Backflow Prevention and Cross Connection Control Exam All Possible Questions and Answers with complete solution

Relief valve discharges continuously. Problem May be caused by what 5 faults? - Answer-1. Faulty No. 1 check valve (F1CV) 2. Faulty No. 2 check valve with backpressure (F2CVwB) 3. Faulty relief valve (FRV) 4. Relief valve plugged sensing |ine(s) (RVPSL) 5. Relief Valve leaking diaphragm (RVLD) Relief valve discharges intermittently. Problem May be caused by what 4 faults? - Answer-1. Properly working assembly with large pressure fluctuations 2. No.1 check valve reading is close to RV opening point, with small line pressure fluctuation. 3. Water hammer 4. No. 1 check valve leak with intermittent flow through assembly. During RP Test 1, Relief Valve discharges after No. 2 shutoff valve is closed. What does this indicate? - Answer-1. Normally indicates faulty No. 1 check valve • Dirty or damaged disc • Dirty or damaged seat: or, 2. Leak through relief valve diaphragm During RP Test 1, Relief valve would not open; differential on the field test kit would not drop. What does this indicate? - Answer-1. Leaky No. 2 shutoff valve with flow through the assembly (L2SVwF) During RP Test 1, Relief valve would not open, differential drops to zero. What does this indicate? - Answer-1. Relief valve stuck closed due to corrosion or scale (RVSC). 2. Relief valve sensing line(s) plugged.During RP Test 1, Relief valve opens too high (with sufficiently high No. 1 check reading). What does this indicate? - Answer-1. Faulty relief valve • Dirty or damaged disc • Dirty or damaged seat During RP Test 1 or 3, Check Valve No. 1 check reading too low (less than 5.0). What does this indicate? - Answer-1. Dirty or damaged disc 2. Dirty or damaged seat 3. Guide members hanging up 4. Damaged spring