Ecobee Thermostat Not Turning On AC? Here’s How To Fix

If the Ecobee thermostat not turning on AC, there’s a quick workaround!

Generally said, the Ecobee thermostat would most often refuse to turn on the AC if the safety switch is flipped or the A/C drain line is clogged.

In this guide, we will provide you with the best-fix methods to troubleshoot your Ecobee thermostat and solve the issue.

To fix an Ecobee thermostat that won’t turn on the AC, make sure the A/C drain line is clean and not clogged. Fix the power income of your connected ACs and power cycle the thermostat. Finally, factory reset your Ecobee thermostat and fix the issue.

Let’s now learn what is preventing your Ecobee thermostat from turning on the AC.

Why Is Ecobee Not Turning On AC?

Chances are that you haven’t chosen appropriate settings from your Ecobee thermostat.

For the HVAC system to boot the ACs, hence, your thermostat, you must choose a heating, cooling, or automatic setting through your thermostat.

Alert: If you haven’t selected any active mods for the system, it won’t boot the AC.

Here are the summarized causes for the problem in a quick list:

1. Wrong Settings

If you’ve disabled the mode from your thermostat for the system, the AC won’t be turned on through the thermostat

2. No Power to AC

The AC is probably connected to the HVAC system, but if no power reaches the device, it won’t be turned on through the thermostat.

3. Problematic Thermostat

There could be an issue with your Ecobee thermostat and its software, preventing you from turning on the AC.

4. Flipped Safety Switch

If you’ve disabled your HVAC system using the safety switch, the ACS will be unbootable with the thermostat.

5. Clogged Drain Line

One of the most often causes of the issue is a clogged drain line of your AC, thus, the device is not getting rid of dirt correctly.

This was what you should know about the issue’s main causes. Now we will provide you with the best fix solutions for you to work with.

How To Fix Ecobee Thermostat Not Turning On AC?

Our solutions are designed for consecutive troubleshooting of the problem.

Make sure that you follow the order of our fix attempts and test turning on your AC after each of the fixes you attempt to determine when the issue would be solved.

Here’s how to fix your Ecobee thermostat that refuses to turn on the AC:

Solution #1 Set Mode For Thermostat

Chances are that your thermostat hasn’t been set to any mode. Keep in mind that the thermostat will only turn the AC whenever it has a schedule of heating/cooling or auto mode to fulfill.

If none of the following mods were chosen, it won’t turn on the AC.

Here’s how to set a mode for your Ecobee thermostat:

1. Go over to your Ecobee thermostat.
2. Open the System tab.
3. Select HVAC.
4. In the following screen, change the setting for HVAC to AUTO.
5. Wait for the AC to be turned on.

Note: You should also attempt choosing a heating or cooling mode for your Ecobee thermostat if AUTO doesn’t turn on the AC.

Solution #2 Power Cycle Ecobee

If setting a mode for your thermostat didn’t work, then the issue is most likely to be somewhere along with the hardware of your HVAC system.

There’s a chance that your thermostat is not getting sufficient charge, therefore it cannot activate the AC.

Here’s how to power cycle your Ecobee in easy steps:

1. On your Ecobee thermostat, take off the front panel.
2. Expose the CR2032 coin-cell battery within the device.
3. Take the battery out of the device.
4. Wait for around 5 minutes with the battery taken out of the thermostat.
5. Re-insert the battery and install the compartment on your thermostat.
6. Test.

Note: Test if the thermostat will turn on the AC now by choosing a mode again. It should happen automatically.

Solution #3 Clean AC Drain

There’s a high chance that your AC’s drain line is clogged and the device is unable to dispose of garbage.

That will prevent the device from working and you will have to clean the drain line to fix the problem with the AC.

Here’s how to clean your AC’s drain line:

1. Go to your AC.
2. Unplug it from the power supply.
3. Check for debris within the drain.
4. Remove any visible dust/debris within the drain line.
5. Grab vinegar and pour it inside the drain line.
6. Take off the drain cap that is holding the drain line’s opening.
7. With a wet or dry vacuum, suck out any debris left inside.

Note: Ensure that the drain line is not clogged before reinstalling the drain cap, thus, the AC can proceed with the disposal.

Solution #4 Disable Safety Switch

Users generally install a safety switch on their HVAC system, to disable the entire system in case of emergency.

The switch in your system could have been accidentally flipped, therefore preventing the entire furnace and ACs from working.

You will want to search for that safety switch inside the furnace compartment of your home. There you will see a pipe coming out of the HVAC system’s furnace, on which is installed the safety switch itself.

Make sure that the safety switch is spun towards the OFF label, marked on its hardware.

Note: Safety switches are generally harder to turn OFF/ON, due to their anti-children mechanism. Apply force if necessary.

Solution #5 Reset Ecobee Thermostat

If none of our solutions were of your assistance, the last thing you should do is to perform a factory reset on your Ecobee thermostat.

That will wipe out the entire software settings and configurations of the device, regarding the ACS and HVAC system itself.

Here’s how to reset your Ecobee thermostat in easy steps:

1. On your thermostat, press the Menu button from the home screen.
2. Select settings.
3. Go to Reset.
4. Tap on “Reset All Settings”.
5. Confirm by pressing Yes on one following screen.
6. Erase the entire software by choosing the reset type.
7. Wait and then test.

Note: You will have to renew the configurations, modes, schedules, and AUTO-preferences once your thermostat is done resetting itself.

Ecobee Thermostat Still Not Turning ON AC…

In case you’ve attempted all of our solutions and your AC still is not turning on, the next best step would be to check if your warranty is still intact.

This way you can reach out to Ecobee and demand a replacement, which you’ll most likely receive.

However, if you’re unable to use the warranty, you may still want to contact Ecobee to provide you with the next steps in regard to solving the problem.

Thus, to fix an Ecobee thermostat that won’t start the AC, power cycle the AC and thermostat first. Clean the drain line of the AC and ensure that the safety switch is disabled. At last, the factory reset your Ecobee thermostat to solve the issue.

Read Next: How to Fix Ecobee Thermostat No Power?

Bottom Line:

Now that you’ve learned why the Ecobee thermostat not turning on AC and is fully capable of troubleshooting thermostat-related problems, the rest is up to you.

Perhaps if the issue wasn’t solved by now, your thermostat or AC might be due for replacement.