Leica Biosystems CM1850 UV - Manual (Page 30)

30 Instructions for use V 1.5 – 10/2012
7.5 Defrosting
Defrosting the cryochamber actually means defrosting the evaporator to
prevent excessive frost buildup. The evaporator is flushed with hot gas dur-
ing defrosting. The cryochamber virtually is frostfree and does not need to
be defrosted.
The condensation water that is produced during defrosting is collected in a
container, which is located at the front of the cryostat cabinet.
To make sure that the condensation water stemming from the de-
frost cycles drains into the waste container and to avoid the risk of
possible contaminations, ensure that the tap of the waste con-
tainer (2, Fig. 22) is open when operating the instrument. Only shut
the tap when draining the waste container!
The quick freeze shelf is cooled during the automatic cryochamber
defrosting. However, the Peltier element is turned off. The maxi-
mum duration of a defrost cycle is 12 minutes. Defrosting is termi-
nated automatically once the cryochamber has reached a tem-
perature of -5 °C.
Cooling turns back on automatically.
7.5.1 Automatic defrosting of the cryochamber
An automatic defrost cycle takes place once in 24 hours.
The time of the automatic defrost cycle is programmed via the control panel
1 (see 6.2.1 and 6.2.2).
7.5.2 Manual defrosting of the cryochamber
In addition to the programmable automatic defrost cycle a manual defrost
cycle can be activated (see also 6.2.6).
To avoid an unintended defrosting, the activation of a manual de-
frost cycle is confirmed by an audible signal.
Cooling turns back on automatically.
7. Daily use of the instrument