Honeywell Thermostat Won’t Turn on AC: Reasons and How to Fix

Last Updated on August 12, 2022 by Kimberly Crawford

Your Honeywell thermostat is one of the most important pieces of equipment in your home when it comes to your air conditioning. If it isn’t working properly, you could be in for a long, hot summer. In this blog post, we will discuss some common problems that can occur with your Honeywell thermostat and how to fix them.

Why Honeywell Thermostat Won’t Turn on AC?

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1. Batteries.

Check the batteries in your Honeywell thermostat. If the batteries are low, the screen will be blank. Replace the batteries with new ones and see if that fixes the problem.

If your Honeywell thermostat still won’t turn on the AC, there may be a problem with the power source. Check to make sure that the thermostat is plugged into an outlet and that the outlet is working. You may also want to try plugging the thermostat into a different outlet.

Why does it fail?

There are a few reasons your AC might not be working, but one of the most common is simply because the batteries in your Honeywell thermostat are dead.

This can easily be remedied by replacing the batteries with fresh ones – just make sure you use the right size and type of battery specified in your user manual. If that doesn’t solve the problem, then you may need to call a professional for help.

Another common reason why your AC might not be working is because the thermostat itself is set too low. Again, consult your user manual to make sure you’re using the thermostat correctly.

How to replace the batteries.

If your Honeywell thermostat won’t turn on the AC, it may be because the batteries are low. To replace the batteries:

-Remove the front cover of the thermostat.

-Locate the battery compartment and remove the old batteries.

-Install new batteries in the compartment and replace the cover.

2. Air filter.

The most common reason a Honeywell thermostat won’t turn on the AC is because the air filter is dirty. A clogged air filter restricts air flow and prevents the thermostat from reading the temperature correctly.

How do you fix it?

To fix this problem, simply replace the dirty air filter with a new one. Be sure to check the air filter monthly and replace it as needed.

3. Circuit breaker.

If your circuit breaker is flipped, your AC unit will not turn on. Check to see if the switch next to your furnace is in the “On” position.

If it is, then flip the breaker back to the “Off” position and wait a few minutes before flipping it back to the “On” position.

This should reset your AC unit and allow it to turn on. If your AC unit still does not turn on, then you may need to call a professional for assistance.

Why does it fail?

The answer is simple. The circuit breaker trips because the Honeywell thermostat is drawing too much power.

This usually happens because the AC unit is trying to turn on but there’s something wrong with it. Maybe the coils are frozen or the compressor isn’t working properly.

4. Wiring.

The next thing you should check is the wiring. If the wires are loose, it could be causing the problem. Check to see if the wires are connected properly and tightened. If they’re not, then tighten them and see if that fixes the problem.

5. Reset The Thermostat To Factory Settings.

If your Honeywell thermostat won’t turn on the AC, you may need to reset the thermostat to factory settings.

To do this, simply remove the batteries for 30 seconds and then replace them. This will clear any stored data in the thermostat and should fix the problem. If not, you may need to consult the Honeywell user manual for further troubleshooting steps.

Honeywell thermostat won’t turn on after replacing batteries

If your Honeywell thermostat won’t turn on after replacing batteries, it may be because the batteries are installed incorrectly. Try removing the batteries and reinstalling them. If that doesn’t work, you may need to replace the battery door.

Once you have replaced the batteries and/or battery door, try turning on the thermostat. If it still doesn’t work, there may be an issue with the thermostat itself and you will need to contact Honeywell customer service for assistance.

Honeywell thermostat won’t turn on after power outage

After a power outage, your Honeywell thermostat may not turn on. This can be frustrating, especially if the weather is cold and you’re trying to keep your home warm. There are a few reasons why this may happen, and fortunately, there are also a few things you can do to fix it.

One reason why your Honeywell thermostat may not turn on after a power outage is because the batteries are dead. If this is the case, simply replace the batteries and see if that does the trick.

Another reason why your Honeywell thermostat may not turn on after a power outage is because it was not properly reconnected to the power supply. If this is the case, you’ll need to find the right power supply and reconnect it.

How do I reset my Honeywell thermostat after a power outage?

First, check to see if your thermostat is still on the correct time and day. If it is not, simply change it. If your Honeywell thermostat was displaying a low battery message before the power went out, you will need to replace the batteries.

To do this, remove the front cover of the thermostat and locate the batteries. Once you have replaced the batteries, reattach the front cover. Finally, check to make sure that all of your thermostat’s settings are correct. If they are not, you can adjust them as needed.

Can a power surge damage a thermostat?

Yes, a power surge can damage a thermostat. A power surge is an sudden increase in voltage that can damage electronic equipment. Thermostats are electronic devices and can be damaged by power surges. If you have a power surge, you should unplug your thermostat to prevent it from being damaged.

What happens when Honeywell thermostat goes blank?

If your Honeywell thermostat screen goes blank, there are a few possible reasons why. The most common reason is that the batteries need to be replaced.

If the batteries are not the issue, it could be due to a power outage or a problem with the wiring. If you’re not sure what the problem is, you can try resetting the thermostat. If that doesn’t work, you may need to contact a professional for assistance.

Why is my thermostat not turning on the AC?

There are a few reasons this could be happening. First, check to make sure that the thermostat is set to “cool” mode and that the temperature is set lower than the current room temperature. Also, ensure that the fan switch is in the “on” position.

If these things are all set correctly and the AC still isn’t turning on, there may be an issue with the power supply or with the AC unit itself.

If you suspect there may be a problem with the AC unit, it’s best to call a professional for assistance. Trying to fix the issue yourself could result in further damage.

How to turn on AC with old Honeywell thermostat.

If your old Honeywell thermostat has a knob instead of buttons, you may need to hold down the “Mode” button for about three seconds before rotating the knob to the “Cool” position.

Some models also have a switch that must be in the “On” position for the AC to work. Again, consult your thermostat’s manual if you’re unsure. Finally, set the temperature to your desired level and voila! You should now have cool, refreshing air flowing through your home.

Conclusion

If your Honeywell thermostat won’t turn on your AC, there are a few potential causes. First, check to see if the batteries are low. If they are, replace them and try again. If that doesn’t work, you may need to reset the thermostat. To do this, simply turn it off and then back on again. If that doesn’t work, you may need to call a professional for help.

We hope this article has helped you troubleshoot your Honeywell thermostat issue. If you have any other questions or concerns, please feel free to reach out to us. We’re always happy to help! Thanks for reading!