SULLAIR-HIGH-FLUID-FILTER-DP moderate Sullair WS Controller

High Fluid Filter dP — Clogged Filter

The SULLAIR-HIGH-FLUID-FILTER-DP (Sullair WS Controller) diesel fault code means: High Fluid Filter dP — Clogged Filter. This is a moderate severity code.

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Keep driving?
Yes, but fix soon
DIY difficulty
moderate
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Common Symptoms

  • WS display shows High Fluid Filter dP while running

Probable Causes (Ranked by Likelihood)

  • Fluid filter clogged (more than 20 psi / 1.4 bar across the filter) High
  • Low ambient temperature thickening the fluid Moderate
  • Sensor failure Low

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 fluid filter.

  3. In ambients below 40°F (4°C) a sump heater may be required — cold, thick fluid trips this without a clogged filter.

  4. If it persists, check the sensor, wiring and tubing.

  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

What is the trip point?

More than 20 psi (1.4 bar) differential across the fluid filter while running, per the factory table.

Sources

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

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