Filter Cartridge Replacement - Pentair BIG BLUE20 Manual

When To Change The Cartridge
The life of the cartridge depends on the water volume used
and the substances in the water. Normally the cartridges
should be changed at every 6 months or less. Replace the
cartridge sooner if the water pressure at the faucet begins
to drop noticeably or if you notice changes in the taste,
color or flow of filtered water.

Filter Cartridge Replacement

A. Turn off water supply to filter. Depress red
pressure-relief button on top of filter. Use housing
wrench to unscrew bottom of housing. Turn
slowly to the left and support the housing and
piping as you loosen the housing.
Note: If turning off water supply to the filter will
also turn off water supply to the rest of the home,
be sure to fill bucket of water first to allow you to
clean the housing after it has been removed.
B. Pour out the water from the housing and remove
and discard the old cartridge. Locate and remove
large O-ring, wipe clean of lubricant. Rinse out
bottom of housing and fill about 1/3 full with
water. Add about 2 tablespoons of bleach and
scrub cap and bottom of housing with non-
abrasive sponge or cloth. Rinse thoroughly. Check
O-ring for damage. If cut, scratched or stretched,
replace it with a new one. If the O-ring is in good
condition, lubricate it with clean silicone grease,
insert it back into groove and smooth into place
with finger. Insert new cartridge over standpipe in
bottom of housing.
C. Screw bottom of housing onto the cap and hand-
tighten (DO NOT OVER TIGHTEN). Turn on
water supply slowly to allow filter to fill with
water. Depress rea pressure-relief button to release
trapped air. Check for leaks before leaving
installation.
NOTE: After installation, flush the cartridge for 10
minutes, wait one hour, and then flush again for 10 minutes
before using the water.
NOTE: Use only PENTAIR replacement cartridges for
best results. Failure to use so, will void your warranty.