44
ZTKS0243 / Z31993 / 03
Troubleshooting
6.2.3 During Cooling Down
a. see note on page before
Continued on next page
Indicator Possible reason Solution By
Cooling with liquid 
nitrogen continues 
too slowly.
Empty transpor-
tation dewar.
Refill or replace transportation 
dewar.
Bruker Service
Transfer pressure 
too low.
Increase transfer pressure 
slightly (max. pressure 
0.3 bar).
Bruker Service
Transportation 
dewar is leaky; no 
transfer pressure 
can be applied.
Check transportation dewar 
and replace if necessary.
Bruker Service
Precooling with 
liquid nitrogen 
continues too 
quickly.
Transfer pressure 
too high.
Stop cooling. Adjust correct 
transfer pressure.
Bruker Service
Vacuum in RT 
vessel does not 
reach  
5 x 10
-5
 mbar in 
48 hours.
O-rings may be 
leaky.
Check and clean O-rings and 
slots; replace O-rings if 
necessary:
• of the Vacuum Valve
• of the drop-off plate
• of the reduction and 
sealing flanges
• of the bottom plate 
a
Bruker Service
O-rings may be 
frozen due to contact 
with liquid nitrogen.
1. Stop cooling.
2. Warm up O-ring with 
warm air
3. Wait until the vacuum is 
recovered.
4. Prevent liquid nitrogen 
from splashing on  
O-rings.
Bruker Service
Defective pumping 
unit or pumping line.
Check pumping unit and 
pumping line:  
A vacuum less than 10
-6
 mbar 
must be reached with a 
closed sealing plug.  
Replace if necessary.
Bruker Service