LI-COR Environmental NewsLine

LI-6400 CO2 Injector Maintenance

One of the most frequent maintenance issues encountered at LI-COR is clogging of the 6400-01 CO₂ Injector filters due to oil present in the CO₂ cartridges. There are a number of brands of CO₂ cartridges; some have more oil present than others. When using cartridges supplied by LI-COR, we recommend that you inspect the filter after using 25 CO₂ cartridges. With other brands of cartridges (e.g. Crossman, Copperhead) you may need to inspect the filter after using a single cartridge, as they contain more oil. Replacement filters are available from LI-COR under part number 301-04472. In an emergency, you can also use a cigarette filter; remove the paper from around the filter and discard.

Figure 1 shows the location of the filter; unscrew the filter cap to access the filter. Follow these steps to verify the operation of the CO₂ Injector:

1. Remove the filter and inspect; replace if contaminated with oil.
2. Inspect the O-rings, both on the CO₂ piercing block, and on the back of the CO₂ source mounting block, where it attaches to the LI-6400 console. Replace if damaged or contaminated with oil.
3. Install a fresh CO₂ cartridge.
4. Check for flow by placing your finger over the small hole in the back of the source mounting block for about 5 seconds. Listen for a slight “pop” when you remove your finger.
5. Install the CO₂ Injector on the LI-6400 console.
6. Take measurements as per usual.
7. When finished for the day, remove the CO₂ Injector from the console to prevent CO₂ from leaking into the system and saturating internal components.

Figure 1. 6400-01 CO₂ Injector filter location.

Tags: CO2, LI-6400XT, maintenance

This article was originally posted on Saturday, October 6th, 2007.