Ensure material flow is equally restricted on both material lines.
Ensure that the pressure imbalance value, on the Setup > Pressure/Flow screen, is at an acceptable maximum pressure to prevent unnecessary alarms and abort dispenses.
Check feed pump and hoses for blockage. Check that feed pumps have correct air pressure.
Check if heater and PRESSURE RELIEF/SPRAY valve are plugged. Clear/Replace rupture disk. Do not replace with a pipe plug.
Refill tanks/barrels with material