3iE Energy-Monitoring Thermostat

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What does “ER1” on the thermostat display mean?


When the thermostat displays an ER1 message, make sure that the floor sensor is connected to the correct terminals at the back of the thermostat and has not come loose.

If the floor sensor is in the correct terminals, an electrician will need to check the resistance of the floor sensor using a multimeter set to 20k Ohms to check for floor sensor damage. A fault is indicated when the reading on the sensor is incorrect.

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There is another reason this error message will display. The floor sensor lacks connection to the thermostat. Your electrician must secure the sensor probe wires are connected in ports 1 and 2 of the thermostat. Program your thermostat to read the air temperature instead, by following the steps below:

3iE: Menu > Settings > Set Heating Target > Target Air Temperature

4iE: Menu > Settings > Heating Preference > Control/Air Floor > Air > Accept

6iE: Menu > Settings > Advanced Settings > Sensors and Application > Toggle both probes to the off position

With Wi-Fi thermostats, change your settings online via the My.Warmup.com account.

Related questions:

How do I test a floor probe?

Will the Electric Floor Heating System Work Without the Floor Sensor Probe?