Domnick Hunter PNEUDRI DH Series, Installation, Operating, & Maintenance Instructions

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G) Fault Finding
PROBLEM VISUAL INDICATION PROBABLE CHECK REMEDY
CAUSE
Poor All pressure gauges Loss of power. Incoming supply. Replace fuses if
Dewpoint. showing line pressure necessary.
for more than 5 mins.
Heater failure. Check heaters for Replace if
electrical integrity. necessary.
Poor signal to open Remove non- Replace seals or
exhaust valve. pressurised side cylinders.
tube. Check fittings
for air leaks.
Exhaust valve As above. As above.
by-passing.
Faulty logics. Check function by Change if
removing tubes. necessary.
Air leak from Broken diaphragm Replace solenoid
solenoid. in solenoid valve. valve.
Pressure gauge Exhaust elements Element media Replace elements.
showing back blocking up. blocked up with Check for
pressure on water, desiccant or desiccant attrition
depressurised side. oil carryover. and oil carryover.
Faulty ‘or’ logic Remove non- Replace ‘or’ logic.
at moisture pressurised side
indicator causing tube, and check
by-passing. for back pressure.
Dryer fails to Air leak. Broken or damaged Check and renew
pressurise. exhaust/inlet valve where necessary.
discs.
Dryer pressurised Check cam timer Replace where
on one side only. rotation and fuse. necessary.
Moisture content Entrained water. Check pre-filter Replace drain
indicator (amber). drains if necessary.
Purge air too low. Check purge rate. Reset purge rate.
Inlet pressure Check inlet Increase inlet pressure
too low. pressure.
Air flow demand Check for recent Ensure flow rate does not
too high. additions to exceed the rated flow
compressed air capacity of the dryer.
system or
excessive peak
demands.