Owner's manual

WARNING
Clean pilot valve in a well ventitated area.
Avoid inhalation of solvent fames and
prolonged exposure of skin to cleaning
solvent. Follow all iostractions on the
Material Safety Data Sheet (MSDS) of the
solvent being used. Severe injury or death
may result from improper usage.
f. Thoroughly clean pilot valve body (11). valve cap
(9), and stem assembly (1) in commercial Q
cleaning solvent or equivalent. Allow pilot valve
to completely air dry. Do not “se abrasive of any
kind on stem.
g. Thoroughly clean exhaust silencer plug (10) with
commercial dry cleaning solvent or cqaivalent,
making sure its exhaust ports are open.
NOTE
Pilot valve stem and body are a matched
set. If either is damaged or wora to a non-
serviceable condition, entire pilot valve mast
be replaced.
h. Inspect stem assembly (1) and pilot valve body
(11). If any signs of wear or damage are found,
replace pilot valve.
i. Install stem assembly (1) into valve body (11).
j. Install exhaust silencer plug (10) and valve cap
(9) on pilot valve body (11).
k. Install manifold (7) and assembled pilot valve
with pilot valve gasket (12) onto stand assembly
(8). securing with socket head cap screws (6).
I. Carefully hold upper end of pilot valve’s stem
assembly (1). Attach connecting Iii (2) to pilot
valve’s stem assembly (1) by turning connecting
link’s ball socket nut (3) clockwise.
m. Calibrate sh-oke of power positioner (paragraph
4-2).
n. Return power positioner to service.
6-5. AIR FILTER CLEANING AND DRAINING. I”
normal service, supply air falter and signal air
filter/regulator require draining of water and
debris at least every 6 months. The frequency of this
maintenance will depend on supply system air quality.
After installation, drain both fdters by slowly opening
filter and filter/reg&tors petcock valves. Initially
drain monthly, gradually increasing time between
drahdig. Schedule periodic draining when falters are
approximately l/4 fall. Continue draining water and
debris at this interval unless plant supply air
conditions change. If element in air filter is dirty,
refer to Section VII for replacement procedure.
6-6. DIAPHRAGM CLEANING AND INSPECTION.
Disassemble, clean, and inspect diaphragm assembly
approximately every two years or if power positioner
is not reaching set points. Refer to Figure 6-3 and use
the following procedure.
WARNING
Before performing any maintenance or
repair action on power positioner, shut off
supply air, signal air, and any electrical
supply or electronic signals to power
positioner. Isolate power positioner from all
systems connected to the power positioner.
Severe injury or death may result from
large torque power positioner is capable of
producing, or from electrical shock.
a. Remove power positioner from service.
b. Remove hex head cap screw (1, Figure 6-3) and
washers (2) securing diaphragm cover (3) to
receiver body (4).
c. Remove zero balance spring (5) from top of
diaphragm.
d. Using a clean shop towel, thoroughly wipe off
any di or debris on upper side of diaphragm (6).
e. Visually inspect diaphragm. Replace if nicks,
cuts, or hardened robber areas (from excess heat)
are visible. Refer to Section VII for replacement
procedures.
f. Clean diaphragm cover (3) and zero balance
spring (5) with commercial dry cleaning solvent
and allow to air dry.
g. Align edges of diaphragm (6) with stop ring (7)
to make a” air tight seal.
h. Replace zero balance spring (5).