BAT Troubleshooting & Diagnostics 3 — Questions and Answers
Question 1: A spill-resistant pressure vacuum breaker (SRPVB) is being tested and the check valve holds 1.0 psi but the air inlet valve opens at 3.0 psi differential. What is the test result?
- Pass — the air inlet valve opened before check valve failed
- Fail — the air inlet valve must open at no more than 1.0 psi differential (Correct answer)
- Pass — 3.0 psi is within acceptable range for SRPVBs
- Inconclusive — the test must be repeated
Correct answer: Fail — the air inlet valve must open at no more than 1.0 psi differential
The air inlet valve of a SRPVB must open at no more than 1.0 psi differential; opening at 3.0 psi indicates failure.
Question 2: After completing an RPBA test, the tester reopens the downstream shutoff and hears the relief valve briefly discharge water. What does this indicate?
- Normal operation as the assembly re-pressurizes (Correct answer)
- The #2 check valve has failed during the test
- The relief valve seat is permanently damaged
- The zone pressure exceeded supply pressure
Correct answer: Normal operation as the assembly re-pressurizes
A brief discharge when the downstream shutoff is reopened is normal as the assembly adjusts to the restored downstream pressure and the relief valve briefly sees zone pressure equalization.
Question 3: A tester is evaluating an RPBA where the relief valve opens at a differential of 1.5 psi below supply pressure. What should be recorded?
- Pass — relief valve opened (Correct answer)
- Fail — relief valve must open at no more than 2.0 psi below supply
- Pass — 1.5 psi is within any acceptable range
- Fail — relief valve must not open during testing
Correct answer: Pass — relief valve opened
The relief valve must open at a differential of 2.0 psi or less below supply pressure; a reading of 1.5 psi meets this criterion and the assembly passes this portion of the test.
Question 4: During a DCVA test, after closing the downstream shutoff and opening TC #4, the gauge needle slowly rises. What condition does this indicate?
- Normal gauge settling behavior
- The #2 check valve is leaking under backpressure (Correct answer)
- The upstream shutoff is not fully seated
- Test cock #3 is partially blocked
Correct answer: The #2 check valve is leaking under backpressure
A slowly rising pressure at TC #4 after isolating the downstream side indicates the #2 check valve is leaking, allowing downstream pressure to equalize with zone pressure.
Question 5: A tester is unable to get a stable reading on an RPBA because the building's boiler keeps cycling. What is the most appropriate response?
- Estimate the readings and mark the test as complete
- Shut down the boiler before completing the test
- Coordinate with the building owner to disable the boiler temporarily during testing (Correct answer)
- Test only during boiler off cycles and record the lowest readings
Correct answer: Coordinate with the building owner to disable the boiler temporarily during testing
Coordinating with the building owner to temporarily disable cycling equipment during testing ensures stable conditions and accurate results without unauthorized intervention.
Question 6: What does it mean if both needle valves on a differential pressure test kit are closed and the high side gauge reads higher than the low side gauge with no assembly connected?
- The test kit is working correctly
- The test kit gauges are not zeroed properly and need calibration (Correct answer)
- The hoses are connected in reverse
- This is impossible and indicates a defective gauge
Correct answer: The test kit gauges are not zeroed properly and need calibration
With no assembly connected and both needle valves closed, both gauges should read the same (atmospheric or supply); unequal readings indicate gauge error requiring calibration.
Question 7: During a PVB test, the tester opens the bypass needle valve and the gauge drops to zero. What is the most likely conclusion?
- The check valve is holding properly
- The air inlet valve has failed open and cannot hold pressure (Correct answer)
- The test cock is blocked
- The supply pressure is too low to test
Correct answer: The air inlet valve has failed open and cannot hold pressure
If pressure drops to zero when the bypass is opened, the air inlet valve is open (failed or normal operation) and is venting pressure — the tester must evaluate whether this occurs at the correct differential.
BAT Troubleshooting & Diagnostics 3
A spill-resistant pressure vacuum breaker (SRPVB) is being tested and the check valve holds 1.0 psi but the air inlet valve opens at 3.0 psi differential.
What is the test result?