SULLAIR-SEPARATOR-DP-HIGH serious Sullair WS Controller

Separator dP High — Plugged Separator

The SULLAIR-SEPARATOR-DP-HIGH (Sullair WS Controller) diesel fault code means: Separator dP High — Plugged Separator. This is a serious severity code.

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Keep driving?
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DIY difficulty
moderate
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Common Symptoms

  • WS display shows Separator dP High (fault) or High Separator dP (warning)

Probable Causes (Ranked by Likelihood)

  • Plugged separator element(s) High
  • Pressure sensor failure Moderate

Step-by-Step Diagnostic Procedure

  1. The WS Controller is fitted to Sullair STATIONARY electric shop compressors. Portable towable Sullair units (185-class and similar) use different engine-driven controls and a different fault system — this page does not apply to them.

  2. Replace the separator element — plugging is the factory's primary cause.

  3. Check the sensor wiring before and after: a sensor fault produces the same reading.

  4. Factory limits for this condition: warning threshold: P2-P1 + 10 psid offset

  5. Per the factory manual: after resolving a fault condition, press the STOP pad to clear the FAULTED state. If the problem persists after the recommended checks, consult your Sullair distributor or factory service.

Frequently Asked Questions

When does the warning trip?

Per the parameter table, the separator dP warning is based on P2−P1 with a 10 psid offset allowance for an aftercooler or dryer. Rising dP over time is the separator loading up — replacement is maintenance, not failure.

Sources

This page is built from documented references. Verify against your own service info before repair work.

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