Why Your Ingersoll Rand SSR Rotary Compressor Might Not Build Pressure
If your Ingersoll Rand SSR rotary screw compressor is running but not building pressure, it can quickly derail production. Before you start tearing things apart, let’s break down the most common reasons this happens - and what you can check to get back up and running.
This guide applies to many Ingersoll Rand SSR models, including popular units like the SSR-EPE50.
1. Intake Valve Issues
The intake valve controls how much air enters the compressor element. If it’s stuck open or not actuating properly, your compressor may run without pulling in enough air to build pressure.
What to check:
- Inspect for mechanical binding or dirt buildup in the valve assembly.
- Check control air lines for leaks or blockages.
- Verify actuator solenoids are functioning properly.
2. Air/Oil Separator Problems
A clogged or saturated air/oil separator can restrict flow and prevent the system from pressurizing correctly. While separators are designed to remove oil mist from compressed air, they can become a major bottleneck when overdue for replacement.
What to check:
- Check differential pressure across the separator element.
- Look for excessive oil carryover or high oil consumption.
- Inspect for signs of collapse or internal damage.
3. Leaks in the System
Even small leaks in piping, fittings, or downstream equipment can keep your SSR from reaching its set pressure. This is one of the most overlooked causes.
What to check:
- Listen for hissing sounds around connections and hoses.
- Spray soapy water on suspect joints to spot bubbles.
- Inspect drain valves and flange gaskets for damage.
4. Problems with the Pressure Control System
If your SSR’s pressure sensor, transducer, or control setpoints are malfunctioning, it might shut off prematurely or fail to load properly, keeping system pressure too low.
What to check:
- Confirm the set pressure matches operational needs.
- Inspect wiring and sensor connections for corrosion or loose terminals.
- Check controller error codes for additional clues.
5. Check Valves Stuck or Failing
Check valves prevent backflow and help maintain system pressure. If stuck open or leaking, they can cause the compressor to run continuously without achieving target pressure.
What to check:
- Remove and inspect the main discharge check valve for wear or debris.
- Replace if there’s visible damage or poor sealing surfaces.
What Does Low Sump Pressure Mean on an Ingersoll Rand SSR?
If your Ingersoll Rand SSR is showing low sump pressure or is struggling to build normal operating pressure, treat the low pressure as a symptom rather than assuming one specific component has failed.
Start by checking the same areas that affect how the compressor loads, moves air, and maintains pressure:
- Intake valve operation – Make sure the valve is opening and responding correctly when the compressor loads.
- Control air lines and solenoids – Leaks, restrictions, or control problems can interfere with proper loading.
- Air/oil separator condition – Check separator differential pressure and service history.
- Pressure sensors and controls – Confirm the pressure signal and controller settings are accurate.
- Leaks or failing valves – Air escaping through piping, fittings, drains, or valves can prevent normal pressure from developing.
The exact troubleshooting process can vary by SSR model and controller, so record any fault messages or pressure readings and refer to the service information for your specific machine before replacing components.
Stay Proactive with Regular Maintenance
Regular inspections and preventive maintenance on your Ingersoll Rand SSR are the best ways to avoid unexpected pressure issues. Keeping filters, valves, and separators in good shape helps your compressor perform at its best and protects your production schedule.
For a broader look at pressure issues on different compressor types, check out our full troubleshooting guide here.