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.
- DIY difficulty
- moderate
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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
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.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
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.
Check operation of the unloading valves and controls.
Check the pressure sensor and replace if defective — a lying sensor produces the same message as real overpressure.
Factory limits for this condition: P2 fault by class: 125/150/175/200 psig; low limit 10 psig
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.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- Sullair WS Controller User Interface Manual, P/N 02250165-411 (Table 5-1 Troubleshooting Guide)distributor-hosted copy of the official Sullair manualdistributor-hosted copy of an official Sullair factory manual
Commonly Affected Vehicles
- Sullair STATIONARY electric rotary-screw compressors with the WS Controller (including VSD packages)
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