Honeywell Thermostat Heat Not Working On Auto: How to Fix

Worried about your Honeywell thermostat heat not working on auto? I get that!

In this post, I’ll walk you through some troubleshooting steps that may help you fix a Honeywell thermostat with this problem.

However, keep in mind that most problems with the thermostat heat not working on auto may require an HVAC expert to check the entire system and you may even have to replace the thermostat.

But don’t fret. The troubleshooting tips below may help you fix your malfunctioning thermostat.

Honeywell Thermostat Heat Not Working On Auto

Honeywell Thermostat Heat Not Working on Auto: How to Fix the Problem

1. Check All the Wires

The first and probably the only DIY step is to check that the wires back there are okay. Damaged or short wires are the most common cause of this issue. So, pull the thermostat off of the wall and check the wires.

Check every single wire back there and look out for any short or damaged wire. Also, twist the G wire, R wire, and W wire together to ensure nothing is wrong with them.

If you think there is nothing wrong with the wires—everything intact and looks good, you may need to seek professional help to resolve the issue. See the next step.

2. Contact Honeywell Support Team or an HVAC professional

Assuming you are sure the fault is not from the wires, the next thing is to contact the support team. Honeywell sure has experienced professionals who handle this kind of situation all day.

However, when speaking with a representative, make sure you mention everything about the issue. That will help them know what exactly to do to get your thermostat back on track.

On the one hand, you may want to call an HVAC professional near you to quickly resolve the issue. As mentioned, an HVAC expert would check the whole thermostat (including the furnace) to understand what really went wrong.

3. Replace Your Thermostat If It’s Faulty

Though it’s sometimes hard to accept, the reason your Honeywell thermostats won’t work on auto is that the thermostat is faulty and due for replacement. So if the above steps couldn’t fix your thermostat, then it might just be time to replace the device.

Get a new one or newer model (if your present model is outdated) to enjoy all the fantastic features the thermostat offers, including controlling room temperature on auto.

Related Problems and Troubleshooting Tips

Why is my thermostat not turning the heat on?

It is not uncommon to experience your Honeywell thermostat not turning on the heat. To fix this, follow these steps:

  1. Check to be sure the switch is set on “Heat” and not on “Cool.”
  2. Open the thermostat and gently blow out dust and debris.
  3. Check the wires to see if any of them is loose.
  4. Make sure the thermostat is level and firmly attached to the wall.

Why is my furnace blowing cold air when the heat is on?

One common cause of this is when the filter is too dirty. This may cause the furnace to blow cold air even when the heat is on. How? A dirty heater causes the heat exchanger of the furnace to become blocked, causing it to overheat. This prevents the pilot light from lighting, therefore preventing it from making any heat.

Closing Thoughts

There may be several reasons your Honeywell thermostat heat doesn’t work on auto. This includes loose or damaged wires or a faulty blower. It could also mean that your thermostat is due for replacement.

But before you conclude, you want to contact Honeywell or get an experienced HVAC expert to have a look at it and tell you what next to do!


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