UniMac Industrial Washer Error Code Open Temperature Sensor Error
Open Temperature Sensor Error means the UniLinc control reads below 5 F on a machine with a temperature sensor, which indicates an open thermistor. The cycle is aborted with an audio alarm and a log entry. Clear the menu and return to the Cycle Menu.
Medium: the cycle is aborted, and hot cycles cannot run until the sensor is repaired.
- Code
- Open Temperature Sensor Error
- Maker
- UniMac
- Equipment
- Industrial laundry
- Applies to
- UniLinc control pocket hardmount washer-extractor (UW35-UW150, 2009-2012 manuals)
What does UniMac Open Temperature Sensor Error mean?
On machines with a temperature sensor, the control reads a thermistor. A thermistor that has gone open circuit reads as an impossibly low temperature, and the control treats anything below 5 F as open. When it sees that, it aborts the cycle, shows the Cycle Aborted Error Menu with Open Temperature Sensor Error, sounds the audio alarm and logs the event. The manual's only operator action is to clear the menu and return to the Cycle Menu. The reading is not a real cold wash: it means the signal wire or the sensor is broken. Typical reasons are a sensor cable that has been pulled or pinched, a connector that has worked loose, or a thermistor that has failed. The opposite case is reported as Shorted Temperature Sensor Error. Since a hot cycle cannot be controlled without a trustworthy reading, the control stops instead of guessing.
Affected models and control systems
UniMac UniLinc control on the UW35TV, UW60TV, UW80TV, UW100TV, UW125TV and UW150TV washer-extractors and the UWL, UWN and UWU 035-150 T3 models.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- Open Temperature Sensor Error on the display
- Audio alarm
- Cycle aborted
- Temperature display absurdly low or blank
Possible causes
Likely causes — what usually sits behind Open Temperature Sensor Error on this control. A technician confirms which one it is before any part is replaced.
- Thermistor open circuit
- Sensor cable broken or pinched
- Connector loose at the sensor or the control
- Control input not reading the thermistor
Safe checks before calling for service
- Clear the Cycle Aborted Error Menu and return to the Cycle Menu.
- Do not restart hot cycles repeatedly.
- Run a cold cycle only if the site allows it and no sensor is needed.
- Check for water leaking near the sensor.
- Tell the technician the cycle and step where the error appeared.
How a technician diagnoses Open Temperature Sensor Error
- Read the log and the cycle step.
- Measure the thermistor resistance with power off and compare it with temperature.
- Inspect the cable and connector for breaks.
- Test the control input with a resistor of known value.
- Replace the thermistor or cable and run a test cycle.
- The sensor wiring runs into the line-voltage electrical area.
- A thermistor must be tested with a meter and a reference.
- Replacement involves parts in a wet section of the machine.
How Open Temperature Sensor Error differs from similar codes
Open Temperature Sensor Error reads below 5 F. Shorted Temperature Sensor Error reads above 220 F.
Technical reference
- Maker documentation
- UniMac owner support
- Edition
- Part No. F8138801R3, September 2009
- Models / control
- UniLinc control pocket hardmount washer-extractor (UW35-UW150, 2009-2012 manuals)
- Section
- Diagnostic: Machine Errors (pp. 56-59)
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related UniMac industrial laundry error codes
Is the water really that cold?
No. A reading below 5 F means the thermistor circuit is open.
Can I wash cold?
Only if the cycle does not need the sensor, and not as a fix.
What is the opposite error?
Shorted Temperature Sensor Error, for a reading above 220 F.
Need help with UniMac Open Temperature Sensor Error?
A technician confirms the cause on site and gives you the price in writing before any work starts.