

Check the Furnace Door and Its Power Switch

Sometimes the thermostat will not cool your home if you leave the furnace door open. This is a protective measure for the operation of the thermostat. It would be best to close the door for the thermostat to work.

If you’ve closed the door but haven’t turned on the power switch, there will still be no cooling. So, check the power switch and confirm if it is on. That should help set the ball rolling in the thermostat cooling your home.

Inspect the AC Coils for Dirt and DebrisDirty Evaporator Coils Are Killing Your AC

It isn’t only the filter that attracts dirt. The AC coils also attract dirt. When the dirt accumulates on the coils, it gets in the way of the airflow, causing problems for your AC.

The AC won’t cool or warm the incoming air as efficiently as it should. You thus find that although your thermostat is in cool mode, there isn’t any cooling happening.

The best way to prevent that is to clean the external coils regularly. Before cleaning, ensure the central unit is off before starting. An interval of two to three months should be good enough to keep the coils clean and your Ac functioning optimally.

Reset the ThermostatHow To Reset A Honeywell Thermostat

Sometimes it isn’t because of dirty coils or an open furnace door that the thermostat won’t cool. It might be down to software issues that will require you to reset the thermostat. Now, remember that resetting your thermostat will be like starting afresh.

Everything you had saved on it, including the maximum and minimum temperature values, will need you to enter them again.

Here is how to reset your Honeywell thermostat:

  • Locate the menu button on the thermostat
  • Long press the button to get several options
  • On the many options, select the reset
  • Say yes to the prompt, then reset.

Read Also: How To Remove Old Honeywell Thermostat from Wall – 6 Easy Steps

Seek Help From an HVAC Specialist

If all the other fixes fail, that is enough for you to call an HVAC professional. HVAC professionals know all there is to know about thermostats. A certified professional will therefore help diagnose the issue and help resolve it.

Contact Honeywell Support

If all the fixes fail, then the last resort measure is to call Honeywell customer support for their input. If the thermostat has a warranty, it will help you solve the issue for free or get a replacement.

What To Do When Honeywell Thermostat Set to Cool but Heating

Sometimes, the thermostat ups the heat instead of cooling your house with the cool function on. That can be frustrating, especially if you can’t solve it.

The below troubleshooting tips should help in that regard.

Confirm that the Thermostat Setup Mode

In setup mode, the thermostat will display the settings icon. That means the cool function could be on, but there isn’t any cool air. You will only have to complete the thermostats set up to solve this, and everything goes back to normal.

Besides the settings icon, also check for the clock. That will mean you have to set the correct time and ensure the clock is on.

Set the Lowest TemperatureWhat's the Recommended Temperature for Vacant Home in Winter?

Put the thermostat in cool mode, then set it to the lowest temperature for some time. Check to see if it stops heating instead of cooling the air. Setting different temperatures will also help solve the heating instead of cooling issues.

A specialist could also help you solve the problem if all the fixes you attempt to don’t work.

At The End

We hope you now know the fixes to try when you see your Honeywell thermostat not cooling. You can mealy fix the issues yourself if you follow the tips provided here.

If they don’t work, calling a specialist will help solve it. All the best.

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