IR P185 & XP175 Troubleshooting: Regulation System Issues

Troubleshooting the Ingersoll Rand P185: Regulation System Problems

This guide covers common issues and solutions for Ingersoll Rand portable compressors—including models P185A-SJD, P185A-WJD, XP175A-SJD, and XP175A-WJD. The regulation system keeps everything running smoothly—until it doesn’t. If you’re seeing performance issues like surging engine speeds, incorrect pressures, or a safety valve that won’t stop popping off, this post will help you pinpoint the problem and fix it fast—no service call required.

1. Air Discharge Capacity Is Too Low

Causes:

  • Regulation set improperly
  • Main unloader spring has failed

Solution: Double-check your regulation settings. If the main unloader spring is worn or broken, it won’t respond to control pressure changes as it should.

2. Cannot Obtain Correct Engine Speed

Causes:

  • Regulator valve set too low
  • Plugged regulator bleed orifice
  • Plugged regulator bleed orifice silencer
  • Debris in regulator valve

Solution: Remove and inspect the regulator valve and bleed orifices. Clean or replace any components showing signs of clogging or buildup.

3. Unit Will Not Unload

Causes:

  • Regulator valve set too high
  • Blocked inlet to regulator valve
  • Ruptured regulator diaphragm
  • Leaks in regulation hoses
  • Ruptured unloader diaphragm

Solution: Start by adjusting the regulator. Then inspect hoses and diaphragms for leaks or rupture. Clear any blockages at the regulator inlet.

4. Oil Consumption Is Too High

Cause: Operating pressure is too low.

Solution: Increase the pressure setting to within spec—low operating pressure can prevent oil from returning properly through the scavenging system.

5. Excessive Carryover of Oil Into Air Discharge

Cause: Operating pressure is too low.

Solution: Similar to above—verify and adjust your regulator to increase system pressure within the manufacturer’s recommended range.

6. Compressor Is Overheating

Cause: Operating pressure is too high or too low.

Solution: Stay within the proper pressure window to avoid stressing the compressor and oil system. Too much pressure builds excess heat; too little can lead to poor cooling circulation.

7. Safety Valve Popping Off

Possible Causes:

  • Operating pressure is too high
  • Regulator valve set too high
  • Blocked inlet to regulator valve
  • Ruptured regulator diaphragm
  • Leaks in regulation hoses
  • Ruptured unloader diaphragm

Solution: Inspect the regulator settings first. Then check for diaphragm issues or blockages in the regulation line.

8. Surging Engine Speed

Causes:

  • Orifice in regulator valve is too small or restricted
  • No tension on inner spring in engine speed control
  • Broken engine speed control springs

Solution: Clean out the regulator orifice. If the engine speed fluctuates wildly, inspect the control springs and replace if worn or broken.

9. Start Pressure Is Too High

Causes:

  • Blocked inlet to regulator valve
  • Ruptured regulator diaphragm
  • Leaks in regulation hoses
  • Ruptured unloader diaphragm

Solution: Clean the regulator inlet and replace any ruptured components. Leaks in hoses can also create false pressure readings during startup.

Disclaimer: The information provided in this blog is intended for general troubleshooting guidance only and may not cover every situation or machine configuration. Always refer to your specific equipment’s manual and follow the manufacturer’s safety instructions. If you are unsure or uncomfortable performing any maintenance or repairs, consult a qualified technician. Air Compressor Services is not responsible for any injuries, damages, or losses resulting from the use of this information.