Understand sensorless regulation and its lack of floor overheat protection on the UTN5 nTrust 2.0 thermostat.
Sensorless mode on the UTN5 nTrust 2.0 regulates heating by a fixed percentage of the operating cycle instead of measuring room or floor temperature. It is selected during the initial setup wizard.
For example, a display value of 75 means that heating is enabled for 75% of the cycle. The display shows a percentage, not a measured temperature. The manual suggests 20–25% as an initial setting, but this is not a floor-temperature limit.
Floor overheat protection is disabled in sensorless mode. Internal overheating protection for the thermostat itself remains active. The heating indicator lights only while heat is being delivered.
Have the installer confirm that sensorless operation is suitable for the heating system and flooring before selecting it. Do not use it to bypass a required floor-temperature limit. A sensor error still needs investigation; selecting a different control mode does not repair a defective sensor.
Sources
- Manufacturer instructions (publication 13191), PDF pp. 8–9.