What does an "LO" reading on screen mean?
* The floor sensing probe is damaged, missing or loose.
* Call your electrician.
What does an "HI" reading on screen mean?
The floor sensing probe is reading a temperature over 104F.Probe is likely too close or is touching a heating wire inside the mat.The probe must be relocated. Call your tile setter to reposition the sensor.
Since your thermostat is not displaying the above I would say your sensor is good also...
Opps, sorry, that was for Nu-heat, not easy heat...