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How to Resolve the ER2 Message on the Terra Smart WiFi Thermostat?

When the thermostat reads “ER2,” the floor sensor has a short circuit or has a loose connection. Your electrician must secure connections and test the probe using a multimeter set to the lowest possible ohms scale. The resistance reading should be between 7 and 17 ohms.  If a short is found and a backup sensor probe was not installed, you can bypass the error message by setting the thermostat to read the air temperature instead.

If you would like to resolve the ER2 Message on the Terra Smart WiFi Thermostat, watch the video, or read the short or long format instructions down below:

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Short format instructions for Resolving the ER2 Message:

  • Press accept to continue
  • Use the arrows to move to the settings icon and press accept
  • Use the arrows to move to the thermostat application icon and press accept.

  • 1 means Floor Sensor and 2 means Air Sensor

The thermometer icon represents the “control” sensor. The shield icon represents the “limit” sensor. If shown on your thermostat in this order, the control sensor is set to floor and the limit sensor is set to air. If reversed, the control sensor is set to air and the limit sensor is set to floor.

  • Make your selection and press accept
  • Refer to the chart below for the next step

  • Move to your preference based on the chart above and press accept
  • Next, utilize the Wiring Connection chart below

  • Move to your temperature format preference and press accept
  • Continue to press the “X” to return to the home screen

Full Instructions for Resolving the ER2 Message:

In order to resolve the ER2 Message, follow the steps outlined below. Please note that the following instructions assume you are using a Warmup Terra Smart WiFi Thermostat. If you see an !ER2 Message appear on your thermostat screen in red lettering, follow these instructions to help resolve this message from appearing.

First action to take is to press “accept,” which is also known as the check mark icon. Next, utilize the arrow buttons to navigate to the Settings icon, and then press “accept” to open the thermostat application. The Settings icon is represented by a gear icon. The thermostat application is represented by a thermometer icon.

After clicking on the thermostat application, you should now see a shield and thermometer icon. If you see the thermometer icon followed by the shield icon on your thermostat, it means that the control sensor is currently set to the floor sensor, and the limit sensor is set to the air sensor. If the order is reversed, the control sensor is set to the air sensor, and the limit sensor is set to the floor sensor.

The thermostat icon is also represented as the “control” sensor, while the shield icon is represented as the “limit” sensor.

In the example to the left, 1 means Floor Sensor, and 2 means Air Sensor.

Make your desired selection based on this information and press “accept” to confirm.

Refer to the chart below for the next step:

View the Thermostat Use Case Chart to the left.

Move to your preferred option as indicated in the chart above, and press “accept.”

Next, consult the Wiring Connection Chart provided below:

View the Wiring Connection Chart Diagram to the left.

Use the arrow buttons on your thermostat to navigate and find your desired temperature format preference, and press “accept” to confirm your selection.

To return back to the home screen, simply press the “X” button repeatedly until you reach the home screen.

For future reference, the charts provided are located in the Terra Instruction Manual.

If you are experiencing any difficulties or encountering any issues while attempting to resolve the !ER2 Message from your Terra Smart WiFi Thermostat, rest assured that we are here to assist you. Our dedicated support team is ready to provide you with the necessary assistance to resolve any problems you may be facing.

To access our support services, simply reach out to us at 888-927-6333.


Further Questions?