Pentair FLECK 5600 SXT Installer Manual page 31

Note
Multiply the amount of salt in kg by 3 to get a approximation of the brine volume to draw.
To calculate slow rinse duration:
The volume of water to be used for slow rinse is given in the resin manufacturers specifications.
Generally speaking, it is advised that between 2 and 4 BV of water is used to perform the slow rinse
after brine draw. The slow rinse cycle allows brine to be pushed slowly through the resin bed, allowing
the resin to be in contact with brine for sufficient time and therefore to be regenerated.
Refer to the injector curve at the common working pressure to determine the slow rinse duration.
T = (N x BV) / Q
slow_rinse BV
To calculate fast rinse duration:
The fast rinse is aimed at eliminating an excess of salt in the resin bed and also recompacting the
resin in the tank.
Depending on the valve type, the fast rinse flow rate is controlled by the DLFC or it has about the same
flow rate as in service. The fast rinse velocity can be the same as the service velocity, and the volume
of water to be used for the fast rinse is generally between 1 and 10 BV depending on the salt dosage.
T = (N x BV) / Q
fast_rinse BVfr
To calculate the refill duration:
The refill flow rate is controlled by the refill controller (BLFC). The relation between the BLFC size,
the tank size and the resin volume is given in the valve specifications.
To calculate the refill duration:
T = V / Q
refill WB BLFC
Note
When calculating the time required to draw the brine, take into account that the volume of
brine will be 1.125 bigger than the water refilled.
Ref. MKT-IM-013 / A - 21.12.2016
SR
DLFC
Installer Manual Fleck 5600 - SXT - System sizing
with:
T : slow rinse duration [min]
slow_rinse
N : number of BV
BV
BV: bed volume [L]
Q : injector slow rinse flow rate [L/min]
SR
with:
T : fast rinse duration [min]
fast_rinse
N : number of BV for fast rinse
BVfr
BV: bed volume [L]
Q : drain line flow controller size [L/min]
DLFC
with:
T : refill duration [min]
refill
V : Volume of water to be refill to prepare the brine [L]
WB
Q : BLFC flow rate [L/min]
BLFC
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