EQUIPMENT INSTALLATION
System Regeneration Cycles
1. 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 water. The water is
conditioned as it passes through the resin bed.
2. Backwash (Upflow) — Cycles C1, C6:
The flow of water is reversed by the control 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.
3. Brine/Slow Rinse (Downflow) — Cycles C2, C3:
The control directs water through the brine injector and brine
is drawn from the regenerant 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. Brine draw is completed when the air check closes.
4. Repressurize Cycle — (Hard Water Bypass Flapper
Open), Cycle C4:
This cycle closes the flappers for a short time to allow the
air and water to hydraulically balance in the valve before
continuing the regeneration.
5. Fast Rinse (Downflow) — Cycles C5, C7:
The control directs water down through the resin bed and
up through the riser tube to the drain. Any remaining brine
residual is rinsed from the resin bed.
6. Brine Refill — Cycle C8:
Brine refill occurs during a portion of the fast rinse cycle.
Water is directed to the regenerant tank at a controlled rate, to
create brine for the next regeneration.
SERVICE
BACKWASH
BRINE/SLOW RINSE
FAST RINSE
From Regenerant
Tank
To Regenerant
Tank
BRINE REFILL
REPRESSURIZE
C0
C1 and C6
C2 and C3
C4
C5 and C7
C8
Figure 1
Valve Features
Optical Sensor
One Piece Valve
Disc Spring
Refill Controller
Control
Module Mount
Check Ball
Injector and Cap
Regenerant Tank
Tube Connection
Manifold
Connection
Air Check
Right Side 255 Valve
Left Side 255 Valve
Motor
Camshaft
Backwash
Drain Control
Valve Discs
Locking Bar
Inlet
Drain
Injector Screen
Filter
Outlet
Figure 2 255 Valve Identification
AUTOTROL
®
740/760 Control 255 & Performa Series Valves (268, 268FA) Service Manual
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