Learning the Basics
One Hose Test Procedure for
RP 5 Value Test Gauge
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Flush Test Cocks (TC)
Step #1 - Install gauge adapters (if applicable)
Step #2 - Open TC #4 and flush then let trickle
Step #3 - Open TC #3 and flush and close
Step #4 - Open TC #2 and flush and close
Step #5 - Open TC #1 and flush and close
Step #6 - Now Close TC #4
Attach Test Kit
Step #1 - Close gauge manifold control valve and low-pressure bleed
Step #2 - Open gauge high bleed valve
Step #3 - Open TC #2 with trickle flow and attach gauge high-pressure hose
Bleed out all the air or you may get a false reading
Step #4 - Close gauge high-bleed valve and open TC #2 slowly and fully
Test #1 – Check Valve #1 Differential
Step #1 - Close shut off #2 then close shut off #1
Step #2 - Slowly and fully open TC #3
Step #3 - When water stops flowing from TC #3 record the gauge for check valve #1
-- Test Results --
Record the pressure differential across #1 check valve.
If the differential reading is 5 pisd or above,
record #1` check Value is tight.
Test #2 – Relief Valve Opening
Step #1 - Slowly open gauge high-pressure bleed valve
Put your hand under the relief value then Step #2
Step #2 - Feel for relief valve discharge and record gauge valve at opening (First Drip)
Step #3 - Continue to open high-bleed valve and verify that relief valve fully opens
Step #4 - Close TC #2 and TC #3 and remove high-pressure hose
--- Test Results –
The relief valve must drip when the differential gauge is 2 psid or greater
Test #3 – Check Valve #2 Differential
Step #1 - Reestablish pressure to assembly open Shut off #1.
Step #2 - Open TC # 3 with trickle flow and attach gauge High-pressure hose
Bleed out all the air or you may get a false reading
Step #3 - Close gauge high bleed valve and open TC #3 fully
Step #4 - Close shut off #1 or close TC #2 to isolate the supply flow
Step #5 - Slowly and fully open TC #4
Step #6 - When water stops flowing from TC #4, record the gauge
Step #7 - Close TC #3 and TC #4.
Step #8 - Reestablish assembly to pre-test condition.
Step #9 - Remove high-pressure hose
-- Test Results --
Record the pressure differential across #2 check valve.
If the differential reading is 1.0 pisd or above, record #2 check valve as tight.
Field Testing Requirements
RP - One Hose Test Procedure
Wilkins Assemblies
Reduced Pressure Assemblies
The Wilkins 375 is a reduced pressure assembly ( RPA ). It is available in 3/4” – 2” sizes and has been in production since 2004. The body is made of reinforced nylon with a bronze carriage. A lead free version was introduced in 2010 (375XL).
Watts Assemblies
The Watts 919 is a reduced pressure assembly ( RPA ). It is available in ¼” – 2” sizes and has been in production since 2003. The body is made of bronze. The ½” – ¾” 919R10 utilizes 1” 919 repair parts. A lead free version was introduced in 2009 (LF919).
How does the Backflow preventer works
The Watts 994RPDA is a reduced pressure detector assembly ( RPDA ). It is available in 2 ½” – 10” sizes and has been in production since 1999. The body is made of stainless steel. The currently utilizes the ¾” 009M3 for the bypass assembly.
Watts PRDA.