Controls

• Auto: Press once to pull up start screen. Press Enter at Start Autorun to start the autosampler. The autosampler usually starts at the first vial position (says 1 at the bottom of the slot on the tray).
• Pause/Stop: Press once to pause after it finishes desorbing the sample. Press twice to stop the autosampler mid-run.
• Method: Press once to pull up the method settings. You can switch methods from here (soil only). Go to Edit Method to adjust method settings (mostly going here to edit desorb time and preheat temperature).
• System: Press once to pull up system settings. The only settings you really need to touch here are Calibration and Settings (arrow buttons up or push Enter to switch lines).

Preheat Temperature

When running ICAL, we set this to 40°C (I set it to 45°C because I think 40°C is a bit too low to properly visualize the alcohols and ketones). Officially, this temperature is supposed to remain constant for the duration of the ICAL. When ketones, TBA, oxygenates, or 1,4-dioxane are failing high/low in QC, you can lower/raise the preheat temperature to affect the recoveries. You don't need to restart from tune check if you do this, but it may take one cycle or so for the temperature to adjust. Raise/lower the temperature by about 3-4 degrees at a time.

Settings - Temperature

Here we can lower the temperature settings on the autosampler if we need to perform maintenance (removing purge needle or changing transfer line). Go to System > Settings and lower the US Probe Temp, XFER Line Temp and US Valve Temp to lower the temperature of the needle and the transfer line going from the autosampler to the concentrator.

Each instrument is (supposed to) have a sheet with the instrument parameters written on it for reference. This sheet contains all the temperature and time settings for the autosampler and the concentrator. If you forget the original temperature settings for the autosampler, you should be able to reference this sheet.

Calibration

We recalibrate the autosampler when it's not moving to the correct position to grab vials. Follow the prompts starting from Vial Pos 22 until you finish Equilibrium Block. When you see the screen showing you the number of steps taken, press 7 to retrain the steps until you get a consistent value at least three times. If the steps keep jumping everywhere after retraining, there might be a problem with the autosampler. Inform the supervisor.

Troubleshooting

When there are problems, always make sure to write down the specific error message in the instrument log and take a photo of the exact position the autosampler stopped. This information helps the technician (Naryan) identify the problem more easily.

Stuttering when grabbing vial

Sometimes the autosampler gripper doesn't slide smoothly along the rails when moving to grab the next vial. When this happens, it helps to wet a Kim wipe with methanol and wipe down the rails a few times. You can also get a bottle of lubricant from the bottom drawer under F3 and apply a bit of it to both ends of the sliders. Recalibrate after doing this.

Consistent jammed vial/low helium error

Try changing the gripper because the gripper sensor might be dying. Extra grippers are kept in the same drawer as the lubricant. To remove the gripper:

1. Pull the gripper block out so you can reach behind it to remove screws.

[pic of gripper block positioned for removal]

2. Get a Philips screwdriver and Allen keys (hex wrench). Remove the screws holding the gripper in place on top and behind. Disconnect the cables from the board. Be sure not to drop parts when removing the gripper (especially when loosening the hex screws because this holds the gripper in place so removing these causes the whole thing to fall down).

There is a spring between the gripper and the gripper block that allows the gripper to grab vials. This part tends to fall off when you remove the gripper, so check the vial tray afterwards to see if it fell in one of the slots.

To replace the gripper, repeat the steps in reverse. I find it easier to start by reinserting at least two of the hex screws to secure the gripper in place, then do the rest. Make sure the spring is between the gripper and the gripper block. Without the spring, the gripper won't be able to firmly grasp vials.