Servicing
Diaphragm Vacuum Pump N 828 / N 838
40
Translation of original Operating and Installation Instructions, english, KNF 121249-121517 09/19
8.3. Replacing the diaphragm and valve plates
8.3.1. AN_-versions (with pump head made of aluminum)
▪
Pump disconnected from mains and de-energized.
▪
Pump is clean and free of hazardous materials.
▪
Hoses removed from pump’s pneumatic inlet and outlet.
Spare part/tool
Quantity
1 Service Set*
1
Phillips screwdriver no. 2
1
Phillips screwdriver no. 1 (only for DC
pumps N 828)
1
Felt-tip pen
1
Tab. 19
*according to Chapter 10
Diaphragm and valve plates/sealings are the only parts of the
pump subject to wear. They are simple to change.
Always change valve plates/sealings and diaphragm at the same
time. If the diaphragm and the valve plates/sealings are not
changed at the same time the nominal performance of the pump is
not guaranteed after the servicing.
WARNING
Dangerous substances in the pump can
cause a health hazard.
Depending on the substance transferred, caustic
burns or poisoning are possible.
➔
Wear protective clothing if necessary, e.g. pro-
tective gloves.
➔
Flush the pump before replacing the diaphragm
and valve plates/sealings (see Chapter 8.2.1).
CAUTION
Danger of burns from hot pump parts
The pump head or motor may be hot even after the
pump has been shut off.
➔
Allow the pump to cool off after operation.
Change the diaphragms and valve plates/sealings in the following
sequence:
a.) Preparatory steps
b.) Remove pump head
c.) Change diaphragm
d.) Change valve plates/sealings
e.) Refit pump head
f.) Final steps.
Requirements
Spare parts/tools
Information on procedure