I’m getting heat when calling for air conditioning. Help!

This article applies to all ecobee thermostats except Smart, Smart SI, EMS and EMS SI. 

Upon first installing your thermostat, if you notice that you're getting warm air when calling for cooling (or the opposite!), please check the following:

1) Verify the wiring

Remove the ecobee from the wall and examine the wiring once again. When engaging your compressor, the ecobee will energize the Y1 terminal, so you'll want to make sure you have the correct wire in the Y1 terminal. Verify the correct wiring at your furnace/air handler control board and ensure that the wiring matches at the ecobee.

If you have a heat pump system, please ensure that your O wire is in the O/B terminal and not the W1 terminal--this is a very common mistake. On many other thermostats, the O wire is typically connected to a terminal marked W on one side and O or O/B on the other side; the W is for use with a conventional system (furnace) while O/B is for use with a heat pump. 

If you're not sure whether or not you have a heat pump, here are a few things to consider:

  • Do you have an orange wire in W or O/B? The reversing valve wire is typically orange
  • Do you have any wires in your W2/AUX or E terminals? These terminals engage your auxiliary heat--you will have aux heat if you have a heat pump

Below is an example of what your wiring may look like on your old thermostat. Notice that one side is for conventional systems and one is for heat pumps. While it isn't 100% accurate, if you have a white wire going into a W2/AUX/E terminal, and an orange wire going into a W or O/B, it's a good indicator that you have a heat pump system. 


If you wired up your ecobee system as a conventional system when you actually have a heat pump system, you will just want to make the necessary wiring changes and reconfigure the equipment.

2) For heat pumps, verify the O/B reversing valve is energized on the correct setting

If you have a heat pump system, it's possible that your O/B reversing valve may be energized on the wrong setting. The easiest way to diagnose if this is the issue is by also testing your heat--is the air warm or cool? If the valve is energized on the wrong setting, you'll receive heat when calling for air conditioning and you'll receive air conditioning when calling for heat.

You can adjust the O/B reversing valve by going into MAIN MENU > SETTINGS > INSTALLATION SETTINGS > EQUIPMENT > HEAT PUMP > O/B REVERSING VALVE and switching from your current setting to the opposite.  


If the issue persists, please reach out to our Support team for further assistance. Please have some photos of your wiring handy to help ensure prompt service.

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