Replacing the LI-830 or LI-850 Pump

The internal pump in the LI-830 and LI-850 gas analyzers will need to be replaced if it fails. This document describes how to remove a pump and install a replacement.

Components

The replacement pump kit is sold as part number 800-912. It includes the pump and hardware for the installation. Some of the parts may be installed on the pump.

Description	Part Number
Pump with tubing (1)	9980-067
Quick-connect coupler for ¼" tube (1)	300-03125
Quick-connect coupler, ¼" tube to 10-32 thread (1)	300-07474
Pump padding (1)	6568-342
Zip-ties (4)	218-08500

Removing the old pump

You'll need a #1 or #2 Phillips screwdriver and a utility knife or clipper. The installation may take an experienced technician about 30 minutes. If the instrument has been running, power if off and let it cool for 5 or 10 minutes before starting. To replace the pump:

Note: Be sure that you are properly grounded to avoid electrostatic discharge that can damage the electronics. Use an anti-static wrist strap, electrostatic discharge grounding mat, or occasionally touch bare metal that has a clear path to ground, such as an unpainted computer case.

1. Remove the top cover.
2. It is held in place by 6 screws on the top. Loosen the screws and slowly lift off the cover. Be careful not to strain the ribbon cable that connects to the top cover. You can disconnect the cable from the top cover if needed.
2. Unplug the pump wiring harness from the pump circuit board.
3. Cut the two zip-ties that hold the pump into the case.
4. Remove the tubes from the two quick-connect fittings.
5. Firmly press the orange collar toward the quick-connect fitting while pulling the tube out of the fitting.
5. Lift the old pump and zip-ties out.

Installing the new pump

1. Install the pump padding on the bottom of the new pump.
2. Remove the paper backing to expose the adhesive. Press the adhesive onto the new pump, as shown.
3. 
2. Mount the pump.
3. Begin by routing two zip-ties through openings in the mounting bracket and around the replacement pump. The pump installs with the padding down, in contact with the metal. Tighten the zip-ties to secure the pump.
4. 
5. 
6. Tighten them very tightly — for each zip-tie, grasp the end of the tie with a pliers and pull it tight. Cut off the extra length from the zip-ties.
3. Attach the pump tubes to the quick-connects.
4. Press each tube firmly into the fitting until it is fully seated in the fitting. Two replacement quick-connect fittings (300-03125 and 300-07474) are included with the kit, which can be used if your quick-connects have been damaged.
4. Reconnect the pump wiring harness to the circuit board.
5. 
5. Re-attach the case top cover.
6. Reconnect the display ribbon cable if you removed it. Tighten the six screws that hold on the top cover.

The pump replacement is complete. Power on the instrument and test the pump to be sure it is operating as expected.

Note: The pump will not run until the optical bench is warmed up, which may take a few minutes after powering on the instrument.

Resetting the pump hours

The instrument records the number or operating hours for the pump. You should reset this count after installing or replacing the pump. Connect with the instrument using the software and then click Settings > Diagnostics and click the gear button near Pump, and then reset the hours.