When your Sullair compressor encounters an error during startup or operation, it will display a fault code or message to indicate that there has been an issue. This is a built-in function of Sullair compressors that can be useful when trying to identify the cause of an operational issue.

The main Sullair compressor fault codes that you will encounter are the P1 and P2 codes. These errors typically indicate some sort of voltage issue. There are several other possible Sullair compressor error messages that can encounter as well.

This guide will provide you with details on all the different Sullair compressor fault codes and error messages that you could possibly encounter while using your air compressor. This will help you quickly identify and resolve any issues that could be causing your Sullair compressor to not function properly.

Sullair Compressor Fault Codes Causes

Sullair compressor fault codes will be displayed anytime the system encounters some type of error that keeps it from running properly. The type of error that your system encounters can be identified by the fault code or error message displayed by your Sullair compressor.

These codes will be visible on the display menu controller and can be cycled through using the up or down buttons. Typically, the Sullair fault codes fall into one of two categories. These are unit faults and system faults.

Unit faults will result in a shutdown of the compressor and will indicate a potentially critical issue that you will need to resolve before using your Sullair compressor. System faults are generally software related and can be remedied without a complete shut down of the compression system.

These distinctions can help you determine whether you are experiencing a controller issue or an external one that is causing your Sullair compressor to not work properly.

Sullair Compressor Fault Codes Guide

The most common Sullair compressor fault codes that you will encounter are the P1 and P2 codes. These codes indicate a voltage issue that is keeping your Sullair compressor from receiving the proper amount of power to function.

That being said, there are several other error messages that you could see while owning your Sullair compressor. The next part of this guide will detail all of these fault codes and error messages in detail. This will help you better identify your issue so that you can address it properly.

You can consult your user manual for your Sullair compressor for even more information regarding these fault codes and error messages.

P1

The P1 fault code indicates a loss of transducer inputs during the run phase of your compressor. This means that your Sullair compressor has experienced some time of voltage issues while operating. To resolve this, you should check your voltage source and reground the connection.

The P1 fault code will typically result in a complete shutdown of your Sullair compressor. You will need to address the issue before you will have full functionality of your air compressor.

P2

The P2 fault code is another indicator that your Sullair compressor is experiencing grounding or voltage issues. If during the run phase of your compressor, it begins to experience power issues, you will likely be shown the P2 fault code.

You should inspect your voltage source and ensure that it is properly grounded before attempting to operate your Sullair compressor. The P2 fault code will result in a complete shutdown of the compressor.

Low Fuel Level

The low fuel level error message will display on your Sullair compressor whenever you attempt to start or operate the compressor with inadequate fuel supplies. This error message will typically result in your compressor shutting down or not starting properly.

You will need to add an appropriate amount of fuel to your Sullair compressor before attempting to run the machine. Once you have added fuel, this error message will disappear and your compressor will run like normal.

Comp High Temp

The comp high temp error message will display on your Sullair compressor whenever the temperature of the machine becomes too high. This is typically caused by fan slippage, thermostat malfunctions, or a damaged cooling unit.

To ensure that the temperature of your Sullair compressor is brought down to an acceptable level for operation, you should clean the cooling unit, check the fan belt tension, and replace any broken thermostat currently installed on your compressor.

Once your Sullair compressor has been brought down to the acceptable temperature range between 50 degrees Celsius and 150 degrees Celsius, this error message will have been resolved. This error message will result in your compressor shutting down or starting properly.

RTT High

The RTT High error message will be displayed whenever the RRT switch that is normally closed has been opened for some reason. The RTT switch, or receiver tank temperature, manages temperature parameters within your compressor.

You will need to replace any faulty RTT switch installed in your compressor if you are seeing this error message frequently. The RTT High error message will cause your compressor to shut down and not start up properly.

Primary Shutdown

The primary shutdown error message is caused by module malfunctions within your compressor. This error message indicates issues that will cause your compressor to shut down and not power up properly. Dirty air filters are another main cause of the primary shutdown error message.

To resolve this, you will need to check the voltage source and ground of the connection. You should also visually inspect the compressor and power source for any damage. Finally, you should inspect and replace any dirty filters that could be causing problems for your air compressor.

WL Comm Error

The WL Comm Error message will display whenever the Sullair compressor detects a loss of communication with the warning bank module. This will cause your error message system to not work properly.

To resolve this issue, you should check the single axle controller and make sure that all of the gauges and warning bank connectors are connected properly. You will experience shutdown and startup issues with your compressor until this issue is resolved.

Engine Overcrank

The Engine Overcrank error message will appear whenever the Sullair compressor detects that the maximum number of engine crank cycles has been exceeded. This error message will result in your compressor shutting down during operation.

To resolve this error message, you will need to check the battery and voltage source for your compressor.  You should also check the starter relay for a short in the grounding. It is also important that you inspect the source voltage powering the starter relay of your compressor.

High Comp Pressure

The High Comp Pressure error message will be displayed whenever the Sullair compressor detects pressure levels that exceed safe and acceptable levels. This can be caused by improper calibrations of the compressor at setup.

To resolve this issue, you should wait for the psi to fall below 10. Once you have let the psi levels fall below 10, you should recalibrate your transducers using a gauge calibration tool and routine. Your compressor will not start properly until you resolve the pressure issues causing this error message.

Eng Speed Too Low

The Eng Speed Too Low error message will display anytime the Sullair compressor detects that the engine speed has dropped below the preset values for longer than is acceptable. This measure is put in place to help protect the rubber drive coupling between the engine and the compressor.

To resolve this issue, you should check your fuel levels and add some if you find that it was close to empty. You should also check the inlet valve for any opening during the warm-up phase of your compressor’s startup process.

Oil Pressure Low

The Oil Pressure Low error message will display whenever the Sullair compressor detects oil levels that are below the minimum required for operation. This will not result in a shutdown of the machine but you should consider checking the oil levels and filling them up to an acceptable level to resolve this message.

Engine Overspeed

The Engine Overspeed notification will be displayed anytime the Sullair compressor detects engine speeds that are above the acceptable limit. This will cause a warning on your Sullair display controller. You should immediately shut down your compressor and check for volatiles in the atmosphere when you see this message.

It is advised that you do not restart your compressor until you are able to resolve the issue causing your engine to operate faster than it should.

Final Thoughts

This guide has provided you with all of the information that you need to better understand the different Sullair compressor fault codes and error messages. This will be valuable information when trying to determine the exact cause of your issues so that you can address them properly.

The fault codes and error messages included and detailed in this guide can be experienced on most models of Sullair compressors. You should use this information the next time you receive a fault code or error message on your compressor.