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Boulder GNC Water Well recommends that most household filter cartridges should be change every 6 months, when your water pressure decreases, or when there are changes in taste, color or odor. We rate the difficulty of filter changes at an easy level but some mechanical knowledge is still necessary. Be aware that while changing filters, exposure of the water system to bacteria is likely, so sanitation is important. The following instructions are generic, and your system may be different then described.

  1. Turn off water supply to filter housing or if you have a Valve In Head unit rotate handle on top of filter housing to the off position and skip step 2.
  2. If your unit is not the Valve In Head there may be valves plumbed in front and behind it, that should all be closed.
  3. Depress Pressure release (typically a red button, if present) to relieve water pressure in filter housing. Note: it is normal for water to escape from the release at this time.
  4. Unscrew filter housing using a filter wrench or strap wrench (a large pipe wrench can be used but care must be taken not to damage the unit). Note: it is common for the o-ring in the filter housing to stick to the cap.
  5. Remove used cartridge and discard. Rinse out filter sump and fill about 1/3 full of water. Add about 2 to 3 tablespoons of unscented bleach and scrub thoroughly and rinse.
  6. Remove O-ring /gasket from sump (or cap) and clean grove and o-ring. Use a silicone grease to lubricate the o-ring. Replace o-ring in grove. Note: This step in important to ensure proper seal upon reassembly.

Caution: If O-ring is crimped or damaged contact Boulder/GNC Water Well for replacement O-ring.

  • Insert new cartridge into the sump making sure that the filter is centered and that the bottom of the filter is over the standpipe.
  • Screw the sump onto the cap and tighten by hand. Make sure the filter slips over the cap standpipe. Do not over tighten.
  • Turn on water supply to filter slowly to allow filter housing to fill with water. If using a Valve In Head, slowly rotate lever on top of the unit back to on (filter) position.
  • Depress the pressure relief button (if present) to release trapped air from the housing.
  • Check for leaks on the unit (also check any valves that you operated for leaks.)

Warning: Do not use with water that is microbiologically unsafe or of unknown quality without adequate disinfection before or after the unit.

Note: An activated carbon cartridge (taste/odor) may contain a small amount of carbon fines (very fine black powder) and a new cartridge, after installation, should be flushed with sufficient water to remove the fines before using the water. Each time you use water from your filtered water tap for drinking or cooking purposes, it is recommended that you run (flush) the tap at least 10 seconds prior to using water. This is particularly important if the water tap is not used daily.

Note: Certain types of harmless bacteria will attack cellulose material. Cartridges containing cellulose may seem to disintegrate, produce a "musty" or "moldy" odor, or form a black precipitate due to the bacteria. If you notice any of the above problems while using the cellulose media cartridges, switch to a synthetic media cartridge or with Boulder GNC Water Well.

Note: This replacement cartridge has a limited service life. Changes in taste, color and flow of the water being filtered are signals that replacement of the cartridge is, or soon may be, necessary.

Caution: Filter must be protected against freezing. Failure to do so may result in cracking of the filter and water leakage.

Caution: All filtration systems contain other parts that have a limited service life. Exhaustion of the service life of those parts often cannot be easily detected. Commonly, it is only after leakage has been observed or water damage has occurred that one is made aware that the service life has been exhausted.

Important Notice: To prevent costly repairs or possible water damage we strongly recommend that the bowl or sump of all plastic housings be replaced periodically: every five years for clear sumps, and every ten years for opaque sumps. If your sump has been in use for more then the recommended period, it should be replaced immediately. Be sure to date any new or replacement sump for future reference and indicate the next recommended replacement date.



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