vwr.com I Instruction manual VWR
®
ULT Freezer 352/528 Eco Premium 02/2022
Page 56/86
15.4.5 Messages referring to temperature sensor failure
The alarms occur immediately.
•
Audible alarm (buzzer)
•
Switching the zero-voltage relay alarm output
Failure of the temperature sensor for interior measurement:
•
Alarm message “Inner temp. sensor”, collective alarm icon
•
Cause: defective inner temperature sensor
•
Temperature control continues using the safety controller temperature sensor
Failure of the safety controller temperature sensor:
•
Alarm message “Safety control sensor”, collective alarm icon
•
Cause: defective safety controller temperature sensor
Failure of both the temperature sensors for interior measurement and the safety controller:
•
Temperature display shows “- - - -” or “<-<-<” or “>->->”
•
Alarm messages “Inner temp. sensor” and “Safety control sensor” alternating, collective alarm icon
•
Cause: both the temperature sensors for interior measurement and the safety controller are defective
•
Refrigeration is turned on permanently.
Failure of temperature sensors of the refrigerating machine:
•
Alarm message “Condensate temp. sensor”, collective alarm icon
Cause: defective temperature sensor on the condenser of the refrigerating machine
•
Alarm message “Cascade temp. sensor”, collective alarm icon
Cause: defective temperature sensor on the cascade of the refrigerating machine
If this sensor fails, refrigeration is turned on permanently.
•
Alarm message “Ambient temp. sensor”, collective alarm icon
Cause: defective temperature sensor for ambient temperature or air intake of the 1
st
stage cooling
Actions:
•
Please contact Avantor Services.
•
If the temperature rises, i.e. the refrigerating machine is defective (safety controller temperature alarm
and / or tolerance range alarm):
•
Transfer the material to another freezer.
•
Turn off the freezer.
•
If necessary, clean and disinfect the freezer.