Cla-Val CDS6-A - Manual

INTRODUCTION
The Cla-Val Model CDS6 Altitude Control is a spring loaded, 3-way,
diaphragm-actuated control that provides high-level shut-off for Cla-Val
Altitude Control Valves. It remotely senses pressure in the reservoir or
tank. There are five altitude ranges available, 5 to 40 feet, 30 to 80 feet,
70 to 120 feet, 110 to 160 feet and 150 to 200 feet. The spring adjusting
nut can be set to stop flow into the reservoir within these ranges.
INSTALLATION
The CDS6 Altitude Pilot Control is normally supplied mounted on a
Cla-Val 210 Series Altitude Valve which should be installed in a horizon-
tal run of pipe with the main valve cover up. Two line block valves are
recommended for valve servicing. If the CDS6 is mounted from the main
valve by a few feet, then it must be installed with adjustment springs up
for ease of adjustment and servicing. Consult factory for recommenda-
tions.
After the Cla-Val 210 Series Altitude Valve is installed in the pipeline
close to the reservoir, install the required remote sensing line from the
CDS6 to the reservoir or tank. The sensing line allows the CDS6 to
sense the static pressure head of the reservoir. The sensing line should
not be installed in the flowing line between the valve and the reservoir or
into turbulent flow area. These locations do not reflect the true static
head of the reservoir.
The remote sensing line should be 3/4" or larger copper tubing or
Schedule 40 PVC pipe. Galvanized pipe is not recommended. The sens-
ing line should slope (minimum 2 degrees) upward from the CDS6
toward the reservoir to self -purge air out of the line. The sensing line
should have no high points to entrap air. A shutoff valve at the reservoir
connection is recommended. For above ground reservoirs, the connect-
ing point for the sensing line should be a minimum of 12" to 18" above
reservoir bottom (if filling from bottom) or at fill pipe connection (if filling
from side). Minimum high-level set-point adjustment is approximately
five feet above the remote sensing point of connection.
Note: Please make sure to remove the plastic plug from the drain port
before putting the valve in service if pilot drains to atmosphere.
OPERATION, START-UP AND ADJUSTMENT
When the reservoir pressure (head) is lower than the setpoint of the
spring on the CDS6 Altitude Control ports "1" and "D" are interconnect-
ed. This relieves the main valve cover pressure to atmosphere. Line
pressure then opens the main valve to start filling the reservoir.
Reservoir sensing pressure increases as the liquid level rises in the
reservoir. When the sensing pressure increases to the set point of the
CDS6 control spring, the control shifts interconnecting port "S" and port "1".
This pressurizes the main valve cover chamber and the main valve closes.
By turning the adjusting nut the liquid level shutoff point will be changed.
Turn the adjusting nut clockwise to raise the liquid level shutoff point;
counterclockwise to lower the liquid level shutoff point. Follow the gen-
eral operation and start-up instructions regarding purging air from the
valve control system.
MAINTENANCE AND INSPECTION
Under normal operating conditions the CDS6 Altitude Control will be
trouble free. There is a visual check possible to determine if there is
damage to the diaphragm in the control. The Lower Cover/Pilot (a) is
vented to atmosphere by means of a small hole in the wall of the cast-
ing. If water is discharging out of this opening, the diaphragm should be
inspected for damage.
One other visual check and indication of a problem is continuous dis-
charge from the drain port ("D") at the bottom of the CDS6.
The volume of drained water will vary according to the valve size.
Continuous draining after main valve has fully opened will indicate a
problem. Refer to the service suggestions to check for probable causes
and remedies.
DISASSEMBLY
During preventive maintenance or service to the CDS6 Altitude Control,
all pressure to the control must be shutoff. The CK2 shutoff cocks in the
main valve control lines should be closed before starting disassembly.
Main valves 4" and larger have CK2 cocks installed, however main
valves smaller than 4" normally do not, therefore requiring closure of
shutoff valves in the main line at the valve inlet and outlet. The shutoff
cock or valve in the sensing line to the reservoir must also be closed.
WARNING: Failure to shutoff and release pressure prior to any
disassembly can result in serious damage to equipment or
injury to personnel.
1. Disconnect tubing at the CDS6 Altitude Control.
2. Remove two mounting caps screws and two lock washers.
3. Remove CDS6 Altitude Control from main valve to work bench or
clean area. Parts must be kept clean.
DISASSEMBLY OF UPPER SPRING SECTION
1. Unscrew adjusting nut (4) from upper stem (5).
NOTE: Count the number of turns required to remove the nut (4),
record this information for reference when reassembling.
The CDS6 Altitude Control can then be approximately reset for the
same reservoir liquid level shut-off point.
2. Remove the thrust washer (3), swivel retainer (2) and spring
retainers if applicable.
3. Remove Spring(s) (6), bellows (7) and set-screw (8)
4. Remove twelve hex nuts (33), and twelve bolts (32), and set
mounting bracket (29) aside.
Note: Assembly contains two (of twelve) longer bolts
which are used for the mounting bracket.
ALTITUDE CONTROL
CDS6
29330-06F
29330-07H
29330-08K
29330-09B
29330-10D
CDS6 STOCK
NUMBER
2" SIZE
CDS6 STOCK
NUMBER
2 1/2" SIZE &
LARGER
29330-01E
29330-02G
29330-03J
29330-04A
29330-05D
ALTITUDE
RANGE
(FT H
2
0)
5 - 40
30 - 80
70 - 120
110 - 160
150 - 200
NUMBER
OF
SPRINGS
1
2
3
4
5 0.32
0.64
0.96
1.28
1.60 0.75
1.50
2.20
3.00
3.70
ALTITUDE
CHANGE
PER TURN
PSI
CHANGE
PER TURN
MODEL
INSTALLATION / OPERATION / MAINTENANCE