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6 Maintenance
BÜCHI
Vac
V-500/V-501/V-502/V-503
6
Maintenance
6.1
Cleaning
Valve head
If the end vacuum of the pump can not be reached the
problem is often caused by stuck valve plates. To clean them
do the following steps:
1) remove all of the connections to the pump and the sound
absorber
2) switch the pump on
3) inject a small amount of about max. 10 ml at one time of
acetone at the inlet side of the pump and wait till the pump
makes the same sound as before injecting the solvent.
The injection should only be done with safety washing bottles
as seen on the picture.
4) Repeat point 3) four to five times
5) Leave the pump running for about 2 minutes and check
then if the end vacuum can be reached.
6) If the end vacuum can not be reached after this cleaning
procedure, repeat it again before going on with Chapter
6.2.
Housing
Before cleaning, please disconnect the apparatus from the
power source.
The housing is made of plastic. Drops of acid must be wiped
away immediately with a damp cloth. Using organic solutions
for cleaning (exception: ethanol) can cause damage and is
not allowed.
Glass parts can be rinsed out with standard cleaning agents
(e.g., mild soap solutions). After they have been cleaned and
dried thoroughly, they must be examined visually for splintered
places or cracks. As the valve unit is in a vacuum during op-
eration, this examination must be carried out conscientiously.
Hoses and gaskets must also be examined visually; if cracks
have developed or if they have become brittle, they must be
replaced with suitable new hoses.
Büchi offers sets of spare parts which make it easier for the
user to obtain spare parts.
The necessary articles can be found in Chapter 8.1, Spare
Parts.
Fig. 24: Cleaning Valve head
