DeZURIK
PMV P36C and P41C Positioners
used with DeZURIK Pneumatic Actuators
D10327
Page 14
August 2012
Maintenance for Positioners
Pilot Valve
To remove the pilot valve for cleaning:
1. Remove the screw (1) and carefully lift out the
complete assembly (2).
2. Gently remove the spool (3) from the block.
3. Clean the parts, using methylate cleaner or
similar.
4. Blow the parts dry with compressed air.
Note:
If the parts show signs of wear, replace
the assembly. Do not mix parts from other
assemblies.
5. Check the O-rings, then secure and install the
pilot valve assembly to the positioner and
secure it with the screw (1).
6. Ensure the leaf spring (4) on the balance arm (5) is properly fitted in the groove on the spool (6).
7. Check again to ensure smooth operation of the assembly.
Diaphragm
On P41C positioners the I/P unit must be removed
to reach the diaphragm. See Figure 12.
1. Loosen screws (1), remove the diaphragm
cover (2).
2. Loosen screw (3), then remove diaphragm
(4) and washers (5).
3. When installing the diaphragm, place one
washer on each side of the diaphragm.
Ensure the raised circle on the washers is
facing the diaphragm.
4. Install the screw (3) and tighten.
5. Check the O-ring on the diaphragm cover
(2), then install and secure the cover with
screws (1).
Figure 11 – Location of Pilot Valve Spool
Figure 12 – Diaphragm Removal and
Installation
