CR1 Filter Priming: Required Before Installation
The PUR CR1 filter (CRF950Z) must be primed before installation in any PUR dispenser. Hold the filter under cold running tap water for 10 seconds. This saturates the activated carbon and ion-exchange resin media and flushes loose carbon fines from the manufacturing process. Insufficient priming causes the first pour to contain visible black particles -- these are harmless activated carbon fines but are unacceptable in drinking water. After priming, shake the filter once to remove trapped air and snap it into the dispenser reservoir housing until the filter locks into place (you will feel a click or see the filter seat flush with the housing lip).
DS-1800Z First Fill: Top Tank to Filtered Storage
After installing the primed CR1 filter in the DS-1800Z upper reservoir, fill the upper reservoir to the maximum fill line with cold tap water. Do not use warm or hot water -- warm water increases flow rate through the filter but reduces contaminant contact time with the media, degrading filtration performance. Allow the water to filter through completely into the lower storage section. Discard the first full filtered batch by opening the front tap completely and draining into the sink. This first-pass flush removes any remaining manufacturing residue. Refill the upper tank and filter a second batch -- this water is safe for consumption.
Filter Status Indicator Setup
PUR DS-1800Z and DR Series dispensers include a built-in electronic filter change indicator that tracks filtered volume. After installing a new CR1 filter, reset the indicator by pressing and holding the filter change button for 3-5 seconds until the indicator changes from red to green. If you do not reset the indicator after filter replacement, it will show an incorrect filter life countdown and may prompt replacement before the filter is actually exhausted (or allow continued use past the replacement point). Reset the indicator every time you install a new filter.
Dispenser Tap and Reservoir Cleaning
PUR recommends cleaning the DS-1800Z reservoir and tap assembly monthly to prevent biofilm accumulation in the filtered water storage section. Remove the filter before cleaning -- do not expose the CR1 filter media to soap or cleaning agents. Wash the upper and lower reservoir sections with mild dish soap and warm water, rinse thoroughly, and allow to air dry before reinstalling the filter. Clean the front tap spigot by soaking in white vinegar for 15 minutes, then rinse with fresh water. Soap residue in the filtered water storage section will be absorbed by the CR1 filter media and cause off-taste in subsequent filtered water draws.
Troubleshooting Slow Flow Rate
Slow filtration through the DS-1800Z is the most common user complaint. Causes in order of frequency: (1) filter was not primed adequately -- reprime by soaking the filter in cold water for 15 minutes rather than the 10-second rinse; (2) filter media is clogged with sediment from turbid tap water -- install a pre-sediment filter cup above the CR1 if your tap water contains visible particles; (3) the filter has exceeded its 40-gallon rated capacity and the media is compacted -- replace with a new CR1. A new, properly primed CR1 filter in the DS-1800Z should filter one full upper reservoir load in 10-15 minutes.