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Thermo Fisher Scientific

Temperature malfunctions


ULT unit may be experiencing any of the following:

  • Unit warming.
  • Unit set to –80°C but can’t make temperature(Not reaching setpoint).
  • Unit recovers slowly to set point. 


TSX Ultra Low Temperature (ULT) Series:

Thermo Scientific – TSX40086A
Thermo Scientific – TSX40086D
Thermo Scientific – TSX40086V
Thermo Scientific – TSX40086G
Thermo Scientific – TSX50086A
Thermo Scientific – TSX50086D
Thermo Scientific – TSX50086V
Thermo Scientific – TSX50086G
Thermo Scientific – TSX60086A
Thermo Scientific – TSX60086D
Thermo Scientific – TSX60086V
Thermo Scientific – TSX60086G
Thermo Scientific – TSX70086A
Thermo Scientific – TSX70086D
Thermo Scientific – TSX70086V
Thermo Scientific – TSX70086G


Possible Causes and Solutions:

  1. Cause : Warm load / Over load.
    Solution: Allow ample time to recover from loading warm product. Do not overload cabinet.

  2. Cause: Hot environment. 
    Solution: Check, if the location meets ambient requirements (within 15°C to 32°C or 59°F to 90°F) and away from hot objects.

  3. Cause: Dirty condenser and condenser filter. 
    Solution: Clean condenser and filter.

  4. Cause: Not enough space for air circulation. 
    Solution: Install the unit in a level area free from vibration with a minimum of 8 inch (20 cm) of space on the top and sides, 6 inch (15 cm) in back.

  5. Cause: Icing/Frost due to high relative humidity. 
    Solution: Check if the location meets requirements. Maximum relative humidity 60% for temperatures within 15°C to 32°C (59°F to 90°F). 

  6. Cause: Excess frost build-up in chamber. 
    Solution: Defrost the unit.

  7. Cause: Frost build-up on outer door gasket. 
    Solution: Occasionally scrape the ice on the gasket.

  8. Cause: Gasket damage.
    Solution: Check for punctures or tears on gasket. Replace if necessary.

  9. Cause: Prolonged door openings.
    Solution: Avoid opening of door for longer duration. Allow ample time for recovery after door opening. 

  10. Cause: Inadequate power supply.
    Solution: Check for proper voltage to the unit.

Call Service if either one of the compressors are not working and/or if refrigerant is insufficient.