BACKFLOW TROUBLESHOOTING
CERTIFICATION EVALUATION QUESTIONS
ANSWERS COMPLETE SOLUTION VERIFIED
PASS
●● When testing the air inlet of a pressure vacuum breaker the hose(s)
on the test kit shall be connected in this manner:
Answer: High side hose to the #2 testcock
●● When testing the #1 check valve of a double check valve assembly
you have opened the #3 testcock to the atmosphere. The water recedes
from the sight tube. How do you proceed?
Answer: Lower the test kit to the centerline of the assembly; record the
reading as the static pressure drop across the #1 check valve. Note that
the #2 check valve and the #2 shut off valve are leaking and terminate
the test.
●● As you move water from the high side of the #1 check valve to the
low side of the #2 check valve of a reduced pressure principle backflow
prevention assembly, the indicator on the test kit falls to the low end of
the scale and the differential pressure relief valve discharges a
continuous stream of water. How do you proceed?
Answer: Open the low side bleed needle valve to re-establish differential
pressure above the apparent differential pressure to give the #2 check a
second chance.
,●● When testing a double check valve assembly and the #1 check valve
fails you may proceed in the following manner:
Answer: Fail the #1 check valve and continue to test the #2 check valve
●● The correct procedure to test the #1 check valve of a double check
valve assembly is to:
Answer: Install the bleed arrangement on the #2 testcock before purging
air from the test kit
●● As you start to test the air inlet on a pressure vacuum breaker you
close the #2 shut off valve, raise your test kit to the appropriate elevation
and close the #1 shut off valve. You open the high side bleed needle
valve one quarter turn. Water continues to discharge from the high side
bleed needle valve and the indicator on your test kit remains at the high
side of the scale. How do you proceed?
Answer: Open the #1 testcock to compensate for a leaking #1 shut off
valve.
●● Regarding question #4, after you have opened the low side bleed
needle valve and re-established the differential pressure above the
apparent differential pressure, you close the low side bleed needle valve.
Now you test kit indicates an acceptable value for the actual differential
pressure across the #1 check valve. How do you proceed?
Answer: Accept the value as the actual differential pressure across the #1
check valve
, ●● When testing the #2 check valve of a double check valve assembly
you open the #4 testcock. Water continues to discharge from the sight
tube and the bleed valve arrangement, after you have opened the bleed
valve arrangement completely on the #3 testcock. How do you proceed?
Answer: Close the bleed valve arrangement and open the #2 testcock to
compensate for a leaking #1 shut off valve
●● When testing the #2 check valve of a double check valve assembly
you open the #4 testcock. The water in the sight tube recedes. How do
you proceed?
Answer: Lower the test kit to the centerline of the assembly and record
the reading on the test kit noting the #2 shut off valve is leaking with
demand.
●● When testing the #1 check valve of a double check valve assembly it
is necessary to use the bleed valve arrangement to compensate for a
leaking #1 shut off valve. The static pressure drop across the #1 check
valve as indicated by the test kit is 0.6 psid. How do you proceed
Answer: you cannot continue the test until the #1 check valve has been
repaired.
●● If the appropriate action is taken regarding question #7 and only a
slight amount of water discharges from the valve that is open but then
stops, how do you proceed?
CERTIFICATION EVALUATION QUESTIONS
ANSWERS COMPLETE SOLUTION VERIFIED
PASS
●● When testing the air inlet of a pressure vacuum breaker the hose(s)
on the test kit shall be connected in this manner:
Answer: High side hose to the #2 testcock
●● When testing the #1 check valve of a double check valve assembly
you have opened the #3 testcock to the atmosphere. The water recedes
from the sight tube. How do you proceed?
Answer: Lower the test kit to the centerline of the assembly; record the
reading as the static pressure drop across the #1 check valve. Note that
the #2 check valve and the #2 shut off valve are leaking and terminate
the test.
●● As you move water from the high side of the #1 check valve to the
low side of the #2 check valve of a reduced pressure principle backflow
prevention assembly, the indicator on the test kit falls to the low end of
the scale and the differential pressure relief valve discharges a
continuous stream of water. How do you proceed?
Answer: Open the low side bleed needle valve to re-establish differential
pressure above the apparent differential pressure to give the #2 check a
second chance.
,●● When testing a double check valve assembly and the #1 check valve
fails you may proceed in the following manner:
Answer: Fail the #1 check valve and continue to test the #2 check valve
●● The correct procedure to test the #1 check valve of a double check
valve assembly is to:
Answer: Install the bleed arrangement on the #2 testcock before purging
air from the test kit
●● As you start to test the air inlet on a pressure vacuum breaker you
close the #2 shut off valve, raise your test kit to the appropriate elevation
and close the #1 shut off valve. You open the high side bleed needle
valve one quarter turn. Water continues to discharge from the high side
bleed needle valve and the indicator on your test kit remains at the high
side of the scale. How do you proceed?
Answer: Open the #1 testcock to compensate for a leaking #1 shut off
valve.
●● Regarding question #4, after you have opened the low side bleed
needle valve and re-established the differential pressure above the
apparent differential pressure, you close the low side bleed needle valve.
Now you test kit indicates an acceptable value for the actual differential
pressure across the #1 check valve. How do you proceed?
Answer: Accept the value as the actual differential pressure across the #1
check valve
, ●● When testing the #2 check valve of a double check valve assembly
you open the #4 testcock. Water continues to discharge from the sight
tube and the bleed valve arrangement, after you have opened the bleed
valve arrangement completely on the #3 testcock. How do you proceed?
Answer: Close the bleed valve arrangement and open the #2 testcock to
compensate for a leaking #1 shut off valve
●● When testing the #2 check valve of a double check valve assembly
you open the #4 testcock. The water in the sight tube recedes. How do
you proceed?
Answer: Lower the test kit to the centerline of the assembly and record
the reading on the test kit noting the #2 shut off valve is leaking with
demand.
●● When testing the #1 check valve of a double check valve assembly it
is necessary to use the bleed valve arrangement to compensate for a
leaking #1 shut off valve. The static pressure drop across the #1 check
valve as indicated by the test kit is 0.6 psid. How do you proceed
Answer: you cannot continue the test until the #1 check valve has been
repaired.
●● If the appropriate action is taken regarding question #7 and only a
slight amount of water discharges from the valve that is open but then
stops, how do you proceed?
