Spectra Watermakers VENTURA 150, Installation And Operation Manual

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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 period of 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 could be part of the problem.
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.
Make sure the ShurFlo overpressure cutout switch (PL - PMP - SFPH) is set to 125 PSI. With the
pump running, close the brine discharge thru - hull or kink the brine discharge hose. The feed
pressure should rise to 125 PSI, then the pump should shut off. If the pump shuts off at a
lower pressure see Adjust ShurFlo Pressure Switch on page 51.
You will need a graduated bucket, either a graduated pitcher or large measuring cup, and a
stopwatch. Before the flow test, change all filters and clean the sea strainer. Log the voltage at
the feed pump at the same time. Confirm at least 12.5 Volts at the feed pump 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
measurement is the product flow alone. The second is the product flow combined with the
brine discharge 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 discharge together into a bucket 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. 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.
Ventura Flow Test