8.1 - POOR DEWPOINT
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VISUAL
INDICATION
Low reading on
hygrometer
Moisture downstream
Low dewpoint
POSSIBLE CAUSE
Faulty sensor
No flow rate across
sensor
Insuficient purge air
Entrained water
Low inlet pressure
High inlet temperature
Overflow of dryer
Failure to switch, all
gauges showing line
pressure
High pressure drop
across dust filter
CHECK
Check by using other
sensor
Flow at exhaust from
sensor block
Check using rotometer
Check all drains
Gauges and dryer
sizing
Using temperature
gauge
Flow rate through
dryer and dryer sizing.
Cam timer rotation.
Desiccant attrition.
REMEDY
Change sensor
Adjust flow restrictor to
within spec.
Adjust if necessary
Repair if necessary
Resize compressor or
reduce air demand
Check compressor after
cooler
Adjust compressor
output, resize, Fit 100%
flow control devices
(FCD)
Check electric cam
motor is turning, Check
electric supply
Check fuses (pneumatic)
Change desiccant.