Hach-Lange SIGMA SD900 Refrigerated Sampler and All Weather Refrigerated Sampler User Manual - Manual (Page 83)

81
Maintenance
6.5 Desiccant replacement
A desiccant cartridge is located inside the controller to absorb
moisture and prevent corrosion. Over time the desiccant will
become saturated with moisture and should be replaced.
Monitor the desiccant color through the clear plastic window
(
Figure 37 ). The color will change from yellow to green when the
desiccant is saturated.
Prerequisites:
• Desiccant
• Silicone grease
Note: See Replacement parts on page 93 for ordering information.
Procedure:
1. Unscrew and remove the desiccant holder from the controller
( Figure 37 ).
2. Remove the plug from the end of the desiccant tube ( Figure 38 )
and discard the spent desiccant.
3. Fill the desiccant tube with fresh desiccant.
Note: Fresh desiccant should be yellow.
4. Replace the plug.
5. Apply grease to the O-ring ( Figure 38 ).
6. Replace the desiccant tube in the controller.
Figure 37 Side view of controller—pump and desiccant
1 Desiccant window 2 Peristaltic pump