Cla-Val 92-01/692-01 Quick Manual User Manual

Model installation / operation / maintenance

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INTRODUCTION
The Cla-Val 92-01/692-01 is an automatic valve designed to maintain a
constant downstream pressure regardless of fluctuating demand and sus-
tain the upstream pressure to a predetermined minimum. The control sys-
tem consists of a reducing control sensing downstream pressure changes
and a pressure sustaining control that is sensing the main valve inlet. The
pressure reducing control responds to slight downstream variations in
pressure and immediately controls the main valve to maintain the desired
downstream pressure. The pressure sustaining control is normally held
open by the upstream pressure but closes if this pressure drops to the
control set point. This in turn closes the main valve to sustain the desired
upstream pressure.
INSTALLATION
1. Allow sufficient room around the valve assembly to make adjustments
and for disassembly.
2. It is recommended that gate or block valves be installed on both ends
of the 92-01/692-01 valve assembly to facilitate isolating the valve for
maintenance.
NOTE: BEFORE THE VALVE IS INSTALLED, PIPE LINES SHOULD BE
FLUSHED OF ALL CHIPS, SCALE, AND FOREIGN MATTER
.
3. Place valve assembly in pipe line with flow through valve in direction
indicated on inlet plate or by flow arrows. Check all fittings and hardware
for proper makeup and that no apparent damage is evident.
4. Cla-Val Valves operate with maximum efficiency when mounted in hor-
izontal piping with the cover UP; however, other positions are acceptable.
Due to size and weight of cover and internal components of six inch and
larger valves installation with the cover up is advisable. This makes peri-
odic inspection of internal parts readily accessible.
5.

Caution must be taken in the installation of this valve to insure that

galvanic and/or electrolytic action does not take place. The proper
use of dielectric fittings and gaskets are required in all systems using
dissimilar metals.

OPERATION AND START-UP
1. Prior to pressurizing the valve make sure necessary gauges to mea-
sure pressure in the system are installed as required by the system engi-
neer. A Cla-Val X101 Valve Position Indicator may be installed in the cen-
ter cover port to provide a visual indication of the valve stem position dur-
ing start-up adjustments.
CAUTION: During start-up and test a large volume of water may be dis-
charged downstream. Check that the downstream venting is adequate to
prevent damage to personnel and equipment. All adjustments in pressure
should be made slowly. If the main valve closes too fast it may cause
surging in upstream piping.
2. If isolation valves (B) are installed in pilot system open these valves
(see schematic).
3. Remove cap on the CRL Pressure Relief Control (4). Loosen jam nut
and turn adjusting screw counter clockwise. This puts the CRL in an open
position.
4. Cla-Val CV Flow Control (5 & C) provide adjustable regulation of flow
in and out of the main valve chamber which minimizes pulsations that
sometimes occur at very low flow rates. Loosen jam nuts and turn adjust-
ment screws counterclockwise from closed position 3.5 turns for an initial
setting.
5. Open the upstream gate or block valve just slightly to allow the valve
assembly and pilot system to fill with liquid.
6. Carefully loosen tube fittings at highest points and bleed air from sys-
tem. Carefully loosen the plug at top of main valve cover. If X101 indica-
tor is installed, carefully open vent valve at top of Indicator. Bleed air from
cover and tighten plug. Tighten tube fittings.
7. Open the upstream gate or block valve fully.
8. Slowly open the downstream gate or block valve. Flow should occur
and pressure should remain constant.
9. Adjust the CRD Control (3) to desired outlet pressure. To change pres-
sure setting, turn the adjusting screw clockwise to increase pressure,
counterclockwise to decrease pressure: There should be flow through the
valve when adjusting pressure. When the desired setting has been made,
tighten jam nut and replace cover. An increase in pressure at the outlet will
tend to close the CRD Control and main valve. This action causes the
main valve with CV control (5 or C) to modulate (open and close) main-
taining a relatively constant outlet pressure.

10. Adjust the CRL Control (4) to maintain the desired minimum inlet or
upstream pressure. To change pressure setting, turn the adjusting screw
clockwise to increase the inlet pressure, counterclockwise to decrease
pressure. When the desired setting has been made, tighten jam nut and
replace cover. A decrease in inlet pressure below the set pressure of the
CRL closes the control and main valve. The main valve will modulate to
maintain the upstream pressure at the set point of CRL.

11. To check the operation of the pressure reducing and pressure sus-
taining features of the valve assembly, induce pressure changes at the
valve inlet and outlet.
12. Fine-tune the opening and closing speed of the main valve with CV
control (5 or C) while performing steps 9 and 10.
MAINTENANCE
1. Cla-Val Valves and Controls require no lubrication or packing and a
minimum of maintenance. However, a periodic inspection schedule
should be established to determine how the fluid handled is affecting the
efficiency of the valve assembly. Minimum of once per year.
2. Repair and maintenance procedures of the Cla-Val Hytrol Main Valve
and pilot control components are included in a more detailed IOM manu-
al. It can be downloaded from our web site (www.cla-val.com) or obtained
by contacting a Cla-Val Regional Sales Office.
3. When ordering parts always refer to the catalog number and stock
number on the valve nameplate.

92-01/692-01

MODEL

INSTALLATION / OPERATION / MAINTENANCE

Combination Pressure Reducing and

Pressure Sustaining Valve

SYMPTOM

Main valve
fails to open

Main valve
fails to close

PROBABLE CAUSE

No pressure at valve inlet
Main valve diaphragm assembly
inoperative

CRD Pressure Reducing Control
not opening:
1. No spring compression
2. Damaged spring
3. Spring guide not in place
4. Yoke dragging on inlet nozzle

CRL Control not opening:
1. Adjusting screw turned in too

far (setting too high)

2. Fails to open with spring

compression removed

3. Diaphragm damage (leakage

from cover vent hole)

4. Loose upper diaphragm washer

Foreign matter between disc &
seat of main valve, damaged disc,
scale on stem or disc guide,
diaphragm damaged

X44A Strainer & orifice clogged.
CK2 Shutoff Valve (B2) in control
line closed

CRD Pressure Reducing Control
remains open or sluggish:
1. Spring compressed solid
2. Worn or damaged disc
3. Yoke dragging on inlet nozzle
4. CRD diaphragm damaged or

loose diaphragm nut (leakage
from vent hole in cover)

CRL Pressure Relief Control fails

to close due to lack of spring com-

pression

A mechanical obstruction holding
control open

REMEDY

Check inlet pressure
Adjust CRL Disassemble,
clean and polish stem, disc
guide, replace defective or
worn parts

1. Tighten adjusting screw
2. Disassemble and replace
3. Assemble properly
4. Assemble properly

1. Back off adjusting screw

reset

2. Disassemble, remove

scale, obstruction

3. Disassemble, replace

damaged diaphragm

4. Tighten upper diaphragm

Disassemble main valve,
remove foreign matter,
clean or replace damaged
parts

Remove strainer plug and
Clean screen and orifice
Open CK2 Valve

1. Back off adjusting screw
2. Disassemble, remove

and replace disc retainer

assembly

3. Assemble properly
4. Disassemble, tighten

diaphragm nut replace
diaphragm

Turn adjusting screw in

clockwise

Reset control

Disassemble, locate and
remove obstruction

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