Powers 595 Series 11 Self-Operating Temperature Regulators - Type DB & DS Double Seat, Balanced - Manual (Page 6)

Maintenance
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DA: To only replace the valve plug
1. Before disassembly, the bulb must be cooled 30°F (16°C)
below the lowest point on the thermal system range, and flow
through the valve must be stopped.
2. Figure 5. Relieve all pressure on the spring by turning adjust-
ing nut assembly [31] fully right to left (clockwise from top).
3. Figure 6A. 1" to 2" valves: Use 1-3/8" wrench to loosen lock
nut [11]. Then, use 1-3/8" wrench to unscrew bonnet [20] from
valve body [26]. DO NOT ALLOW the regulator top to rotate.
Lift up regulator top.
5. Remove stem retainer [22] and replace poppet assembly [24]
6. 1” to 2” valves: Install a new gasket [21] between
bonnet and valve body.
7. Replace bonnet and stem into valve body.
8. With valve plug firmly seated, screw stem extension [4] to the
dimension shown in Figure 15 and tighten into place with hex
nut [12].
9. Assemble in reverse order.
DA/RA: To fully disassemble
regulator from valve
1. Before disassembly, the bulb must be cooled 30°F (16°C) below
the lowest point on the thermal system range, and flow through
the valve must be stopped.
2. Figure 5. Relieve all pressure on the spring by turning adjusting
nut assembly [31] fully right to left (clockwise from top).
3. Figure 7. Remove housing bolts [6] and nuts [7] and temperature
adjustment setting scale [8] and lift off thermal system [1] (hous-
ing, bellows, capillary, and bulb).
4. Figure 8. Using one 3/8" wrench and one 5/16" wrench,
carefully loosen and remove piston plate assembly [2,3]
from the stem extension [4].
Lift off spring [19].
5. Figure 9. Use 1-3/8" wrench to unscrew lock nut [11]
and lift off the yoke and bridge assembly [9].
Follow steps 1-5, To fully disassemble regulator from valve.
7. remove housing and thermal system
DA: To replace packing
3/8" Nut
Piston Plate
Assembly
Spring
5/16" Nut
8. remove piston plate/spring
6
Body
Stem Head Retainer
Regulator & Yoke
Double Seated
Poppet Assembly
6A. (DA, 1" to 2" ) lift off regulator from valve body