Initial installation -- ISH-200 and ISH-100
The Culligan ISH-200 ships with the KDF-55 filter cartridge pre-installed inside the showerhead body. Remove the existing showerhead. Apply 3 wraps of Teflon tape clockwise around the shower arm threads. Thread the Culligan showerhead clockwise onto the arm by hand until snug. Use a wrench (cloth-protected) for one quarter-turn additional. Turn on the water and check for drips at the arm connection. The filter cartridge begins working immediately upon first use -- no soaking or priming required.
First-use flush
Run the shower on full flow for 2-3 minutes before first use. This flushes any loose media granules or manufacturing residue from the filter cartridge. The water may run slightly discolored (grey or brown) during the first 30-60 seconds -- this is fine. Discoloration should clear fully within 2 minutes. If discoloration persists beyond 5 minutes, remove and reinstall the cartridge (see cartridge replacement below) to verify correct seating.
Cartridge replacement -- IC-EFF-R
Replacement interval: 10,000 gallons or 6-12 months (whichever comes first). Signs the cartridge needs replacement: reduced spray pressure (filter media clogging), return of chlorine odor in the shower steam, or visible discoloration at the nozzles. To replace: (1) Unscrew the showerhead from the shower arm. (2) Locate the cartridge housing -- a small compartment in the upper body of the showerhead. (3) Unscrew the cartridge housing cap counterclockwise. (4) Pull out the spent cartridge. (5) Insert the new IC-EFF-R cartridge. (6) Replace the housing cap (hand-tighten -- do not over-tighten). (7) Re-attach the showerhead to the arm. (8) Run a 2-minute flush before use.
WSH-C125 in-line filter installation
The Culligan WSH-C125 in-line whole-body filter installs between the shower arm and the existing showerhead. Remove the existing showerhead. Apply Teflon tape to the arm threads and thread the WSH-C125 filter housing onto the arm. Apply Teflon tape to the filter output threads and re-attach the existing showerhead. The filter housing is transparent, allowing visual inspection of filter media condition. Replace the cartridge when the media darkens to brown (approximately 6-12 months).