Spectra Watermakers Bimini 300, Installation And Operating Manual

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Bimini 300 Flow Test
The flow test is the most useful diagnostic test for system performance, and should be done before
replacing or cleaning your membrane. Changes in production or water quality are normally caused
by something
other than the membrane, unless the system has been left unused for a long time.
Before the flow test, change all filters and clean the sea strainer. Carefully check for water or air
leaks, as air in the system will cause low production and erratic salinity. Look for air bubbles in the
product flow meter, feed water hoses, and brine overboard hose.
Run the system and watch the feed pressure very closely. If the feed pressure to the Clark Pump is
asymmetrical from one stroke to another, this impedes performance. A difference of a few PSI is
acceptable, but anything over that is an issue. If the pump is asymmetrical, Clark Pump repairs
should be done before continuing with these tests.
If no asymmetry is noted, continue with this test.
You will need a graduated bucket, either a graduated pitcher or large measuring cup, and a stop-
watch. Log the voltage at the feed pump at the same time. Confirm at least 12.5 Volts at the Termi-
nal Block on 12
- Volt DC systems; 25 volts on 24 - Volt DC systems.
Take two measurements and compare them with the table on the following page. The first meas-
urement is the product flow alone. The second is the product flow combined with the brine dis-
charge flow to get the total flow or feed flow. You may take these measurements by two methods:
1. Time the product flow into a graduated pitcher, then divert both the product flow and brine dis-
charge together into a bucket, timing them to measure total flow.
OR
2. Divert the product flow into the pitcher while diverting the brine discharge into the bucket. Time
the flow of both at the same time. After calculating the product flow, pour the pitcher of product
into the bucket of brine to measure total flow.
The ratio of product flow to total flow gives us our recovery rate, as a percentage. If the percentage
is below the minimum it indicates an internal leak in the Clark Pump.