Siemens Maxum II PD PA AP Service Manual page 51

Valve Reassembly
Use the Valve Assembly Fixture, Siemens PN 2020281-001, properly align the Diaphragms
when rebuilding the Model 50 Valve. The fixture consists of a base (1), 2 guide pins (2) and a
diaphragm placement disc (3). This fixture will allow the user to place the diaphragm in the
center of the valve. If the diaphragm is not in the center it may leak.
Model 50 Index Marks
Figure 4-12
1. Remove the old diaphragms from the plates. DO NOT attempt to reuse the old diaphragms.
2. With the pins installed in the fixture base, place the bottom plate of the valve on the base.
The pins should fit in the mounting holes on the bottom plate and hold it in place.
3. Position the placement disc on the bottom plate and set the diaphragm in place.
4. Carefully remove the placement disc without moving the diaphragm. Inspect the diaphragm
for proper alignment. If the diaphragm is not in the center of the plate, repeat the placement
procedure using the placement disc.
5. Place the middle plate on the valve taking care to use the correct holes. Check the
alignment mark on the side of the plate. It should align with the mark on the bottom plate.
If not, the middle plate is upside down and must be removed, turned over, and reinstalled
correctly.
6. Remove the old diaphragms from the plates. DO NOT attempt to reuse the old diaphragms.
7. With the pins installed in the fixture base, place the bottom plate of the valve on the base.
The pins should fit in the mounting holes on the bottom plate and hold it in place.
8. Position the placement disc on the bottom plate and set the diaphragm in place.
Maxum II Valves and Oven Components
Service Manual, 10/2018, A5E42019844001
Model 50 Valve Assembly Details
4.3 Model 50 Valve
Valve Assembly Fixture 2020281-001
Valves
51