When a cartridge reaches its water
holding capacity, its accordian pleats
swell shut and block the flow. This
"positive shutoff" prevents any
water-laden fuel from passing downstream
through the saturated cartridge. This
causes an increase in the differential
pressure which signals the operator to
change the cartridge.
Solid contaminants are removed by the
cartridge’s two particulate filter media
layers. The pleated accordian style design
provides a large surface area for maximum
dirt holding capacity. Models are offered
for particulate filtration down to either
5 or 1 micrometer size with 98% plus
efficiency. Performance is not affected by
the presence of surface active agents.
Differential Pressure Gauge
When the needle is in the green zone of
the gauge during normal flow, the
differential pressure is less than 15 psid
across the installed element, and the
element does not need to be changed out.
When the needle is in the red zone, the
differential pressure is more than 15 psid
and the element should be changed out. It
has reached its recommended maximum
pressure differential.