Van Air Systems FR-400 - Manual (Page 11)

PAGE 11
MAINTENANCE SECTION 9
9.1 DAILY INSPECTION
The following procedures should be performed daily:
• Check the dryer system operating conditions, ambient temperature
and inlet pressure.
• Monitor the dryer system for one complete cycle. Make sure it is
operating properly.
• Check the purge mufflers. Purge air should be exhausting from
one of the valves. If oil is present, the dryer and air system may be
contaminated with lubricants.
• Inspect separator/prefilter and prefilter drains for proper draining.
• Check the pressure differential indicator on prefilter and afterfilter.
If the differential pressure is unacceptable, replace the elements.
• Visually check the dryer system and piping for damage.
• Visually check the dryer system moisture indicator (blue dry or pink
wet)
9.2 SCHEDULED MAINTENANCE
12 MONTHS
• Fill lubricator with oil
• Replace purge muffler elements
• Replace the control air filter element
• Replace the separator/prefilter, prefilter, and afterfilter elements
• Clean the exterior of the pre-cooler
24-60 MONTHS
• The desiccant in the towers should be replaced every two to five
years. The life of the desiccant will vary depending on the inlet air
conditions. Systems with excessive contaminants and/or
inadequate filtration will decrease the life span of the desiccant
drastically. Once the desiccant is contaminated with lubricants, it
must be replaced.
• Periodically the pre-cooler core should be cleaned internally if the
process air contains excesive amounts of lubricating fluids.
9.3 DESICCANT REPLACEMENT
WARNING
DO NOT ATTEMPT TO REMOVE PLUGS UNTIL ALL AIR PRESSURE
IS OUT OF THE VESSEL. CHECK ALL TOWER PRESSURE
GAUGES, MAKING SURE THAT THEY ARE AT 0 PSIG AND
INCOMING PRESSURE HAS BEEN TURNED OFF.
ALWAYS WEAR EYE PROTECTION AND GLOVES WHEN
HANDLING THE DESICCANT. DESICCANT DUST MAY CAUSE
EYE AND SKIN IRRITATION. AVOID BREATHING THE DUST AND
PROLONGED CONTACT WITH THE SKIN.
FIRST AID IN CASE OF EYE CONTACT, IMMEDIATELY FLUSH
EYES WITH PLENTY OF WATER FOR AT LEAST 15 MINUTES.
CONSULT A PHYSICIAN.
Take dryer system off stream following the SHUTDOWN PROCEDURES
IN SECTION 7.
Remove the plugs from the desiccant drain and fill ports; drain old
desiccant from each tower.
Remove any oil, dirt, or scale from the towers and inlet piping. Do
NOT weld, grind or sandblast the vessels as this voids the ASME
Certification. The vessels may be steam cleaned internally and
externally to remove dirt and oil.
CAUTION
Make sure that the towers are clean to prevent contamination of
new desiccant.
Replace plugs securely on desiccant drain ports. Apply pipe thread
sealant as necessary.
9.5 CLEANING THE EXTERIOR OF THE PRE-COOLER
The pre-cooler core should be cleaned regularly. Accumulation of dirt
or other contaminants shch as oils will greatly reduce the efficiency of
the pre-cooler.
Normal accumulation of dirt can be removed by using compressed air
to blow off the core. If the core becomes contaminated with oil-laden
particles, it will need to be steam cleaned. Use extreme care when
cleaning the core as the aluminum fins can be easily damaged.
Make sure that the desiccant drain plugs are installed before
attempting to fill the towers. Load desiccant through the desiccant
fill ports. REFER TO SECTION 3.1 FOR PROPER DESICCANT
AMOUNTS.
Reinstall the fill plugs. Apply pipe thread sealant as necessary.
Follow START UP PROCEDURES IN SECTION 5.1 to start up and place
dryer in operation.
9.4 CONTROL AIR FILTER ELEMENT REPLACEMENT
Shutdown the dryer per Shut-Down Procedures SECTION 7.
Turn manual valve (petcock) on bottom of control air filter to ensure
that the dryer is completely depressurized.
WARNING
DO NOT REMOVE THE FILTER BOWL FROM HEAD UNTIL
HOUSING IS COMPLETELY DEPRESSURIZED.
After all pressure is out of the dryer, grasp the filter bowl firmly and
push upward while turning it counter-colckwise (as viewed from the
bottom) to remove it from the filter head. If prefered strap wrenches
can be used to remove bowl. Make sure that the bowl does not drop.
Remove the used element from element adaptor in filter head by
pulling down. Discard used element properly.
Remove new element from the shipping package. Check to make sure
that the o-ring is properly positioned in endcap and has been lightly
greased.
Grasp clean element by bottom endcap and push element onto
element adpater firmly, but do not force beyond normal stop.
Check o-ring in filter head. Replace if worn or damaged.
Clean and lubricate threads on bowl with light grease. This will
facilitate removal of bowl at next servicing.
Carefully raise filter bowl over element and screw into head, then
tighten. DO NOT OVERTIGHTEN.
Close manual drain valve (petcock).
Following the start up procedures in SECTION 5.1 for the dryer, place
the dryer on stream.