AmeriWater MRO3, Operation & Maintenance Manual

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MRO 3 & 4 MANUAL
25
98-0140
Rev. F
5.4 MEMBRANE FLUSH FEATURE (AUTO FLUSH)
The MEMBRANE FLUSH FEATURE is the preferred means for minimizing bacterial growth
for the MRO3 or MRO4 during periods of low water usage. Ordinarily these sizes of MRO
are connected to a loop or storage tank only having 1-2 days of non-use when dialysis
procedures are not being carried out. The MRO3 or MRO4 can be set up to discourage
microbiological growth by “flushing” periodically.
The Membrane Flush feature is disabled as a default from the factory. To enable this feature,
set the following setpoints on the MRO controller accordingly (See Section 6):
SETPOINT SETTING
Flush Type 6
Flush Time 15 to 45 (minutes)
Flush Interval 4 to 12 (hours)
Flush Mode 3 or 4
FLUSH MODE RO PUMP INLET VALVE DIVERT VALVE
3
For storage tank applications
ON OPEN ENABLED
4
For loop applications
ON OPEN DISABLED
FLUSH MODE #3 assumes that the MRO is connected to a storage tank and, therefore,
will divert the PRODUCT WATER to the drain. This minimizes bacterial growth and directs
all the water to the drain, rather than refill the storage tank.
FLUSH MODE #3 will cause all
the water to be diverted to drain for each MEMBRANE AUTO FLUSH cycle.
On the other hand, when an MRO is connected to a Direct Feed Loop , the PRODUCT
water should be directed into the loop during the MEMBRANE AUTO FLUSH cycle to keep
the water in the loop “fresh”. Setting the
FLUSH MODE for #4 will disable the DIVERT TO
DRAIN feature, and the PRODUCT WATER will be circulated through the loop during each
MEMBRANE AUTO FLUSH cycle. The MEMBRANE AUTO FLUSH will operate while the
MRO is in the STANDBY mode, while connected to the loop even though no water is being
used for dialysis.
The MRO must be connected to the electric power source, incoming water supply, and drain
at all times for this feature to be operable.
The Flush Time and Flush Interval settings are recommended settings, but may be adjusted
to fit your specific needs. Contact your AmeriWater representative for guidance.
Before determining a bacteria count, the MRO should be run for 5 minutes with the REJECT
VALVE in full flow, then placed in OPERATE for 5 – 10 more minutes after a period of non-
use, but before taking a sample of the PRODUCT WATER. Bacteria are known to increase
in population when water is not moving.