8.2 RP Pass/Fail Criteria and Troubleshooting

8.2 RP Pass/Fail Criteria and Troubleshooting

Quick Answer: An RP passes when relief opens at ≥ 2.0 psid, check #2 holds tight against backpressure (reported tight or leaked, no psid), and check #1 is ≥ 5.0 psid and above the relief opening point. Common fails: continuous drip (often fouled check #1), relief < 2.0, check #1 weak or not above relief, check #2 not tight, zone ≈ supply (#1 leaking), or drip only at static (slow #1 leak). Report the fail; recommend repair by a qualified repairer (ASSE 5130 pathway)—do not exceed tester scope.

Pass criteria table (USC 10th Edition field criteria)

Use this table until it is automatic. Every line is independently gradable on worksheets and written items.

Composite assembly pass: all required components pass on a valid procedure. One failed component → assembly fails for compliance purposes even if the other numbers look excellent.

Numeric examples:

Train the last row carefully: ≥ 5.0 is necessary but not sufficient when relief opens high. “Above relief opening point” is a second gate.

Failure patterns you must recognize

Continuous relief drip

Observation: Relief weeps or drips steadily under normal supply with little or no downstream demand.

Common tester-level association: Fouled or leaking check #1 allowing zone pressure to climb toward inlet pressure, collapsing inlet-to-zone differential until the relief cracks open. Debris on the first check seat, damaged disc, or worn elastomer are typical mechanical stories—but as a tester you report continuous discharge and the failed differential/opening data, not a certified internal autopsy.

Other contributors exist (thermal expansion, series RP interaction, elevated downstream pressure events), yet the exam-favorite first association for ongoing drip with soft check #1 numbers is check #1 problem feeding the zone.

Relief opens below 2.0 psid

Observation: Procedure shows opening at 1.0–1.9 psid (or lower).

Call: Fail relief. The designed buffer is gone. Do not “average” with a strong check #1 to invent a pass. A strong check #1 does not legalize a weak relief set.

Check #1 below 5.0 psid or not above relief

Observation: Static differential 3.5 psid; or 5.2 psid with relief opening at 5.4 psid.

Call: Fail check #1. Write both numbers on the report so the repairer sees whether the problem was absolute margin, buffer above relief, or both.

Check #2 fails tightness against backpressure

Observation: With backpressure applied, the differential collapses to the relief opening point and the relief discharges; pressure equalizes across #2 in reverse.

Call: Fail check #2. Downstream pollution or elevated customer pressure can more readily load the zone if #2 will not seat reverse—exactly why this test exists.

Zone essentially equals supply

Observation: Under static conditions, zone pressure tracks inlet pressure; differential near zero; relief may be wide open or dumping hard.

Tester-level reading: Check #1 leaking (or not seating). The reduced-pressure zone has collapsed. This is an urgent compliance fail, not a paperwork quibble.

Drip only at static / no demand

Observation: During flow, relief is quiet; when the system goes static, a slow drip appears.

Pattern: Often a slow check #1 leak. Flowing conditions can hold a temporary differential that masks a marginal seat; when velocity stops, leak-down raises zone pressure until the relief cracks. Capture static data—do not certify pass based only on a flowing glance at a quiet relief.

Troubleshooting vs tester role

Ethical line: Diagnose at the level of which test failed and what the symptoms were. Do not over-claim internal failure modes you did not open. Do not perform repairs you are not authorized to perform. The written exam rewards knowing that 5110 is tester qualification; repair is a separate competency (often associated with 5130 in the Series 5000 family).

Report language that survives audit

Good report fragments:

• “Relief opening point 1.6 psid — fail (≥ 2.0 required).”
• “Check #1 static 4.7 psid — fail (≥ 5.0 and above relief required).”
• “Check #2 would not hold tight against backpressure — leaked / fail.”
• “Continuous relief discharge observed at static; check #1 differential insufficient — assembly fails; recommend repair by qualified repairer and retest.”

Avoid:

• “Probably fine; drip is normal.” (Continuous drip is not “normal protection working.”)
• “Opened relief spring ½ turn; now passes.” (Unauthorized adjustment narrative.)
• “All checks OK” when one line failed.

Connecting symptoms to next actions

1. Complete the valid test (or stop safely if the assembly is flooding the room—isolate per site rules and document).
2. Mark fail on each failed component.
3. Notify per purveyor/AHJ rules (failed assemblies often cannot remain in unlimited service without a plan).
4. Recommend qualified repair—not DIY spring tweaks by untrained staff.
5. Retest after repair before calling the assembly compliant.

Exam traps

• Treating 2.0 as a check #1 number or 5.0 as a relief number.
• Passing check #1 on ≥ 5.0 alone while ignoring above relief.
• Calling continuous drip “thermal expansion” every time without recording differentials.
• Confusing tester observation with repair authorization.
• Forgetting check #2 is about backpressure tightness (tight/leaked, no psid), not a forward flow boast.

When criteria and patterns are solid, Chapter 8.1’s procedure produces numbers you can defend—and 8.2 turns those numbers into clean pass/fail decisions.