4
Excessive line pressure when STP is switched Off. Note: the
pressure thresholds vary; see Table I, Appendix A, Page 15.
Probable Causes:
1.
Sticking/stuck relay (PLLD only).
2.
Clogged functional element (Red Jacket STP).
3.
Faulty pressure transducer.
4.
Incorrectly adjusted check valve relief, or incorrect valve (FE
Petro STP).
5.
Faulty check valve.
6.
Functional element relief valve has not been disabled (Red
Jacket STP).
7.
Vent closing screw on functional element not fully retracted.
8.
STP is being switched On by another device not detected by
the console - e.g., Healy vapor recovery (PLLD only).
9.
Bad PLLD Interface Module (PLLD only).
10. Cross-wired transducers (PLLD only).
11. Transducer incorrectly wired to wrong side of STP capacitor
(WPLLD only).
Troubleshooting Guidelines:
Switch On the STP for 10 seconds to pressurize the line. Shut
the STP Off, wait 5 seconds and measure the line side pump-off
pressure. It should be less than 27 psi. If it is, the problem is
intermittent, otherwise the problem is continuous. Items 1,5, 8,
and 10 are the most common causes intermittent failures. Items
1, 2, 3, 4, 6, 7, 9, 10, and 11 are the most common causes of
continuous failures.
HIGH PRESSURE WARNING/ALARM (Pre 19)
