System Regeneration Cycle (8-Cycles Operation) - Pentair Autotrol 255 Installer Manual

3.5.

System regeneration cycle (8-cycles operation)

Service (downflow) — cycle C0
Untreated water is directed down through the resin bed and up through the riser tube. The hardness
ions attach themselves to the resin and are removed from the raw water being exchanged on the resin
beads towards sodium ions. The water is conditioned as it passes through the resin bed.
Backwash (upflow) — cycle C1
The flow of water is reversed by the valve and directed down the riser tube and up through the resin
bed. During the backwash cycle, the bed is expanded and debris is flushed to the drain, while the
media bed is remixed.
Brine (downflow) — cycle C2
The controller directs water through the brine injector and brine is drawn from the brine tank. The
brine is then directed down through the resin bed and up through the riser tube to the drain. The
hardness ions are displaced by sodium ions and are sent to the drain. The resin is regenerated during
the brine cycle. When the air check valve closes brine drawing finishes, and then the slow rinse phase
starts.
Slow rinse (downflow) — cycle C3
Repressurize cycle (hard water bypass flapper open) — cycle C4
This cycle allows the air and water to hydraulically balance in the valve before continuing the
regeneration.
Fast rinse (downflow) — cycle C5
The controller value directs water down through the resin bed and up through the riser tube to the
drain. Any residual brine is rinsed from the resin bed, while the media bed is re-compacted.
2nd Backwash (upflow) — cycle C6
2nd Fast rinse (downflow) — cycle C7
Brine refill — cycle C8
Water is directed to the brine tank at a rate controlled by the refill controller, to create brine for the
next regeneration. During brine refill, treated water is already available at the valve outlet.
Note
For illustration purpose only. Always verify inlet and outlet marking on the valve.
Ref. MKT-IM-021 / A - 20.02.2019
Installer Manual 255/LOGIX 742-762-764 - Description
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