Watts LF909 - Manual (Page 4)

4
The following Test Procedure is one of several that is rec og nized
through out the Unit ed States for ver i fi ca tion of the func tion ing of
backflow pre ven ters.
The following procedure is not a specific rec om men da tion. The
Watts se ries of test kits are ca pa ble of per form ing any of the rec og-
nized backflow test procedures.
A. Open TC #4 and flush test cocks Nos. 1, 2, and 3 on BF
assembly, then close TC #4.
B. Turn tester on (before connecting hoses). Tester must read all
zeros. Close VA and VB.
Test No. 1 - Relief 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 VB then TC #3. Now open VA then TC #2 slowly. Close
VA then VB.
4. Close #2 shutoff valve.
5. Observe the apparent first check valve differential pressure (A -
B).
6. Install bypass hose between VA and VB. Open VB and bleed air
by loosening hose connection at VA. Tighten hose connection
and close VB.
Push - Print Head (wait) then Push - Start Test
7. Open VA, then slowly open VB (no more than 1⁄4 turn). When
relief valve drips, push the “hold” button for 2 seconds. Record
reading (must be 2 psid or more).
Push - Stop Test
8. Close VA and VB.
Test No. 2 - Test No. 2 Check Valve
9. Install bypass hose between VA and TC #4. Open VA, then
bleed air by loosening hose connection at TC #4. Tighten hose
connection. Close VA.
Push - Start Test
10. Open VB to reestablish pressure with in the “zone”. Close VB.
11. Open VA then TC #4. If relief valve does not drip, record second
check valve as “closed tight”.
Test No. 3 - Test No. 1 Check Valve
12. Open VB to reestablish first check valve differential pressure.
Close VB. Record pressure dif fer en tial.
Stop Test (Push Stop Test twice)
13. Close test cocks and remove tester, return assembly to normal
operating condition.
For complete testing information, send for IS-TK-9A or IS-TK-DP/DL.
Watts TK-DP
RPZ
Test 1
RPZ
Test 2
RPZ
Test 3
VA A B VB
VA B VB A
VA B VB A
Test Procedure for
Reduced Pressure Zone
Backflow Preventers
For repair kits and parts, refer to Backflow
Prevention Products Repair Kits & Service Parts
price list PL-RP-BPD on www.watts.com