SULLAIR-HIGH-PACKAGE-PRESSURE serious Sullair WS Controller

High Package Pressure / High Pressure A/B

The SULLAIR-HIGH-PACKAGE-PRESSURE (Sullair WS Controller) diesel fault code means: High Package Pressure / High Pressure A/B. This is a serious severity code.

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DIY difficulty
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Common Symptoms

  • WS display shows High Package Pressure, High Pressure A or High Pressure B

Probable Causes (Ranked by Likelihood)

  • Valves or controls not unloading the machine High
  • Faulty pressure sensor 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. Check operation of the unloading valves and controls.

  3. Check the pressure sensor and replace if defective — a lying sensor produces the same message as real overpressure.

  4. Factory limits for this condition: P2 fault by class: 125/150/175/200 psig; low limit 10 psig

  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 limits apply?

System pressure (P2) fault limits are class-dependent per the manual: 125 psig on a 100 psig machine, 150 on a 125, 175 on a 150, 200 on a 175 (VSD classes differ). The low limit is 10 psig.

Sources

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

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