5.1 Air Compressor Troubleshooting

Haas Air Compressor - Troubleshooting

Revision A - 04/2025

Overview

This chapter provides a basic troubleshooting guide for both the single speed and variable speed Haas Air Compressor.

This guide includes a table of common issues with the compressor as well as potential solutions.

This image shows the flow of the oil and air through the internals of the compressor system.

  1. Air Intake Filter
  2. Inline Induction Motor
  3. Screw Compressor Assembly
  4. Air-Oil Separator Unit
  5. Oil Separator Element
  6. Safety Valve
  7. Hot Compressed Air Entering Radiator
  8. Cool Compressed Air Leaving Radiator
  9. Hot Compressed Oil Entering Radiator
  10. Cool Compressed Oil Leaving Radiator
  11. Oil Filter

Air Compressor - Symptom Table

Symptom Possible Cause Solution
There is a low voltage alarm Voltage may have temporarily dropped below the lower limit Cycle power on the compressor. Disconnect from the power supply and wait 3 minutes before reconnecting. 
The 1689 password isn't working to change any user settings The password is set to a different 4 digit code. Use the 1688 password. Refer to the Compressor Settings - Passwords section below for more information on what menus need the password as well as how to change the password.
There is an alarm for the oil schedule alarm The oil hasn't been changed according to the schedule or the scheduled interval hasn't been reset See the operations chapter of the manual for how to clear the oil schedule alarm.
There is oil coming out of the air intake while the compressor is unloading.  There are multiple air compressors connected in the system. The pressure created by the other air compressors is pushing air backwards through the air compressor.  Make sure the compressors are set to the same working pressures. Place a check valve on the outlet line to prevent air backflowing from the outlet line through the compressor system. 
The temperature of free air delivery is too low The ambient temperature surrounding the compressor is too low Reduce the amount of heat dissipation in the compressor
The compressor has had no-loading running too long Increase the air supply
The temperature sensor is faulty Replace the temperature sensor
The temperature control valve is faulty Replace the temperature control valve
The compressor is experiencing unexpected shutdowns due to high temperature of air delivery The compressor doesn't have enough oil Check the oil level. Add oil if level is low
The ambient temperature surrounding the compressor is too high Provide better ventilation for the air compressor
The radiator is dirty causing inefficient cooling Clean the radiator unit
The wrong oil type is being used in the compressor Check the oil specification and replace the oil with the correct oil. Recommended oil is Rarus 427
The temperature control valve is faulty Replace the temperature control valve
The oil filter is clogged Replace the oil filter
The temperature sensor is faulty Replace the temperature sensor
There is smoke coming out of the air intake filter, the compressed air has a high oil content The compressor has too much oil Check the oil level. Remove some oil as needed
There is a blockage in the oil return pipeline Clean out the oil return pipeline as much as possible
The free air delivery pressure is too low Adjust the working pressure range
Oil-Air separator is not functioning properly Replace the Oil-Air separator unit
The pressure regulator spring is loose  Replace the pressure regulator unit
The compressor won't run when full-loading The tolerance valve is faulty Reset the tolerance valve
The intake valve is not working properly Clean the intake valve and add grease to it
The oil throttle cylinder is not working properly Check the oil throttle cylinder. Clean or replace the cylinder as needed
There is a leak in a pipeline or fitting Check the fittings and pipes for leaks
The Oil-Air separator unit is clogged Replace the Oil-Air separator unit
The compressor has smoke coming out of the air intake filter The air intake valve has a leak Replace the intake valve
The oil return pipeline is blocked Clean the oil return pipeline as much as possible
The pressure regulator valve has a leak Replace the faulty pressure regulator valve
The discharge valve is not working properly Replace the discharge valve
The Oil-Air separator unit is not working properly Replace the Oil-Air separator unit

Compressor Settings - Passwords

There are multiple passwords that allow you to access different menus on the interface.

The image shows which passwords can be used to access the menu:

  1. USER PARA - 1689 [1]
  2. FACT PARA - 1689 [1]
  3. CONFIG PARA - 1688 [2]
  4. VSD SET - 1688 [2]
  5. SCH PRES - 1689 [1]

Note: Some of these menus contain parameter values set specific to each unit. Before any of these parameters are adjusted, record the original value so that you can change the value back.

Changing User Password

If the 1689 password doesn't work for any of the menus pointed out above, use the 1688 password.

Open the USER PARA menu and press the down button until you see the User Password option [1]. Click on it and enter the current password [2] to gain access to change it.

Once you enter the current password, enter what you want the new password to be and press enter.

Note: The password you entered can then be used to make changes in the USER PARA menu.

Changing Factory Password

If the 1689 password doesn't work for any of the menus pointed out above, use the 1688 password.

To reset the password you can go to the FACT PARA tab and use the 1688 password. 

Press the down button until you see the Factory Password2 option [1]. Set the password to the 4 digit code that you want.

Note: The password you set can now be used to enter the FACT PARA menu.

5.2 Compressed Air Dryer Troubleshooting

Compressed Air Dryer - Troubleshooting

Revision A - 04/2025

Overview

This image shows the flow of the air through the internals of the air dryer system. This can be used to help diagnose alarms or issues with the air dryer.

Compressed Air Dryer - Symptom Table

SYMPTOM POSSIBLE CAUSE SOLUTION
The working pressure of the air dryer is much different than the working pressure of the air compressor The valves are not open completely Make sure that the pipe valves are fully open
There is some leakage coming from the pipe connectors Check the connectors and valves in the pipelines for leaks
There is excessive moisture in the compressed air The air bypass valve is not closed completely Make sure that the air bypass valve is fully closed
The compressed air is not circulating through the air dryer Make sure that the inlet port to the dryer and the outlet port from the dryer are open
The auto drainer is not working properly Clean the auto drainer or replace if not functioning
The air dryer will not power on, even when the air compressor can power on The air dryer power cable is broken Check the cable connector for continuity and the connectors for damage. Replace the cable if needed
The fuse is burned out Check the short circuit fuse
The air dryer display is showing fault code A11 The system is low on refrigerant Add refrigerant to the dryer.
The air dryer display is showing fault code A21 The dew point sensor is causing the alarm Check if the dew point sensor needs to be replaced.
The air dryer display is showing fault code A22 The condensation sensor is causing the alarm Check if the condensation sensor needs to be replaced
The air dryer display is showing fault code A31 The dew point is set too high for the conditions Check that the dew point is correct. If it is too high, lower the dew point or wait for ambient conditions to change.
The air dryer display is showing fault code A32 The temperature of the condensation is too high Determine if the temperature can be lowered