Annual Calibration; Battery Replacement; Door Gasket And Vacuum Relief Port; Defrost - LabRepCo GM-ULT-1786 Owner's Manual

Annual calibration

The control temperature probe should be calibrated once a year. This procedure is described in
the Maintenance Procedures chapter under Calibration.

Battery replacement

Warning! Only authorized, trained electricians should attempt any access behind
the service panels!
The battery is located in the lower left-hand (handle side) corner of the compressor
compartment. It may be accessed by either removing the front or left-side cover panel. The
battery is secured with two carriage bolts, but it is only necessary to loosen one bolt to remove
the battery.
Be sure to disconnect the leads from the control box before removing the battery.

Door gasket and vacuum relief port

Any time that dirt or frost accumulation prevents the door from closing properly, the gasket
should be cleaned with a soft cloth. As a general rule, a minimum of once a month is
recommended.
When the door gasket is operating as designed, the only means of pressure equalization for the
chamber is the vacuum relief port behind the control panel. The vacuum relief port is equipped
with a built-in heater to reduce frost accumulation, but some frost can accumulate behind the
port on the freezer door. It is important to make a visual check for such accumulation whenever
the door is opened and remove any accumulation found.

Defrost

1. Switch off the unit breaker switch and disconnect the freezer from power.
DISCONNECT battery to avoid deep discharge. To disable the battery, scroll to the
CONFIGURE MODE and press ENTER. Scroll to BATTERY BACK-UP ON, and press
ENTER
Use the UP and DOWN keys to change to OFF, then press ENTER. Upon restart, this
configuration will automatically revert to the ON setting
Part number 21729, Rev 4
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