Manual
USER GUIDE
Thermistor 1
u-line.com
SAFETY • INSTALLATION & INTEGRATION • OPERATING INSTRUCTIONS • MAINTENANCE • SERVICE
Thermistors
Thermistors are used for various temperature readings. 
Thermistors provide reliable temperature readings using a 
resistance which varies based on surrounding 
temperatures. If a faulty thermistor is suspected it may 
be tested using an accurate ohmmeter.
All thermistors in the unit are identical. If a thermistor is 
suspected of being defective the resistance can be 
verified. Place the thermistor in an ice water bath, the 
resistance should read 16.1k OHMs +/-5% on your meter.
Thermistor connections must be kept clean. A thermistor 
connection that has become corroded can cause 
resistance values from the thermistor to change as they 
pass through a dirty connection to the board. 
It is for that reason that we apply dielectric grease to all of 
our thermistor connections. Dielectric grease will help to 
keep thermistor connections clean and dry. 
If you change a thermistor in the unit please re-apply 
dielectric grease to the connection. If you encounter a 
dirty thermistor connection, you should replace the 
thermistor and the thermistor harness.
Thermistor error information can be found in the Control 
Operations - Service section.
This unit has three thermistors.
Thermistor one (Zone):
Located along the right hand side wall. It is used to 
maintain the operating temperature within that zone.
Thermistor two (Evaporator):
Located on the evaporator. It is used for defrost.
Thermistor three (Ambient):
Located in the base of the unit (secured to the 
condenser). It is used to monitor the ambient temperature 
within the base compartment. It is used for diagnostics.
THERMISTOR FAILURE
Zone Thermistors
If a zone thermistor(s) in the unit fails the unit will 
continue to cool in a backup mode (Self Preservation 
Mode) to preserve the integrity of the contents. The unit 
will otherwise operate normally.
2000 Series Self Preservation Mode:
The unit will cycle on for 10 minutes then off for 40 
minutes.
3000 Series Self Preservation Mode:
Cycle times determined by zone - see chart. The error will 
be displayed on the main display, “Self Test” and logged in 
“All Errors.”
Self Preservation Mode Data Table - 3000 Series
Evaporator Thermistors
If an evaporator thermistor fails the unit will rely on a 
preset defrost timer during defrost cycles. The unit will 
otherwise operate normally. Refer to defrost section.
Ambient Thermistor
If the thermistor fails the unit will operate normally.
Mode ON OFF
Beverage/Drinks 10 45
Market/Fresh 10 45
Root 5 90
Pantry 10 45
Deli 10 45
White Wine 5 60
Red Wine 5 60
Sparkling Wine 10 60
Polar 55 5










