Honeywell Thermostat Not Working: Guide To Troubleshoot

The article describes how to identify the type of thermostat you have and which troubleshooting method will be most effective if Honeywell Thermostat Not Working and HVAC system is not working

Turns out, Honeywell Thermostat Not Working issues are rather frequent, and there are various troubleshooting ways you may try to get the system back up and running.

The internet contains a wealth of information, but the majority of it is dispersed. As a result, I’ve compiled this article to guide you through the process of troubleshooting your Honeywell thermostat system.

If your Honeywell Thermostat isn’t working properly, try replacing the batteries or performing a hard reset.

How can I repair a not working Honeywell thermostat?

Do these to Repair a Broken Honeywell Thermostat

All of the thermostat’s cords must be unplugged.
Remove the device from the wall plate.
After the batteries are removed, five minutes should elapse.
Batteries and cables should both be replaced.
After turning on the system, wait five minutes.

Is there a reset button on a Honeywell thermostat?

Restore factory defaults: The Honeywell T5+ / T5 / T6 Pro Series Thermostats should be reset according to the instructions below: Check that the device is turned on (it should be on). Hold down the menu button for five seconds. Go to the left until you reach “Reset.”

Know the type of your thermostat

Honeywell manufactures three different types of thermostats. If you are unsure, small indicators can be utilized to determine the type of thermostat that is placed in your home.

Manual

A dial, similar to the one used to set the time on a microwave, will either be in the shape of a dial or will be situated on top of a manual thermostat.

These manual thermostats are only found in older buildings and are no longer widely used.

Programmable

If your thermostat has a digital display but no associated app, it is most likely a programmed thermostat. There are also a few buttons on the screen that can be used to browse the menu.

Smart

Smart thermostats often have a large, bright display and a few buttons. The majority of its functions are accessible via the companion app, which can be downloaded to a tablet or smartphone.

The thermostat ID card that comes with it contains information about your Honeywell thermostat’s model.

If you don’t have the ID or live in a rental, you can figure out the model number by removing the thermostat from the wall plate.

The majority of Honeywell thermostats may be uninstalled by pulling them out of the wall plate. To see if it will come off, slide or flip it. The model number is mentioned at the back.

Keep in mind that jerks or poor handling can cause your thermostat to malfunction. As a result, if it doesn’t come off easily, don’t meddle with it.

Common Honeywell Thermostat Issues

It is not difficult to troubleshoot a thermostat. The main challenge is determining the ailment. The most common thermostat problems are described below.

The display on your Honeywell thermostat is blank. The following factors are frequently responsible for the display going dark:

Drained batteries
Erratic strength
Disconnect the C-wire by opening the furnace door.

If you have a programmable thermostat, changing the batteries will solve the problem. On the other hand, whether you have a manual or smart thermostat, make sure the power wire is not damaged. Check that the air handler and furnace are turned on (switch turned on) and that the doors to the air handler panels and furnace cabinet are securely closed.

If the problem persists, the thermostat may need to be replaced. Unfortunately, troubleshooting is ineffective in resolving blank display issues.

The HVAC system is not working.

The following are examples of common HVAC issues:

When the heat is turned on, it emits chilly air.
The computer will not respond.

Before you worry that your HVAC system is faulty, ensure that your thermostat is set to “cold” or “hot” depending on the temperature. It would be excellent if you left it on.

Also, when setting the temperature, make sure it is either greater or lower than the room temperature.

Furthermore, if the furnace cabinet doors, air handler doors, or panels are left open, the HVAC system is rendered ineffective.

If the previously mentioned repairs do not work, the circuit breaker may need to be examined and reset. Wait five minutes after the system restarts before starting the compressor.

The words “Cool On” or “Heat On” blink.

The “Cool On” and “Heat On” indicators show which system is active at any given time. If your thermostat is turned off, neither of the indicators will appear.

Don’t panic if the “Cool On” or “Heat On” indicator is blinking; your system is on a five-minute delay. This is provided via a compressor protection timer, which is a built-in safety element.

When the power goes out and then comes back on, it prevents the thermostat from short-circuiting.

How to Repair a Broken Honeywell Thermostat

To repair a broken Honeywell thermostat, use the following methods:

Replace the batteries with new ones.

When the batteries are changed, the system settings are normally returned to their initial state, which addresses any difficulties caused by software faults.

The wire connections on all of the thermostats should be severed. While reconnecting, take care not to confuse them.

Remove the device from the wall plate.
After the batteries are removed, five minutes should elapse.
Batteries and wires should both be replaced.
After turning on the system, wait five minutes.
It’s possible that even after replacing the batteries, your Honeywell thermostat will still not work.

Keep an eye out for any power disruptions.

The majority of consumer complaints about thermostats that don’t work properly are usually due to connectivity issues.

Maybe a wire has been severed or the power has been switched off for another cause.

If your Honeywell thermostat system is not working properly, check to ensure that the wiring is intact and that power is being supplied.

Don’t forget to check the furnace cabinet doors and the air handler doors. If either of the openings is not correctly closed, a safety feature incorporated into Honeywell systems activates.

When this option is enabled, the HVAC system becomes inoperable.

Repairing the blinking “Cool On” light

When the “Cool On” light blinks, it usually means that the system is starting up and that the safety timer has tripped to prevent an issue with the thermostat’s compressor.

In this case, you do not need to perform any troubleshooting. The safety feature is automatically off after five minutes.

But, if it does not turn off automatically, you can perform the following:

Set the thermostat to the lowest possible setting. Make sure the fan is also set to automatic.
Check that the thermostat timer is not in setup mode and is turned off.
Check to see if the low battery indicator is turned on.
Check that all of the furnace’s openings are sealed.
Examine the AC filter to see whether it is clogged.
Examine the AC coils for cleanliness.
Reset it by changing the batteries as described above or by selecting the factory reset option from the menu.
Only smart thermostats will be compatible with the latter.

Repairing the flashing “Heat On” light

If the “Heat On” indicator is blinking, the safety timer has been tripped to prevent the compressor in the thermostat from malfunctioning.

In this case, you do not need to perform any troubleshooting. The safety feature is automatically off after five minutes.

But, if it does not turn off automatically, you can perform the following:

Set the thermostat to the lowest possible setting. Make sure the fan is also set to automatic.
Check that the thermostat timer is not in setup mode and is turned off.
Check to see if the low battery indicator is turned on.
Check that all of the furnace’s openings are sealed.
Reset it by changing the batteries as described above or by selecting the factory reset option from the menu.

Only smart thermostats will be compatible with the latter.

Troubleshooting And Diagnostics For Honeywell Thermostat Not Working After Battery Change

There’s a lot to accomplish before you can get the most out of your Honeywell thermostat. Don’t be concerned if you encounter any difficulties. We’ve got your back. In this definitive tutorial, we will go over all of the issues you may encounter while setting it up and tell you how to cope with them.

1. Implement the Proper Battery Type

If you’ve tried replacing the batteries in your Honeywell thermostat but are still having problems, try new batteries. Also, make sure you have the right kind of batteries – make sure they’re suggested ones. Incorrect batteries are a common cause of this gadget not working properly after a battery swap.

Also see Nest Thermostat Isn’t Charging? [Do This Right Now to Repair It]
When selecting the correct batteries for your thermostat, there are several aspects to consider. Checking the interior of the battery compartment is an easy way to achieve this. A 1.5v AA alkaline battery is required for most batteries.

2. Replace All Batteries At Once

Because the charge levels of the old and new batteries may differ, batteries in a thermostat should always be replaced at the same time.

Variations in charge levels can cause your thermostat to display inaccurate temperatures or to stop working entirely.

You should make sure that the replacement batteries have the same charge level as the originals. If not, your thermostat may have trouble recognizing the correct temperature, resulting in strange results in your home.

3. Ensure that the battery is properly installed.

Check that the batteries are properly installed. Take care not to mix up the batteries’ positive and negative ends. This can have an effect on how your thermostat works, causing you to be unable to set the temperature effectively.

To begin replacing the batteries, turn off the electricity to your thermostat. First, remove the old batteries by opening the battery compartment.

Then, with the right polarity, insert two fresh AAA batteries into the container. Finally, turn the thermostat back on and let it do its job.

If you follow the directions, you should insert the batteries such that the + and – marks on the battery correspond to the + and – markings inside the battery compartment.

4. Reset the Thermostat to Factory Settings

You may need to reset your thermostat for a variety of reasons. Strange quirks can arise from time to time, and you may find yourself unable to adjust certain settings. At times, you may want to return to the thermostat’s preset settings.

A factory reset can be performed using either the device’s physical buttons or its web portal. If you utilize one of these ways, however, all of your personal data will be erased.

To reset the thermostat, perform the following steps:

Open the compartment containing the batteries. To open the compartment door, insert your coin or other object into the slot.
Replace the old batteries (follow the polarity markings on the battery holder).
Replace the door and reactivate your thermostat!

Follow these instructions to discover how to reset your thermostat:

Before continuing, remember to switch off your thermostat.
Insert the coin into the slot by sliding it in and then pulling it out, or by pressing down on the coin’s head with a flat item. Then, open the door to the battery box.
Remove the thermostat’s batteries now.
Replace the batteries in the thermostat battery compartment, turning them in the opposite way they were before. The labels on the battery holder will tell you which way is up.
Hold the batteries in this position for five seconds.
Remove the thermostat’s batteries next. Replace them, making sure they are aligned with the correct polarity.
The thermostat display is now illuminated, indicating that it has been turned back on.

Honeywell T5+, T5, and T6 Thermostat Factory Reset

Make sure your thermostat is switched on.
For around fifteen seconds, hold down the Menu button.
Navigate to the Reset option on the left.
Choose Factory Reset by clicking on it.
Press Yes or OK to confirm your selection.
The thermostat has been reset.

5. Wiring Problems

If your thermostat displays an error code, try resetting it to see if the problem goes away. If the problem persists, it could be due to a wiring issue, in which case you should contact a skilled HVAC contractor.

A loose connection, for example, could exist between your thermostat and the wires leading to your wall outlet. A small disconnect could pose a significant problem because you won’t be able to lower the temperature once you begin cooking.

Remove the wires from the wall and make sure the connection is properly linked to both wires. Check that any extra wire is not interfering with other components.

6. Double-check that the door is properly closed.

There is nothing more infuriating than a broken thermostat. Especially if the heater refuses to start on or the thermostat continually turning itself off. This is a simple fix; check your furnace access door and make sure it is completely closed.

7. Examine the circuit breaker/fuse

If your Honeywell thermostat goes out due to a power surge, fuse blowout, or circuit breaker tripping incident, it will not turn back on after changing its batteries unless you replace the blown fuse or reset the relevant circuit breaker in your home.

To begin, open your fuse box and replace the blown fuse with a new one.

How to Reset a Honeywell Thermostat Following Battery Replacement

Let’s have a look at how to reset a thermostat:

Remove the batteries and turn the thermostat to the ‘OFF’ position.
Switch the polarities of the batteries, putting negative (-) on positive (+) and positive (+) on negative (-). (-).
Wait 10 seconds before replacing the batteries in their original locations.
The thermostat will be returned to its original settings.

Final Thoughts

Honeywell thermostat troubleshooting should not be a mystery. It is not difficult to troubleshoot Honeywell thermostats. If you have tested the batteries, wiring, and furnace door but have not found a problem, the thermostat may have a hardware problem or you may not be setting the temperature high enough or low enough.

Use the permanent hold method to ensure that the heating and cooling settings are correct. Simply press the “Switch to Permanent Hold” button while holding down the “Up” or “Down” arrows for heating or cooling.

This will manually adjust the thermostat setting to match the outside temperature. If neither of the preceding options proves successful, you may wish to seek professional assistance.

After replacing the batteries, the Honeywell thermostat will not turn on.

When your Honeywell thermostat stops working, you may believe it is a battery issue. However, before changing the batteries, ensure that they are the correct type and that they are properly inserted. If that fails, attempt a factory reset.