Kenmore 625.385700 - Manual (Page 12)

- HOW YOUR REVERSE OSMOSIS SYSTEM WORKS
PREFILTER
Water from the cold supply pipe enters the RO as­
sembly prefilter first (Figure 10, page 10, and sche­
matic, page 13).
The prefilter has a replaceable sediment cartridge
with activated carbon in its composition. The car­
tridge (10 micron) removes sand, silt, dirt, other sedi­
ments, and up to the ppm of chlorine shown in the
specifications from the feed water (page 18). Chlo­
rine will destroy the RO membrane. Filtered, clean,
chlorine- free water flows from the prefilter, to the RO
membrane cartridge.
IMPORTANT: See prefilter maintenance, page 14.
REVERSE OSMOSIS (RO) CARTRIDGE
The RO cartridge is a tightly wound special mem­
brane. The membrane removes the dissolved solids
and organic matter when water is forced through the
cartridge. Fligh quality product water (about one
ounce per minute) exits the RO cartridge and goes to
the storage tank, or to the postfilter and RO faucet.
Reject water, with the dissolved solids and organic
matter, is routed through the flow control and to the
drain.
STORAGE TANK
The storage tank holds up to 2.3 gallons of product
water. A diaphragm inside the tank keeps water
pressurized to about 30 psi, when the tank is full, to
provide fast flow to the RO faucet. The tank, when
empty, is pressurized to 5 - 7 psi.
POST FILTER
After leaving the storage tank, but before going to the
RO faucet, product water goes through the post filter.
The post filter is an activated carbon type filter. Any
remaining tastes and odors are removed from the
product water. Taste-free, odor-free, clean, high
quality drinking water is available for use.
FAUCET
The sink or countertop faucet has a hand operated
knob to access drinking water. An air-gap is built
into the faucet drain water connection to comply
with plumbing codes.
FAUCET ELECTRONICS (UltraFilter 350)
The RO system will monitor the length of time the fil­
ters have been installed. The faucet has an indicator
light that flashes to inform you of the status of the fil­
ters.
Green - Filters are good. Red - Filters need to be re­
placed after 6 months of time has passed.
SHUTOFF ASSEMBLY
To conserve water, the drinking water system has an
automatic shutoff system. When the storage tank has
filled to capacity, and the drinking water faucet is
closed, pressure closes the shutoff to stop flow to
drain. Pressure in the storage tank is about half of the
water supply pressure. After drinking water is used,
and pressure in the system drops, the shutoff opens
to allow water flow again.
CHECK VALVE
A check valve (Figure 16) is located in the RO man­
ifold, above the center sump. The check valve pre­
vents a backward flow of product water from the
storage tank. A backward flow could rupture the RO
membrane.
FLOW CONTROL
Water flow through the RO membrane is regulated
by the flow control. It maintains the desired flow rate
to obtain the highest quality drinking water. The
flow control is located in the end of the 1 / 4" red drain
tubing, at the RO manifold drain port.
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Problems, Questions? Call 1-800-426-9345 Kenmore Water Line