Testing Procedures For Various Assemblies

This section provides a description of the field test procedures for the 3 most common types of assemblies along with the number of test required to ensure that the assembly is functioning within the standards established by the Safe Drinking Water Act (EPA).  The testing criteria below was provided by Conbraco Mfg.

 Field Test Procedures for Double Check Valve Assembly.

 TEST 1: Purpose- to check valve No#1 for tightness against reverse flow.

 Steps:

1. Bleed water through all four-test cocks to eliminate foreign material.
2. Install appropriate fittings
3. Connect the high side hose to test cock #2 and connect the low side hose to test cock#3.  Connections must be drip tight.
4. Open test cocks #2 and #3, then bleed hoses, making sure to bleed the low side last.
5. Close #2 shutoff valve; then close#1 shutoff valve.
6. By means of the highside needle valve lower the pressure at test cock #2 about 2 psi below the pressure at test cock#3.  If this small difference can be maintained then check valve #1 is reported as tight or okay. Proceed with test #2.
7. Open shutoff valve #1 to pressurize device.
8. Loosely attach the bypass hose to test cock #1, and bleed from the gage through the hose by opening the low side needle valve to eliminate trapped air.  Close low side needle valve.  Tighten bypass hose.  Open test cock#1.
9. Close #1 shutoff valve.
10. By loosening the low side hose at test cock #3, lower the pressure in the device about 10 psi below normal line conditions.
11. Simultaneously open both needle valves very slowly.  If the check valve is holding tight, the high-pressure gage will begin to drip while the low-pressure gage will increase.  Close needle valves.  If the gage shows that a small (no more than 5 psi) backpressure is created and held, then the check valve is reported as “tight.”
12. Close all test cocks remove all equpment and reopen #1 shutoff valve.
13.  

 Test 2: Purpose – to test No #2 check valve for tightness against reverse flow.  Note: a requirement is for the check valve shall be tight against reverse flow under all differentials.

Field Test Procedures for Pressure Vacuum Breaker

Test #1-

Test #2

 Field Test Procedures for Reduced Pressure Zone

Test #1-

Test #2-

Test #3-