Steps below are ranked in order of increasing effectiveness as well as time consumption. If you have a severe clog (i.e., no reading at all), you might consider skipping directly to step 4 or 5.
Run Cleaning Cycle with Cleaning Solution in Cup 5
Run Cleaning Cycle with Coulter Clenz Solution in Cup 5 (Coulter Clenz is in a box on the lowest shelf of the right-most bench in the cold room)
Flush with tubing connected to Coulter Clenz instead of sheath fluid (i.e., pour Shutdown Solution back into its own box; refill bottle with Coulter Clenz, and connect to tubing)
Shut down the system with Coulter Clenz instead of the regular Shutdown Solution, leave the system off for 10-15 min, and turn system back on as usual
DO NOT shut down the system with Coulter Clenz unless you plan to turn it back on within 30 min. The detergent will corrode internal tubing if left in the system.
While trying to clear clogs, you may want to use fluorescent flow beads instead of your cell sample for testing. Flow beads are in a Beckman Coulter box on the right side of the main 4C fridge, second shelf from the bottom. Make sure you shake the vial to resuspend the beads before use. Run the "Flow Check 1" protocol under "Yvonne", and the various signal distributions should fall within the pre-drawn gates.