Heidolph ROTAVAC vario control - Manual (Page 26)

Documents are only to be used and distributed completely and unchanged. It is strictly the users´ responsibility to check carefully
the validity of this document with respect to his product. Manual-no.: 999223 / 08/07/2009
page 26 of 34
➨ Lift diaphragm at the side and position carefully together
with diaphragm clamping disc and diaphragm support disc
in the diaphragm key.
☞ Avoid damaging the diaphragm: Do not bend diaphragm
too much.
➨ Check for washers. Do not mix the washers from the dif-
ferent heads. Assemble the original number of washers
between support disc and connecting rod at the individual
pump head.
☞ Smaller number of washers: The pump will not attain final
vacuum. More washers: Clamping disc will hit head cover;
noise or even blockage of the pump.
☞ Make sure that the square head screw of the diaphragm
clamping disc is correctly seated in the guide hole of the
diaphragm support disc.
☞ Position washers between diaphragm support disc and
rod.
➨ Assemble diaphragm clamping disc, diaphragm and dia-
phragm support disc to connecting rod.
➨ Position new diaphragm between diaphragm clamping
disc with square head screw and diaphragm support disc.
☞ Attention: Position diaphragm with pale side towards dia-
phragm clamping disc (to pump chamber).
7.3 Replacing the valves and assembly of the pump heads
➨ Lift diaphragm carefully.
➨ Apply pressure to the adjacent clamping disc to bring con-
necting rod into upper turning point position if necessary.
☞ Never use a spiky or sharp-edged tool to lift the dia-
phragm.
➨ Use the diaphragm key to grip the diaphragm support disc
below the diaphragm.
➨ Apply pressure to the diaphragm clamping disc to bring
the diaphragm into the lower turning point position. Press
diaphragm key against diaphragm clamping disc, unscrew
and remove diaphragm support disc with diaphragm.
☞ If the old diaphragm is difficult to separate from the support
disc, immerse assembly in naphtha or petroleum ether. Do
not inhale!
☞ Check for washers under clamping disc. Do not mix the
washers from the different heads. Make sure that the origi-
nal number is reassembled at the individual pump head.
7.2 Replacing the diaphragm