INTRODUCTION
HRD Series and HRD-EM (Energy Management) Se-
ries heatless desiccant compressed air dryers remove
moisture from compressed air to achieve a standard
pressure dew point of –40°F. Refer to Table 5 for rated
capacity and other dryer specifications. The heatless
dryer supplies a continuous flow of dry compressed air
by alternately cycling the airflow through two desic-
cant beds; one adsorbs moisture from the inlet air
while the other is regenerated by a portion of the dry
air from the active bed.
To ensure continuing good dryer performance and safe
operation, everyone who installs, uses or maintains the
dryer must read and carefully follow the instructions in
this manual. Throughout the manual, the word dryer is
used to refer to HRD and HRD-EM Series heatless air
dryers.
SAFETY
HRD and HRD-EM Series dryers are designed and
built with safety as a prime consideration; industry-
accepted safety factors have been used in the design.
Each dryer is checked at the factory for safety and op-
eration. The desiccant vessels are hydrostatically
tested to 1½ times the maximum pressure in accor-
dance with ASME code requirements. A factory-
installed safety relief valve is standard on each dryer.
WARNING
The following safety rules must be observed to
ensure safe dryer operation. Failure to follow
these rules may void the warranty or result in
dryer damage or personal injury.
1. Never install or try to repair any dryer that has
been damaged in shipment. See the Receiving and
Inspection instructions in this manual for appro-
priate action.
2. Never operate the dryer at pressures or tempera-
tures above the maximum conditions shown on
the data plate.
3. Always supply electrical power that complies
with the voltage shown on the data plate.
4. Never dismantle or work on any component of the
dryer or compressed air system under pressure.
Vent internal air pressure to the atmosphere be-
fore servicing.
5. Never perform electrical service on the dryer un-
less the main power supply has been discon-
nected. Parts of the control circuit may remain
energized when the power switch is turned off.
HRD and HRD-EM Series (Bulletin 378)
6. Use only genuine replacement parts from the
manufacturer. The manufacturer bears no respon-
sibility for hazards caused by the use of unauthor-
ized parts.
Safety instructions in this manual are boldfaced for
emphasis. The signal words DANGER, WARNING
and CAUTION are used to indicate hazard serious-
ness levels as follows:
DANGER—Immediate hazard which will result in se-
vere injury or death.
WARNING—Hazard or unsafe practice which could
result in severe injury or death.
CAUTION—Hazard or unsafe practice which could
result in minor injury or in product or property dam-
age.
The dryer data plate, attached to the electrical control
box, contains critical safety and identification informa-
tion. If the data plate is missing or defaced, immediate-
ly contact your local distributor for a replacement.
INSTALLATION
Receiving and Inspection
Immediately upon receipt of the dryer, thoroughly in-
spect for damage that may have occurred during ship-
ping. Since the dryer is shipped F.O.B. New Castle,
Delaware, the carrier is legally responsible for damage
incurred during shipping. Shipping damage is not cov-
ered by the dryer warranty.
If goods are received short or damaged, notify the car-
rier and insist on a notation of the loss on the face of
the bill of lading. Otherwise no claim can be enforced
against the carrier.
If concealed loss or damage is discovered, notify the
carrier at once and request an inspection. The carrier
will make an inspection and grant a concealed damage
notation. The carrier will not consider any claim for
loss or damage unless an inspection has been made. If
you give the carrier a clear receipt for goods that have
been damaged or lost in transit, you do so at your own
risk and expense.
If there is any damage, file a claim with the carrier,
then call your local distributor for further instructions.
Handling
The dryer is designed to be moved by means of the
shipping skid or the base channels. Handle the dryer
with care and only with equipment capable of lifting
the load.
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