7
For additional testing information send for IS-TK-DP/DL, IS-TK-9A and IS-TK-99E
Testing -
Double Check Valve Assemblies
The following Test Procedure is one of several that is recognized throughout the United States for verifica-
tion of the functioning of Backflow preventers.
The following procedure is not a specific recommendation. The Watts series of test kits are capable of per-
forming any of the recognized Backflow test procedures.
A.
Flush all test cocks.
B.
Turn tester on (before connecting hoses). Tester must read all
zeroes. Close VA and VB.
Test No. 1 - Test No. 1 Check Valve
1. Install high side hose between TC #2 and tester connection A.
2. Install low side hose between TC #3 and tester connection B.
3. Open TC #2 then VA, bleed hose, then close VA.
4. Open TC #3 then VB, bleed hose, then close VB.
5. Install a bypass hose between VB and TC #1. Open TC #1
and bleed by loosening hose connection at VB. Tighten hose
connection, fully open VB.
Push - Print Head (wait) then Push - Star Test
6. Close shutoff valve #2 then #1.
7. Slowly open VA and loser high side pressure about -2 PSID
below the low side pressure (differential reading about -2.0
PSID). Close VA. If reading is maintained, record as “tight”.
If reading returns to 0 and the pressure A increases to pres-
sure B, the check is recorded as leaking. If the reading re-
turns to + PSID, No. 2 shutoff valve is leaking excessively,
and must be replaced to test the valve.
8. Close all test cocks, remove hoses from TC #2 and TC #3
and TC #1. reopen shutoff valve #1.
Proceed to Test No.2.
Push - Stop Test.
Test No. 2 - Test No. 2 Check Valve
1. Install high side hose between TC #3 and tester connection A.
2. Install low side hose between TC #4 and tester connection B.
3. Open TC #3 then VA, bleed hose, then close VA.
4. Open TC #4 then VB, bleed hose, then close VB.
5. Install a bypass hose between VB and TC #1. Open TC #1
and bleed by loosening hose connection at VB. Tighten hose
connection, fully open VB.
Push - Start Test
6. Close shutoff valve #1.
7. Slowly open VA and lower high side pressure about -2 PSID
below the low side pressure (differential reading about -2.0
PSID). Close VA. If reading is maintained, record as “tight”.
If reading returns to 0 and the pressure A increases to pres-
sure B, the check is recorded as leaking. If the reading re-
turns to + PSID, No. 2 shutoff valve is leaking excessively,
and must be replaced to test the valve.
Push - Stop Test.
Watts 775
Watts 775
Watts TK-DP
Watts TK-DP
Test 1
Test 2
VA
A B
VB
VA
VB
A B
It is important that this device be tested periodically in compli-
ance with local codes, but at least once per year or more as ser-
vice conditions warrant. If installed on a fire sprinkler system
all mechanical checks, such as alarm checks, single checks
and backflow preventers should be inspected internally every
one to five years in accordance with NFPA 13 A and NFPA 25
