Trouble Shooting

Question 1

When testing a DCVA w/ a 3-valve differential gauge, what would cause water to continue to discharge from test cock #4 while testing check valve #2

Answer 1

Shut off #1 and shutoff #2 could both be leaking

Question 2

When testing a DCVA w/ a 3-valve differential gauge, water continuous to discharge from test cock #4 while testing check valve #2. What equipment could be used to troubleshoot the DCVA

Answer 2

Bleed off assembly

Question 3

When testing a PVBA w/ a 3-valve differential gauge, why will the low side control valve have to be opened more than 1/4 turn while testing the air inlet valve?

Answer 3

Shutoff #1 is leaking or not closed properly

Question 4

When testing a PVBA w/ a 3-valve differential gauge, why will test cock #2 continue to discharge water when testing the check valve?

Answer 4

Shutoff #1 is leaking

Question 5

When testing an RP, what can cause the relief valve opening psid to be too low?

Answer 5

the relief valve spring is weak

Question 6

What will most likely cause the RP relied valve to discharge intermittently?

Answer 6

a low buffer w/ line pressure fluctuations

Question 7

When testing an RP, what will most likely be the cause of the relief valve to remain open?

Answer 7

The sensing line is plugged

Question 8

What will most likely cause the RP check valve #1 psid to be too low?

Answer 8

a weak #1 check valve spring

Question 9

What will most likely be the cause of the DCVA check valves to leak?

Answer 9

dirty, worn or damaged seats

Question 10

What causes the PVB air inlet valve to not open during a back siphonage condition?

Answer 10

the air inlet valve is stuck closed

Question 11

When testing an RP, what is the probable cause of a continuously discharging relief valve that begins after closing shutoff #2?

Answer 11

check valve #1 is leaking

Question 12

When testing an RP, what is the cause of the relief valve failing to open, when opening the low side control valve to test the relief valve opening psid?

Answer 12

shutoff #2 is leaking or not closed properly

Question 13

When testing an RP w/ a 3-valve differential gauge, what would cause the psia to drop a little before reaching a steady state when opening the bypass control valve to test check valve #2?

Answer 13

disc compression

Question 14

When testing an RP w/ a 3-valve differential gauge, what would cause a fluctuating psid w/ an occasional spitting of the relief port?

Answer 14

water hammer upstream of the RP

Question 15

When testing a DCVA w/ a 3-valve differential gauge, what causes water to continue to discharge from test cock #3 while testing check valve #1?

Answer 15

failure to close shutoff #1

Question 16

An RP is subject to backflow caused by back pressure, check valve #2 is fouled, what will happen?

Answer 16

The relief valve will open

Question 17

When testing CV #1 of a DCVA using a pressure differential gauge where is the equipment connected to

Answer 17

test valves 2 and 3

Question 18

Both check valves of an RP have been replaced, check valve 1 and 2 have been interchanged, what will happen when the assembly is put back in service

Answer 18

The relief valve will continually discharge

Question 19

What would occur when testing an RP check valve #2 failed to close tight

Answer 19

Differential gauge pressure would fall to the relief valve opening point