7
Watson McDaniel Company HSP Valve Manual Rev3 2415800
Figure 5: Pilot Assembly
Allow pilot to cool before
disassembly. Condensate trapped
in the system has the potential to
cause burns or serious injury.
PILOT ASSEMBLY
ITEM
DESCRIPTION
MATERIAL
1
Pilot Body
Steel
2
Cover
Steel
3
Diaphragm
Bronze
4
Gasket
Flexicarb / SS
5
Adjusting Spring
Stainless Steel
6
Adjusting Screw
Steel
7
Stem
Stainless Steel
8
Stroke Limiter
Stainless Steel
9
Bushing
Stainless Steel
10
Blowdown Body
Stainless Steel
11
Blowdown Stem
Stainless Steel
12
Disc
Stainless Steel
13
Main Spring
Stainless Steel
14
Gasket
Stainless Steel
15
Screen
Stainless Steel
16
Seat
Stainless Steel
17
Spring Cup
Stainless Steel
18
Pipe Plug, ¼ NPT*
Steel
19
Spring Button
Stainless Steel
20
Upper Spring Button
Stainless Steel
21
Cap Screws
Steel
22
Spacer
Steel
B
Pressure Pilot Service
1.
Turn the pilot adjusting screw counter-
clockwise to remove all compression from the
pilot spring.
2.
Shut off the inlet gate valve and verify the
downstream pressure is zero.
3.
Remove the pilot cover cap screws and cover.
4.
Inspect the metal diaphragm for cracks and
wrinkles. Replace as required.
5.
Clean any debris from inside the pilot assembly
and diaphragm surfaces.
6.
Unscrew the blowdown body assembly from
the pilot.
7.
Inspect the seat and disc for wear or damage.
Replace as required.
8.
Inspect and clean the pilot screen.
9.
Disconnect the tubing lines from the tee on the
pilot and clean the orifice as required.
10.
Reassemble the blowdown valve assembly and
tighten back into the pilot body.
11.
Reseat the diaphragm and reassemble the pilot
cover making sure to tighten the bolts evenly.
CAUTION
Tee with
Orifice
facing up
*Not shown in drawing view