Helmer Scientific i.Series
®
Ultra-Low Freezer
Service and Maintenance Manual
360173-A/C
25
Defrost and Clean Chamber
WARNING
Do not use a secondary heat source to defrost the freezer. The use of an electrical heat source (such as a heat gun) could
create an electrocution hazard if the user comes into contact with water from the defrosted chamber.
CAUTION
• Use appropriate gloves when handling cold interior components and stored inventory.
• Keep hands away from pinch points when closing the door.
• Defrosting the freezer will create excessive water in the work area. Take necessary precautions to prevent slip hazards.
NOTICE
• Before defrosting chamber, protect items in freezer from extended exposure to adverse temperature.
• Do not use a secondary heat source to defrost the freezer. The use of a secondary heat source (such as a heat gun) may
create additional pressure within the refrigeration system and may damage system components.
• Allow chamber temperature to stabilize at setpoint before moving product back into the freezer.
Note
All moisture must be removed before powering the freezer on. Any remaining moisture will re-freeze in the chamber and may
require more frequent defrosting than indicated in the preventive maintenance schedule.
Defrost the chamber
1. Move stored product to an equivalent freezer.
2. Switch back-up battery ON/OFF switch
OFF
; switch AC ON/OFF switch
OFF
; and disconnect the AC power cord from the
power receptacle and remove from freezer.
3.
Move the freezer to a location where water can be captured as the chamber thaws, preferably close to a floor drain.
4. Open the chamber door. Prop the door open, ensuring the method used does not damage the door gasket.
5. Remove and defrost the interior doors.
6. Allow the freezer to set for 24 hours to allow accumulated frost to melt. After 24 hours, check to verify that the interior is free
of frost.
7. Clean interior surfaces and door gasket with soft cotton cloth and non-abrasive liquid cleaner.
8. Wipe the interior surfaces and door gaskets with a dry cotton cloth to remove moisture.
9. Reinstall the interior doors.
10. Close the chamber door.
11.
Remove any accumulated moisture from the floor.
12. Move the freezer to the original location.
13. Reattach the AC power cord to the freezer.
14. Reconnect the AC power cord into the power receptacle; switch AC ON/OFF switch
ON
;
and switch back-up battery ON/OFF
switch
ON
.
15. Touch
Mute
to disable the high temperature alarm while freezer reaches operating temperature.
16. Once the freezer reaches the setpoint it is ready for use.
17. Return stored product to the freezer.
Defrost and Clean Exterior Door Gasket
If the exterior door gasket has excessive frost or ice build-up and requires defrosting, Helmer recommends defrosting the entire
chamber. After defrost is complete, carefully inspect the door gasket for tears or damage, and ensure proper adhesion to the exterior
door.
