EcoWater CHC Series, Service And Troubleshooting Manual, Page: 57 / 130

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Bag Filters-
Many of the systems that contain a centrifugal separator also have a bag filter. This bag filter
is used to remove the lighter that water particles from the water stream. Some filters are in line
with the separator while others remove a portion of the filters flow in a side stream application.
In-Line Bag Filters
a. The inline bag filter housings are placed in line with the discharge flow from the
separator. As the bag starts to blind off (clog up) the overall pressure on the
separator’s discharge will increase until it reaches the set point (BELOW THE
PUMPS DH PRESSURE) where it will operate a bypass valve. Some of the bypass
valves are Manual in design while others utilize a switch an electric actuated valve.
You will need to make sure the switch closes below the pump’s DH pressure then
opens the valve. If it does not open the valve, check the switch to make sure it’s
setting pressure is appropriate, and that it electrifies the valve as it’s setting pressure
is reached. Refer to testing actuated valves for further assistance. Once the bypass
pressure is reached and the valve opens you will be required to press the white
“RESET” push button on the top of the switch to close the valve and return to
normal operation.
b. There are two possible sites for gauges on a Bag filter housing, make sure any
gauges that are installed are functional. If the gauge is ported into the housing above
the top of the filter bag, its pressure will rise as the bag blinds off. If the gauge is
ported into the housing below the top ring of the bag, its pressure will fall as the bag
blinds off.
Side Stream Bag Filters
c. Side Stream Bag Filters have one advantage over In-Line filters, no moving parts to
trouble shoot. If the bag becomes blinded off, then no flow will be pulled through
the bag and away from the filtration system. However it is very important that you
only open its flow regulation valve only so that 10-15% of the filtration’s flow is
pulled though the bag filter. To make sure this flow requirement is met, utilize an
ultrasonic flow meter, or only open the valve so that a 3 psi pressure drop from the
discharge pressure of the centrifugal separator is seen (pressure with valve open
versus pressure with valve closed). There are two possible sites for gauges on a Bag
filter housing, make sure any gauges that are installed are functional. If the gauge is
ported into the housing above the top of the filter bag, its pressure will rise as the
bag blinds off. If the gauge is ported into the housing below the top ring of the bag,
its pressure will fall as the bag blinds off.