Genevac HT-4X Evaporation System
User Manual
30
04-7415 Issue 1-16 August
2014
Condenser
The condenser is controlled by the
evaporator so requires little intervention
from the user. Using the programmable
features of the evaporator’s software,
condenser defrost cycles can be set up to
occur automatically at end-of-run (or for
AD&D
systems) at key points during the
evaporation process, alternatively
condenser defrost can be initiated manually
from the evaporator’s
Select Run
screen.
Automatic defrost and drain
This section applies to
Auto Defrost and
Drain
systems only.
Select the automatic
End of Run Defrost
and Drain
option from the evaporator
Run
Data
screen.
The condenser behaves differently
depending on whether the run is part of a
linked series:
If a linked run follows, the condenser
performs a short defrost and drain
(sufficient to remove any frozen solvent
from the outlet pipe) then the linked run
commences.
If no other runs are linked, or if the run is
the end of a chain of linked runs, the
system performs a full defrost and
drains the condenser.
Automatic defrost and drain can also be
used to facilitate the drying of mixed boiling
point solvents in a single automated
process. Multiple boiling point mixtures
(such as DCM and DMSO) are almost
impossible to evaporate in one operation,
but using automatic defrost and drain,
methods can be set up to perform multiple
operations without the need for manual
intervention between stages.
Automatic defrost and drain also helps
achieve excellent final dryness when
evaporating HPLC fractions.
It is generally advisable to enable automatic
defrost and drain so the system will always
be ready to go, having defrosted and
drained at the end of the previous use.
However, in order to protect the system and
/ or samples from solvent damage, there are
certain circumstances when auto-defrost
and drain should not be used.
Do not use automatic end of run defrost and
drain:
When evaporating TFA or other strong
acids. Vapour may travel back from the
condenser with long term exposure
causing degradation to the evaporation
chamber. Intermediate (short) defrost
and drain is permitted but full defrost
and drain should not be used. Instead,
stop the system, open the door and then
perform a manual defrost and drain. For
this application, Genevac strongly
recommend the use a fume cupboard or
fume extraction system.
At the end of a lyophilisation method.
Water vapour may travel back from the
condenser to the chamber and cause
the lyophilised powders to collapse.
Remove the samples first, then perform
a manual defrost and drain.
Caution:
Do not use automatic
end of run defrost and drain
when evaporating TFA or at the
end of lyophilisation methods.