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Ecobee Not Showing Cool Option? Here’s How to Fix It

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🌡️If your Ecobee thermostat is missing the Cool mode from its options, it can be confusing and frustrating—especially during hot weather. Fortunately, this is usually a setup or wiring issue that can be resolved with a few simple steps.

In this guide, we’ll walk you through the most common reasons why the cooling option is missing and how to troubleshoot and fix it.

đź’ˇ Why the Cool Option Might Be Missing

When Ecobee doesn’t detect a cooling wire during setup, it assumes your HVAC system doesn’t support air conditioning. That’s why the cool mode won’t appear in the thermostat’s menu.

The most likely causes are:

  • Incorrect wiring (especially the Y1 wire)
  • Incorrect configuration during installation
  • HVAC system issues or disconnected wires at the furnace

🔍 Step-by-Step Troubleshooting

Check Your HVAC System for AC Capability

First, confirm that your HVAC system actually includes air conditioning. Some homes only have heat.

  • Look outside for a central AC unit
  • If it exists, the system should be capable of cooling

If you do have AC, continue with the following steps.

Verify Wiring at the Thermostat

The Y1 wire is responsible for cooling. If it’s not detected or properly connected, Ecobee won’t show the cooling option.

  1. Turn off power to your HVAC system at the breaker
  2. Remove the Ecobee faceplate
  3. Check that the Y1 wire is securely inserted in the terminal
  4. Make sure the wire is straight and making solid contact with the terminal plate

If there’s no Y1 wire, cooling cannot be enabled.

Inspect the Furnace or Air Handler Wiring

Even if the wiring looks correct at the thermostat, it’s possible that the Y1 wire is disconnected or loose at the furnace end.

  1. Remove the cover of your furnace control board
  2. Find the Y terminal on the board
  3. Ensure the wire is attached and secure

If disconnected, reattach it, then restore power to the system.

Reconfigure the Equipment Settings

If the Y1 wire is present and connected properly, you may need to manually reconfigure your equipment settings.

  1. Go to Menu > Settings > Installation Settings > Equipment
  2. Tap Reconfigure Equipment
  3. Follow the prompts to identify your HVAC system
  4. Ensure you select Cool when asked which functions your system supports

After setup is complete, check if the Cool option appears.

Reset the Thermostat (if needed)

Sometimes a full reset is necessary to clear out old configurations.

  1. Go to Menu > Settings > Reset > Reset All Settings
  2. Follow the instructions to reinstall and reconfigure the thermostat

Make sure to identify cooling as a supported function during the walkthrough.

Contact Ecobee Support or a Pro

If all wires are correctly connected and you’ve reconfigured the system but still don’t see the Cool option, the issue might be deeper:

  • Y1 wire is broken or damaged inside the wall
  • Control board malfunction
  • Software bug or firmware issue

Contact Ecobee support or hire an HVAC technician to inspect and test your system.

âś… Final Thoughts

If your Ecobee thermostat isn’t showing the Cool option, the issue is almost always related to wiring or setup. Begin by confirming that your HVAC system supports cooling, then check the Y1 wire at both the thermostat and furnace. With a quick reconfiguration or reset, your Ecobee should be back in cooling mode in no time.