Installer manual Fleck 2850 SXT - System sizing
Ref. MKT-IM-030 / C - 12.05.2020
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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
fast rinse
= (N
BVfr
x BV) / Q
DLFC
with:
T
fast rinse
: fast rinse duration [min]
N
BVfr
: number of bed volume for fast rinse
BV: bed volume [L]
Q
DLFC
: drain line flow controller size [L/min]
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
refill
= V
WB
/ Q
BLFC
with:
T
refill
: refill duration [min]
V
WB
: Volume of water to be refill to prepare the brine
[L]
Q
BLFC
: BLFC size [L/min]
V
WB
= D
Salt
x BV / S
sol
with:
V
WB
: Volume of water to be refill to prepare the brine
[L]
D
Salt
: Salt dosage per litre of resin [g/L]
BV: Bed volume [L]
S
sol
: 360g/L - Solubility of salt per litre of water
Tip
When calculating the time required to draw the brine, take into account that the volume
of brine [Vbrine] will be 1.125 bigger than the volume of water refilled !
4.3
Salt amount definition
The salt settings are controlled through the controller programming. See Resin exchange capacity
and capacity of the unit [
4.4
Injector flow rates
The following graphics represent the injectors flow rate as a function of the inlet pressure for the
different injector sizes.
