Thermo Scientific CryoStar NX50, Operator'S Manual

Page: 85 / 126

4 - Operation
75
Defrost
Inevitably, when working on the microtome the dry cold air of the cryo chamber mixes with the warm humid air
outside the chamber. Frost forms on the finned evaporator. The increasing thickness of the frost reduces the
efficiency of the evaporator. For this reason, the daily defrosting is necessary.
WARNING: D
URING DEFROSTING
,
REMOVE THE SPECIMENS FROM THE CRYO CHAMBER
,
AS
THE TEMPERATURE INSIDE THE CHAMBER WILL INCREASE
. D
O NOT LEAVE OR STORE
SPECIMENS INSIDE THE CRYOSTAT OVER A LONG PERIOD OF TIME
. D
UE TO A POWER FAILURE
OR OTHER UNEXPECTED MALFUNCTIONS OF THE INSTRUMENT
,
THE SPECIMEN MIGHT BE
DAMAGED
.
Notes
Set the time of the daily defrosting on the control panel. The period of the defrosting takes approximately 1 hour and varies
according to the thickness of the frost.
Possible frost built-up on the microtome or on the knife carrier are not removed by defrosting the instrument. However, the
frost recedes after defrosting as now the evaporator is fully efficient again.
In addition, the instrument is equipped with an immediate defrosting function. The immediate defrosting takes
approximately 90 minutes.
Immediate Defrosting
To start the defrosting immediately:

Press the "Menu" button on the Main screen.

The Menu screen will be displayed.

Press the "Settings" button.

The Menu: Settings screen will appear.