6
Compressor
Aftercooler
Receiver
Separator
Desiccant
Dryer
FIGURE 2A
(B & C) PREFILTERS - Adequate filtration is required upstream of the
dryer in order to protect the desiccant bed from contamination. The
following filtration are recommended:
B - Particulate/Gross Liquid Removal - On heavily contaminated systems
use a gross contaminant filter to remove solids and high inlet liquid
concentrations.
C - Oil Aerosol Removal - On systems with lubricated compressors, use
an oil removal filter to remove oil aerosols and protect desiccant bed from
oil contamination.
(D) DESICCANT DRYER
(E) AFTERFILTER - To ensure downstream air purity (prevent desiccant
dust from traveling downstream) adequate filtration downstream of the
dryer is required. Typically 1 micron filtration is specified although finer
filtration is available.
OR
Oil Vapor Adsorber - Use as an afterfilter to remove oil vapor and its
subsequent taste and odor and to protect down-stream components from
solid particles 0.01 micron and larger.
NOTE
By-pass lines and isolation valves are recommended so that maintenance
work can be performed without shutting off the air supply.
2.1 Location in the compressed air system.
NOTE
Air Compressor should be adequately sized to handle air system demands
as well as purge loss. Failure to take this into account could result in
overloading air compressors and/or insufficient air supply downstream.
NOTE
It is desirable to install dryer where compressed air is at the lowest
possible temperature (downstream of aftercoolers) and the highest
possible pressure (upstream of pressure reducing valves) without
exceeding the maximum working pressure.
(Refer to Figure 2A)
(A) AFTERCOOLER/SEPARATOR - Compressed air entering dryer must be
cooled to at least 120
°
F (49
°
C). Use aftercooler and separator if higher
temperatures are present.
NOTE
Installation of a refrigerated dryer ahead of a pressure-swing desiccant
dryer does not increase desiccant dryer capacity or reduce purge flow
requirements. However a cooling unit installed ahead of the desiccant
dryer reduces the inlet air temperature and outlet air dew point.
2.0 INSTALLATION
2.2 Minimum & Maximum Operating Conditions
The compressed air supply inlet should be checked periodically to ensure
that equipment design specifications are not exceeded. Normally the
compressor installation includes intercoolers, aftercoolers, separators,
receivers, or similar equipment which adequately pretreat the compressed
air supply in order to avoid excessively high air temperatures and liquid
slugging of downstream equipment.
2.2.1 Compressed air conditions
2.2.1.1 Maximum working pressure:
Refer to dryer Serial Number Tag.
WARNING
Do not operate the dryer at pressures above the maximum
pressure shown on the tag.
2.2.1.2 Minimum working pressures:
150 psig (10.5 kgf/cm
2
) MWP models -
60 psig (4.2 kgf/cm
2
) for dryers operated on a 10 minute cycle
80 psig (5.6 kgf/cm
2
) for dryers operated on a 4 minute cycle
250 psig (17.6 kgf/cm
2
)MWP models -
125 psig (8.8 kgf/cm
2
) for dryers operated on a 10 minute cycle
150 psig (10.5 kgf/cm
2
) for dryers operated on a 4 minute cycle.
If lower inlet pressures are encountered, consult factory.
2.2.1.3 Maximum inlet compressed air temperature:
120
°
F (49
°
C)
NOTE
If inlet air is higher than 120
°
F (49
°
C) the air must be precooled
with an aftercooler.
2.2.2 Ambient temperatures:
Minimum:
Standard units: 35
°
F (1.7
°
C)
Units with optional low ambient package: - 10
°
F (-23
°
C)
Maximum: 120
°
F (49
°
C)
NOTE
If dryer is installed in ambients below 35
°
F (1.7
°
C) heat tracing of
the prefilters and inlet piping and valves is necessary to prevent
condensate from freezing. If installing heat tracing, observe electrical
class code requirements for type of duty specified.
2.3 Mounting
Install dryer on a level pad on floor. Holes are provided in the
floor stand base angles for floor anchors if desired.
NOTE
Floor anchors must be used if area is subject to vibrations.
2.4 Piping
2.4.1 Inlet and Outlet connections
Observe location of inlet and outlet connections as indicated in
Figure 2B, 2C, or 2D and connect inlet and outlet piping.
NOTE
All piping must be supported so as not to bear on the dryers or
filters.
2.4.2 Isolation valves
If isolation valves are installed, it is recommended that gate
valves be used to ensure that dryer is pressurized slowly. This is
particularly true if isolation valves are placed before and after pre-
and afterfilters where rapid pressurization could cause excessive
pressure drop across filter cartridges.
Prefilter(s)
Afterfilter