Backflow Prevention and Cross Connection Control questions with accurate answers

Backflow Prevention and Cross Connection Control
questions with accurate answers
During DC Test for either check valve, the Check valve is reading below
1.0 psid. What does this indicate? Ans✓✓✓ 1. Dirty or damaged check
disc
2. Dirty or damaged check seat
3. Damaged spring


During DC Test for either check valve, the Check valve reading above
5.0 psid psid. What does this indicate? Ans✓✓✓ 1. Incorrect CV
spring, possible RP spring.


During PVB Air Inlet Test, Air inlet valve does not open, and reading on
field test kit will not drop. What does this indicate? Ans✓✓✓ 1. Leaky
No. 1 shutoff valve
2. Parallel installation with leaky No. 2 shutoff valve


During PVB Air Inlet Test, Air inlet valve does not open, as field test kit
drops to 0.0 psid. What does this indicate? Ans✓✓✓ 1. Air inlet disc
stuck to seat
2. Broken or missing air inlet spring
3."O|d style" pressure vacuum breaker (non- loaded air inlet valve)
4. It is an SVB (See Book 9.5)

, During PVB Air Inlet Test, Air inlet valve opens below 1.0 psid, and
reading on field test kit will not drop. What does this indicate?
Ans✓✓✓ 1. Dirty or damaged air inlet valve disc
2. Scale buildup on seat
3. Damaged spring


During PVB Check Valve Closing Point Test (Test No. 2), water runs
continuously from test cock No. 2. What does this indicate? Ans✓✓✓
1. Leaky No. 1 shutoff valve


During PVB Check Valve Test, Check valve reading below 1.0 psid.
What does this indicate? Ans✓✓✓ 1. Dirty or damaged check valve
disc
2. Dirty or damaged seat
3. Damaged spring


During RP Test 1 or 3, Check Valve No. 1 check reading too low (less
than 5.0). What does this indicate? Ans✓✓✓ 1. Dirty or damaged disc
2. Dirty or damaged seat
3. Guide members hanging up
4. Damaged spring


During RP Test 1, Relief Valve discharges after No. 2 shutoff valve is
closed. What does this indicate? Ans✓✓✓ 1. Normally indicates faulty
No. 1 check valve
• Dirty or damaged disc