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3
Test Procedures
Double Check Valve Assemblies
Test Check Valve No.1
Step 1: Ensure shutoff #1 is open, shutoff #2 is closed.
Step 2: Connect high side hose to test cock #3, low side to test
cock #2 and open both test cock #2 and test cock #3.
Step 3: Open valve C, then open A to bleed air from the high
side. close valve a, then open B to bleed low side.
Close valve B.
Step 4: Connect vent hose loosely to test cock#1. Open valve
A to vent air from vent hose, Tighten vent hose at test
cock #1, open test cock #1.
Step 5: Close shutoff #1. Slowly loosen hose at test cock #2
until differential gauge rises to 2psi and retighten hose.
If the differential reading does not decrease, record
check valves as “tight”.
Test Check Valve No. 2
Step 1: Move the high side hose to test cock #4, low side to
test cock #3 and open both test cock #3 and test
cock #4. Remove vent hose from test cock #1, open
shutoff #1.
Step 2: Open valve C, then open valve A to bleed air from the
high side. Close valve A, then open valve B to bleed
low side. Close valve B.
Step 3: Connect vent hose loosely to test cock #1. Open valve
A to vent air from the vent hose, Tighten vent hose at
test cock #1, open test cock #1.
Step 4: Close shutoff #1, then slowly loosen hose at test cock
#3 until differential gauge rises to 2psi and retighten
hose. If the differential reading does not decrease,
record check as tight. Remove all hoses and restore
valve to original working condition.
Note:
The assembly will fail both the first and second check
valve tests above, if shutoff #2 leaks excessively. To test for a
leaky #2 shutoff, use the following procedure.
Test for Leaky No. 2 shutoff
Step 1: Connect the high side to test cock #1, low side to test
cock #4. Open test cock #1 and test cock #4. Close
shutoffs #1 and #2.
Step 2: Close valve C. Open valve A, then open valve B
1
⁄
2
turn, loosen hose at test cock #4 to remove air.
Retighten hose.
Step 3: If the differential gauge rises above 0, there is exces-
sive leakage at shutoff #2 and it must be replaced to
test the assembly.
Ball Type Test Valves
A
C
B
Needle
Valve
High Hose
(Yellow)
Low Hose
White or Red
Vent Hose
(Blue)
Test Cock
Test Cock
Test Cock
Test Cock
No. 1
No. 2
No.3
No.4
Material/Tool Requirements:
• #3 Phillips screwdriver or
5
/
16
" diameter rod, length sufficient to
span diameter of check, see Figures A and B.
•
1
/
2
– 13 x 5" fully threaded hex bolt (Service bolt).
•
3
/
4
" open end or socket wrench.
Instructions:
Prior to servicing any Watts valve, it is mandato-
ry to shut down the water system by
closing both the inlet and outlet
shutoff valves. After shutoff valves
are closed, open test cock #2, #3 & #4 to
relieve pressure within the backflow assembly.
1. After #3 test cock has been opened to relieve
pressure, remove #3 test cock from housing.
When repairing an 8" or 10" (200 – 250mm) device, remove
both Victaulic couplers from body. Slide the downstream
Victaulic coupler gasket to the downstream side of the hous-
ing. The upstream Victaulic coupler gasket stays in place.
2. Remove check/s to be maintenanced.
3. Locate the service hole and thread in the service bolt by hand
until it contacts the linkage. (Figure A)
4. Continue to thread in service bolt with the wrench until the
service hole in the linkage is aligned with the service notches
on the spring arbors. (Figure A)
5. Insert the Phillips screwdriver through the arbors and service
hole of the linkage making sure that the tip of the screwdriver
extends past the ends of the arbors by a minimum of
1
/
4
"
(6mm). (Figure B)
6. Back out the service bolt until load is transferred to the screw-
driver. Continue to back out the service bolt until sufficient clear-
ance is achieved to remove the complete spring mechanism.
7.To disconnect linkage, remove retaining clip and pin (store in a
safe location for reinstallation).
8. To remove spring mechanism, grasp the screwdriver at the
center and pull complete assembly straight out and store in a
safe place.
9. Reinstall in reverse.
WARNING –
While the spring mechanism is removed for check
servicing; never pull the screwdriver out or off the support notch-
es on the arbors. Doing so may cause bodily injuries.
Maintenance Instructions
8" – 10" (200 – 250mm)
Figure A
Figure B
Service Hole