Cla-Val CRD40 - Manual

Symptom
Fails to close
when outlet
pressure rises
Fails to open
when outlet
pressure lowers
Probable Cause
Foreign matter on
seating face of seal
O-ring
Cartridge assembly
damaged
Cut or worn stem
O-ring or worn
O-ring groove
Spring compressed
solid
Cartridge assembly
damaged
No spring
compression
Damaged spring
Remedy
Disassemble and
remove
Disassemble and
replace
Replace cartridge
assembly
Loosen
adjustment bolt
Disassemble
and replace
Tighten adjustment
bolt
Disassemble and
replace
Pressure Reducing Control
CRD40
MODEL
Description
The CRD40 Pressure Reducing Control automatically reduces a
higher inlet pressure to a lower outlet pressure. It is a direct act-
ing, spring loaded, diaphragm type control that operates hydrauli-
cally. It is used as a pilot control with Cla-Val automatic control
valves to hold a constant downstream pressure. Cla-Val Model
CRD40 maximum inlet pressure rating: 400 psi
Installation and Adjustment
Before installing the CRD40 Pressure Reducing Control, flush out
line to remove loose dirt and scale which might damage seal ring
and seat. Install control in-line with arrow on valve body pointing
in direction of flow. The CRD40 may be installed in any position.
The standard adjustment range is 15 to 150 psi with a factory set-
ting of 50 psi. To readjust outlet pressure, loosen lock nut and
turn adjustment bolt clockwise (into bell housing) to raise outlet
pressure. To lower outlet pressure setting turn adjustment bolt
counterclockwise (out of bell housing).
Caution: A pressure gauge must be used downstream to verify
correct pressure setting. Do not bottom out adjustment bolt on
bell housing.
Notice: To ensure proper performance and maximum service life
for the CRD40, it is suggested that a program of regular inspec-
tion, testing, maintenance and cleaning be utilized. Annual
inspection and maintenance is recommended.
Disassembly
1. Before starting disassembly remove line pressure from control.
2. Measure distance adjustment bolt protrudes from bell housing.
Loosen lock nut on adjustment bolt and turn adjustment bolt out
of bell housing only to remove spring tension. DO NOT REMOVE
ADJUSTMENT BOLT, SPACER OR lock nut FROM BELL
HOUSING.
3. Unscrew bell housing counterclockwise and remove spring,
spring disc and friction ring.
4. Remove cartridge assembly from valve body by gripping
retaining bolt with pliers and pulling outward away from valve
body.
Reassembly
1. If possible, flush any debris out of valve body by allowing some
water flow while CRD40 is apart.
2. Replace old cartridge assembly with new cartridge assembly.
Carefully push new cartridge assembly into body making sure O-
rings seal tight against both cartridge and body. A small amount
of waterproof grease on O-rings may help cartridge assembly slip
into place.
3. Replace friction ring, spring, spring disc and bell housing with
adjustment bolt in place in order shown on drawing. Friction ring
must be installed as shown in diagram to avoid damage.
4. Turn adjustment bolt into bell housing to original measured set-
ting.
5. After remaining components of control valve pilot system and
main valve are serviced, recheck pressure setting of CRD40 with
flow through the valve. To readjust outlet pressure, loosen outer
lock nut and turn adjustment bolt clockwise (into bell housing) to
raise outlet pressure setting, turn adjustment bolt counterclock-
wise (out of bell housing) to lower outlet pressure setting.
INSTALLATION / OPERATION / MAINTENANCE
Troubleshooting
1 ⁄
2
”
&
3 ⁄
4
”
CRD40 Repair Kit Part Number 20348406K