Symptom: The dirty filter icon is shown.
Possible Cause: The filter boxes are dirty and clogged.
Slide the filters out of the Enclosure Exhaust. Clean the filters with soap and water. Put them back in the enclosure exhaust assembly.
Symptom: The Enclosure Exhaust does not remove coolant mist and smoke. The dirty filter icon is shown.
Possible Cause: The vacuum switch is defective.
A faulty vacuum switch may fail to notify you of a dirty filter, or may falsely indicate that the filters are dirty.
Disconnect the vacuum switch from the I/O PCB. Put a jumper on the vacuum switch connector pins on the I/O PCB. The connector is at P23 for CHC  and P34 for NGC .
Go to Enclosure Exhaust Clogged on the I/O tab of the Diagnostics screen. Verify the value changes state when you put the jumper on the pins. If the value changes state, replace the vacuum switch.
If the value does not change, check the cable for damage. If the cable is not damaged, go to I/O PCB - How it Works and Troubleshooting Guide (Classic Haas Control).
Symptom: The Enclosure Exhaust does not remove coolant mist and smoke.
Possible Cause: There is a problem with the fan, or with the power to the fan.
Clean the fan. Inspect the fan blades for damage. Make sure the fan turns by hand. If there is damage to the fan blades, or the fan does not turn by hand, replace the fan.
If the fan turns:
- Measure the spindle fan connector on the I/O PCB. The correct voltage is
Measure the voltage at P41 for machines with the Classic Haas Control (CHC) and at P32 on machines with the Next Generation Control (NGC).
If there is no voltage at the spindle fan connector, go to I/O PCB - How it Works and Troubleshooting Guide (Classic Haas Control).
- If there is 120 VAC at the spindle fan connection, measure the voltage at the end of the spindle fan cable 300A.
If there is no voltage at the end of the cable, replace cable 300A. If voltage is present, the fan is faulty.