Why Is My Honeywell Thermostat Heat Not Working On Auto?

If your Honeywell thermostat heat not working on auto, you’ve come to the right place.

There are a lot of possibilities that can impact the auto features but luckily there are twice as many solutions against them.

By the end of this guide, you’ll be familiar with what might be causing the problem and how to effectively troubleshoot!

If your Honeywell thermostat does not enable the heating on auto, there are most likely loose connections or power issues with the thermostat itself. Your thermostat’s battery could be running low, the sensor might be not working or simply the feature is not enabled.

This is just a small fraction of all possibilities and next, we’re about to cover them all!

Why Honeywell House Thermostat Heat Not Working On Auto?

Users rarely have issues with the auto mode on their Honeywell thermostat, but the ones that do report this problem, often share the reason is a not working blower.

Make sure to check if your blower is working at all because if it isn’t, the automatic heating will stop due to overheating.

Let’s exclude the blower as a possibility for now and take a look at the most frequent issues that can be easily resolved at home:

1. Low Battery

A low battery might also prevent your thermostat from running on auto, so you will have to charge it.

2. Config Problem

It is possible that you’re thinking you have enabled the auto mode correctly, but it is actually disabled.

3. Wiring Problem

In case the position of your thermostat has been damaging the cables over time you’ll be observing not only auto feature problems but overall function inability.

4. Data Problem

Lastly, corrupted data might also greatly impact your thermostat’s firmware and prevent you from using any of the features the thermostat offers.

5. Hardware Blower Issue

In some cases, the blower will not turn on automatically and the heating will be stopped due to overheating.

After mentioning the essentials of the issue, we may proceed with the best solutions recommended by users that have the same issue as you do!

How To Fix Honeywell Thermostat Head Not Working On Auto?

Now that you know the main suspects, we suggest trying to restart your thermostat first.

Sometimes all it takes is a simple restart to get things going, so make sure to try that before proceeding with our solutions.

If the reboot did not fix the auto feature, then let’s start applying the solutions:

Solution #1 Turn On The Heating

If your thermostat’s heat isn’t working on auto, then you most certainly haven’t chosen the “heat” option in the thermostat’s menu.

You will be able to find the “heat” feature in the thermostat’s menu, where you set up the auto settings.

Keep in mind that the auto settings will be initiating the current configurations you’ve chosen for your thermostat.

If you haven’t chosen to heat in the menu, your thermostat won’t be heating, thus giving the impression that the auto feature is not working.

Solution #2 Program The Thermostat

If your Honeywell thermostat is programmable, then you must make sure that it is programmed correctly for the temperature you desire for it to work on.

At the specific time of the day, you must have programmed your thermostat to work in “heating” mode, or otherwise, the auto feature won’t work as intended.

Here is how to correctly program a Honeywell thermostat:

1. Go to your thermostat’ settings.
2. Access the auto menu and go to the day configuration.
3. Set a specific interval of the day and choose “heating”.

From now on, your thermostat will automatically enable “heating” mode, during the time of the day you have set.

Solution #3 Troubleshoot Wires

If the issue is not related to your thermostat’s programming, users suggest that you take a look at your thermostat’s wirings.

Alert: In order to avoid potential injury, flip off the thermostat’s power while reviewing the wirings.

We recommend unplugging ALL cables and reconnecting them back in their places. The standard approach would be yellow is cooling, red is power, white is heat and green is the blower.

Take a close inspection of the green cable responsible for the blower, and make sure that it is plugged in tightly!

Solution #4 Enable “Fan Auto” Feature

If you’ve left the “Fan Auto” feature disabled, then this means your thermostat’s fan won’t go working by itself when it is supposed to.

This can lead up to some serious internal damage to your heating/cooling system and might sometimes prevent your thermostat from working as well.

We suggest enabling the feature by going into the settings of your thermostat and flipping it on in the Auto menu.

Once it is on, reboot your thermostat in order for the feature to take effect, and then try the auto-mode again.

Note: Keep in mind that this feature always requires an active charge in your thermostat. In that regard, you must ensure that your thermostat always has a charge.

Solution #5 Reset Your Honeywell Thermostat

If nothing worked, then perhaps the auto feature glitched and you will have to reset your thermostat in order for it to work.

Keep in mind that other heating/cooling daily routines will be erased once you initiate the reset, so make sure to remember any features you would have to reapply later.

To reset your thermostat, follow these steps:

1. Turn OFF your thermostat.
2. Locate the HVAC breaker inside the panel of your thermostat.
3. Turn the breaker and wait for 30 seconds before turning it back.
4. Power on your thermostat.

Now go to the auto menu and re-enable the feature. Create a test routine to determine whether the heating is going to be functional now or not.

Solution #6 Inspect Limit Control

If by now the issue is not solved, there is a pretty efficient way to quickly realize which part prevents the automatic heating.

You’ll now observe each part of the sequence in action and depending on what does not start you’ll know what to replace.

Alert: Be extremely precise with the steps and make sure NOT to touch any wires, otherwise you might get shocked.

Also, make sure NOT to touch or twist the round dial.

Here is how to find out which part does not work:

1. Open the front furnace door to view the controls.
2. Locate the fan limit switch (in most cases in the bottom left corner, it looks like a white cylindrical-shaped button).
3. Turn the heat all the way up!
4. The burner should start.
5. The limit control dial should start rotating.
6. The blower should start.

If it’s only the AUTO function that does not work, it’s most probably that the blower does not start meaning that there is an issue with the temperature sensor.

If you can confirm that when directly looking at the controls, then you’ll need to bring the thermostat for a repair.

Read Next: Why Does My Honeywell Thermostat Keeps Shutting Off?

Bottom Line:

To fix a Honeywell thermostat with not working auto-mode, first, reboot the device and check if the heating is enabled. Next, enable the fan auto feature and if it does not work, proceed with a factory reset.

Now that you know why Honeywell thermostat heat not working, you should be able to easily fix the issue following our easy solutions.

If you struggle at some point, it is always a reasonable option to contact Honeywell and get this case unveiled with the assistance of a dedicated engineer.