TEST PROCEDURES
TESTING OF #1 CHECK VALVE
Step 1: Close #1 and #2 shut off valves.
Step 2: Open test cocks No. 2, 3, and 4. Verify that
No. 1 shut off valve is holding tight by observing that
the discharge of water from test cock No. 2 stops.
Step 3: Attach test kit “Vent” hose to No. 1 test cock;
“Low” hose to No. 2 test cock and “High” hose to No. 3
test cock. At this point valves (A) and (C) should be
open and (B) should be closed.
Step 4: Close test cock No. 4.
Step 5: Open test cock No.1. The needle of the
differential gauge will indicate a pressure in excess of
15 psi.
Step 6: Slowly open needle valve (B) until the differen-
tial gauge reads 10 psi. Then close (B). The gauge
reading will not change if No. 1 check is holding tight.
If No. 1 check is leaking, the gauge will drop to 0.
Requirements: The check valve shall be tight against
reverse flow under all pressure differentials.
TESTING OF #2 CHECK VALVE
Step 1: Close test cock No. 1.
Step 2: Open test cock No. 4.
Step 3: Change “Low” hose from test cock No. 2 to
test cock No. 3. Change “High” hose from test cock
No. 3 to test cock No. 4. On the test kit, valves (A) and
(C) should be open and valve (B) should be closed.
Step 4: Open test cock No. 1. The pressure differential
gauge will indicate a pressure in excess of 15 psi.
Step 5: Slowly open needle valve (B) until the gauge
reads 10 psi, then close. If the gauge reading does not
change, No. 2 check valve is holding tight. If No. 2
check is leaking, the gauge will drop to 0.
Note in the above testing: Minor leakage in shut off
valve No. 2 will not affect the test results. However, in
the testing the No. 1 check, leaking shut off valve No. 1
would cause a good first check to fail the test.
Test Procedure for Double Check Valve Assemblies
using Ames Test Kit
The following Test Procedure is one of several that is recog-
nized throughout the United States for verification of the
functioning of Backflow preventers and is not a specific
recommendation. The Ames test kit is capable of performing
any of the recognized Backflow test procedures.
TROUBLE SHOOTING GUIDE
Symptom
Cause
Solution
1. Check valve fails to hold
a. Debris on check disc
Disassemble and clean
backpressure.
sealing surface
b. Leaking gate valve
Disassemble and clean or repair
c. Damaged seat disc or
Disassemble and replace
seat o-ring
d. Damaged guide holding
Disassemble clean or replace
check open
e. Weak or broken spring
Disassemble and replace spring
2. Chatter during flow
a. Worn, damaged or
Disassemble and repair or
conditions
defective guide
replace guide
3. Low flows passing
a. Mainline check fouled
Disassemble and clean
through mainline
valve (3000 CIV only)
b. Meter strainer plugged
Disassemble and clean
c. Damaged mainline seat
Disassemble and replace
disc or seat
d. Broken mainline spring
Disassemble and replace
RP/IS-2000/3000CIV 0035
EDP# 1915232
Printed in U.S.A.
A
B
C
Vent
High
Low
© Watts Regulator Co., 2000
