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Thermo Fisher Scientific

Condensation around the door frame


There is condensation around the door frame


TSX Laboratory Refrigerators TSX -20° Laboratory and Enzyme Freezers TSX -30° Plasma Freezers  Model Energy Star Model
TSX1205G TSX2320F TSX1230L V/Y/Z A/D
TSX1205S TSX3020F TSX2330L V/Y/Z A/D
TSX1205P TSX2320E TSX3030L V/Y/Z A/D
TSX2305G TSX3020E TSX5030L V/Y/Z A/D
TSX2305S     V/Y/Z A/D
TSX2305P     V/Y/Z A/D
TSX2305C     V/Y/Z A/D
TSX3005G     V/Y/Z A/D
TSX3005S     V/Y/Z A/D
TSX3005P     V/Y/Z A/D
TSX3005C     V/Y/Z A/D
TSX4505G     V/Y/Z A/D
TSX4505C     V/Y/Z A/D
TSX5005G     V/Y/Z A/D
TSX5005S     V/Y/Z A/D
TSX5005P     V/Y/Z A/D
TSX5005C     V/Y/Z A/D


Troubleshoot Perimeter Heater Duty Cycle
  • Increase the Perimeter Heater Duty Cycle:
  1. You can enter the service mode by pressing the Scan button (SCAN) and holding for approximately 10 seconds while in Programming mode.
  2. The display will then flash “SEr” to indicate that you have entered the service mode followed by the software checksum values flashing on the screen. The service icon will also illuminate.
  3. Use up (+) and down (-) buttons to modify the values and press the scan (SCAN) button to save the value and go to the next screen.

Note: If the alarms are enabled, the unit will not enter Service Mode.

Check port holes
  • Ensure all port holes in the cabinet top, sides, and back are sealed properly to prevent warm airflow into the cabinet. Seal any gaps.
Verify nothing is placed through the door seal such as a sensor
Check the door seal
  1. Open the door.
  2. Insert a strip of paper (a couple of inches wide) between the door gasket and the cabinet flange and close the door.
  3. Slowly pull the paper strip from the outside. You should feel some resistance.
  4. Repeat this test at 4-inch intervals around the door. If the door does not seal properly, replace the gasket.


The possible causes of this issue include:

  • Incorrect perimeter heater duty cycle may be running
  • Gaps could possibly exist in the unit port holes
  • The door seal could be broken