Arrow Pneumatics RH203, Instruction & Maintenance Manual

Page: 5 / 23

5
3. Generally, locate your dryer downstream from the air receiver. The only exception would
be on applications with a fluctuating demand. Then the dryer should be located
upstream of the receiver to avoid air surges through the dryer’s desiccant beds.
4. Provide adequate space around the dryer for servicing. Bolt dryer skid to foundation,
where possible.
C. SUGGESTED PIPING ARRANGEMENT
Wet air inlet is at the dryer’s bottom piping assembly. Dry outlet air is from the dryer’s top
piping assembly (see attached flow diagram).
In situations where air supply is required 24 hours a day (it is undesirable to interrupt the
airflow), a three valve bypass system is recommended to bypass the dryer. Use the fewest
elbows and taper connections necessary to keep pressure drop at a minimum.
D. PREFILTERS / AFTERFILTERS
It is important that a prefilter and an afterfilter be provided in your dryer installation.
Prefilters, located before dryer, protect desiccant beds from contamination by oil, entrained
water, pipe scale, etc., thereby extending dryer desiccant life. Locate prefilters as close to
dryer as possible.
It is recommended that a mechanical separator be installed immediately preceding the
prefilter to remove the bulk liquid oil and entrained water.
CAUTION
LIQUID WATER SHOULD BE REMOVED BEFORE THE AIR ENTERS THE
DRYER. BE SURE SEPARATORS, PREFILTERS AND DRAINS ARE IN GOOD
WORKING ORDER.
After filters, located after the dryer, help eliminate the possibility of desiccant dusting and
carryover into the air system.