User Guide

Maintance
The Caleffi NA573 assembly uses a special 10-inch cartridge insert, code NA573102, containing
the color changing resin beads necessary to demineralize water passing through it at relatively
low flow rates. The cartridge assembly can be isolated for replacement by closing the two ball
valves. The clear housing can then be unscrewed to remove and replace the cartridge. The Caleffi
cartridge will appear blue color when new. Its internal color will change to amber as the resin beads
approach a spent condition. Each cartridge can demineralize approximately 30 gallons of water.
This should provide several years of normal make-up water supply, assuming only minor water
losses from the system occur.
Maintenance and field testing procedures for the Caleffi 553 AutoFill fill valve and 573 series
back flow preventer can be found in instruction sheets 38467 and 38517, respectively, and
are
packed with these components unassembled in the box containing the NA573022 water
treatment filling unit. These instruction sheets are also available at www.caleffi.com.
Replacement of filter housing assembly
To prevent costly repairs or possible water damage, it is strongly recommended to replace every
5 years the clear plastic filter housing assembly, code NA573100. Be sure to date the newly
installed, or replaced, housing for future reference and indicate the next replacement date.
Replacement of demineralization cartridge
The 10-inch cartridge insert, code NA573102, containing the color changing resin beads that
demineralizes water passing through it, will appear blue color when new. The internal color will
change to amber as the resin beads approach a spent condition. Each cartridge can demineralize
approximately 30 gallons of water. This should provide several years of normal make-up water
supply, assuming only minor water losses from the system occur.