AIRTAK SD-10 through SD-250 User manual

REFRIGERATED AIR DRYERS
Operating Instructions
Models SD-10 through SD-250
AIR/TAK
107 W. Main Street
Worthington, PA 16262
724.297.3416
www.airtak.com
11/2013

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SPECIFICATIONS:
Refrigerant:
R134a
Maximum Inlet Pressure:
250 psig
Maximum Inlet Temperature:
120°F
Minimum Ambient Temperature:
50°F
Maximum Ambient Temperature
110°F
OPERATION:
Under normal conditions, the air dryer will run continuously when power is on. The
dryer will provide a specified pressure dew point for the compressed air system with
little maintenance or adjustments required.
Moisture and condensation will be removed from the moisture separator automatically
through the automatic drain.
Units are designed for inlet air temperature of 100°F. If the inlet air temperature
exceeds 100°F, there is a possibility of overloading the refrigerant compressor.
The allowable range for ambient temperature is 50°F to 110°F. At ambient temperature
above 100°F, refrigeration capacity will decrease with a corresponding increase in
pressure dew point. If the thermal overload switch trips out and stops the compressor,
the unit will not restart until it has cooled.
INSTALLATION:
General:
A. Only qualified service people should install a compressed air dryer. Compressed
air, machinery and electricity are involved in installation; all can be dangerous if not
handled properly.
B. Upon unpacking your dryer, examine it for any external damage. If such damage
exists, report it to the delivering carrier immediately and file a freight claim with the
responsible carrier.
C. Prior to attempting installation of the dryer read the accompanying literature
thoroughly. Failure to follow the enclosed recommendations may result in invalidation
of the warranty.
D. Dryers are designed for installation and operation in typical indoor industrial
atmospheres. Do not install or operate dryers in hazardous locations or in explosive or
flammable atmospheres.

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Ambient Conditions:
A. Indoor installation is recommended. Dryers installed outdoors must be well
protected from precipitation, dust, dirt, debris and animals.
B. The unit should be installed in a well ventilated area. Ambient temperature must be
in the temperature range of 50°F to 110°F.
C. If the dryer must be installed in area containing airborne particles or fines, or in an
oily atmosphere conducive to the collection of dust and dirt particles on the surface of
and in-between the fins of the refrigerant condenser, install and maintain an ambient air
filter.
D. Position the dryer to allow free circulation of cooling air through the front and sides
of the dryer.
Mounting:
A. The dryer should be placed on a rigid, level surface.
B. If mounted on a shelf or on any surface or structure above the floor level, the dryer
should be bolted down using the mounting holes provided in the cabinet base. Not all
models have mounting holes.
C. The dryer should be isolated from excessive vibration, which could be transmitted
through the mounting surface or attachment piping.
Electrical:
A. For units 10 scfm through 100 scfm, the unit should be connected to an
appropriate grounded receptacle based upon its nominal voltage. Be sure the power
cord is protected from possible damage after installation. For units 150 scfm to 250
scfm, you may need a qualified electrician to aid in the connection with its terminal
block based upon its nominal voltage.
B. The dryer should be connected to a fused disconnect, having a fuse size not to
exceed the maximum fuse size indicated on the dryer data label.
C. Power supplied to the dryer must conform to the electrical specifications listed on
the dryer.
D. On models 150 scfm to 250 scfm, they have a junction box with a 1/2 inch knockout.
A conduit connector is provided. To connect to the terminals in the junction box,
remove the aluminum access plate. The access plate is held in place with two screws.
Thread the power cord through the conduit connector and, using the appropriate
electrical schematics in this literature, connect to the terminals in the junction box.
Replace the access plate.
Dryer installation should follow the installation arrangements shown in Figure 1. An
aftercooler and moisture separator with automatic drain are recommended to reduce the

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moisture removal and temperature variation demands on the refrigerated dryer.
Between the compressed air receiver and dryer, a general purpose coalescing filter with
an automatic drain is used to remove liquid water, liquid oil and solid particles from the
airstream. Pre-filtering eases the load on the dryer and prevents an emulsion of water,
oil and particulates from forming. This emulsion can leave a deposit that reduces heat
exchanger efficiency and clogs automatic drains.
For applications that require ultra-clean air, additional filtering may be required to
remove the oil aerosols and vapors present in most systems. Oil coalescing filters
remove oil in aerosol form. To remove oil vapor from the air stream use a filter fitted
with an adsorbing activated carbon cartridge at the dryer outlet.
Note that the inlet and outlet ports of the air dryer are labeled. A dryer bypass valve
should be installed for air dryer servicing. If the aftercooler exit air temperature
averages less than 100°F, the dryer including prefilter and bypass system can be
placed between the aftercooler separator and receiver.
If not already in place, connect condensate drain tube to the dryer’s moisture separator
drain trap. Position outlet of drain tube in such a manner that condensate will be
drained away from dryer and other mechanical or electric equipment.
Make sure when piping is in place that no undue stress is placed on dryer connections.
Union joints or flexible connections are recommended to relieve stress.
Dryer is to be connected to an appropriate electrical power source based upon
specifications shown on unit data label. Do not connect unit to a power source other
than that called out on data label. Power source should incorporate a fused disconnect
using a fuse, not exceeding the maximum fuse size stated on the dryer data label.
Piping:
A. Piping installation should follow general air line piping procedures.
B. A bypass valve system is recommended in the dryer’s pipe connections. This
permits servicing of the dryer without the interruption of the airflow.
C. If the pipes connecting the dryer vibrate, such as from compressor vibration, use
vibration absorbers so that the dryer is not damaged over time by the vibration.
D. The inlet and outlet ports on the dryer are labeled.
E. Direct the drain tube under the dryer to a suitable sump. Do not restrict the drain.
Filtration:
A. A compressed air filter with automatic drain should be installed upstream of the
dryer. Filtration of dirt, rust and liquids from the supply air will greatly enhance the
performance and life of the dryer. Your distributor can provide additional information on
compressed air filters.

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AIR & REFRIGERANT CIRCUITS:
Air Circuit
Warm wet compressed air enters the refrigerant dryer at the inlet port. (On models 30
scfm through 250 scfm) It first passes through an air-to-air heat exchanger where its
temperature is lowered by the cool air exiting the dryer. It then enters the evaporator or
refrigerant-to-air heat exchanger where its temperature is lowered. The condensate
(water) generated by the cooling action is collected in the moisture separator and
automatically removed. The dry air then leaves the separator, and enters the air to air
heat exchanger (30 scfm through 250 scfm models only) where it is heated and the air
exits through outlet port.
Refrigerant Circuit
The refrigerant compressor compresses refrigerant vapor to a high pressure and
temperature. The compressed vapor then flows through the condenser where it is
cooled and forms a liquid. After this, it is filtered through the refrigerant filter-dryer
where any traces of moisture and contaminants are removed. The expansion valve
lowers the pressure which in turn lowers the temperature of the liquid refrigerant to its
preset level. It remains at this pressure and vaporizes as it flows through the
evaporator/refrigerant-to-air heat exchanger absorbing heat from the air being dried.
The refrigerant then flows back to the compressor and the cycle repeats.
The dryer uses R134a refrigerant. For units with a refrigerant suction pressure gauge,
the refrigerant suction pressure is listed in chart below for the appropriate model. If a
lower pressure dew point is required, back off the adjustment screw on the expansion
valve until gauge pressure reaches the desired level.
Model Number
Gauge Pressure Reading
SD10 through SD20
33 to 38 psig
SD30 through SD40
29 to 33 psig
SD50 through SD100
30 to 34 psig
SD150 through SD250
31 to 35 psig

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TROUBLESHOOTING GUIDE
PROBLEM
POSSIBLE CAUSE
REPAIR
Water in
system.
1. Inlet and outlet connections are
reversed.
Check inlet and outlet connections. This
dryer is designed for air flow in one
direction only. Inlet and outlets are
identified.
2. Drain trap is clogged or inoperative.
Restore a free flow of water. Trap is a
float type. The bowl will normally contain
some water and valves should be free
and clean. Trap should be periodically
checked and cleaned. After initial
installation, the trap should be checked
weekly for dirt, pipe scale, etc. for the 60
days.
3. Bypass system is open
Check the valves. Bypass piping should
be installed around the dryer so the dryer
may be isolated for service without
shutting down the air supply. During
dryer operation valves must be set so all
air goes through the dryer.
4. Free moisture remains in pipe lines
Blow out the system. Before dryer is first
started all few moisture should be blown
out of the system.
5. Excessive air flow
Check actual (scfm) flow through the
dryer. This dryer is designed for a
specified air flow. If air flow into the dryer
exceeds specifications, water removal
capacity may not be sufficient, resulting
in liquid carry-over downstream. Check
the flow of air system.
6. Excessive free moisture
Check the separator and drip legs ahead
of the dryer. If this dryer is installed at an
individual work station or in one portion
only of the piping system, instead of near
the compressor, there may be an
accumulation of free moisture in the
pipeline ahead of the dryer. If the
moisture is pumped into the dryer
intermittently, water removal capacity
may not be sufficient. A separator or air
line filter with an automatic trap should
be installed ahead of the dryer.
7. High temperature inlet air
Rated operating temperature is 100°F.
The dryer is designed for inlet air
temperature of 100°F. Temperatures
above 100°F may cause water down
stream and an overloading of the
condensing unit. Increase dryer size or
install an aftercooler.
8. Clogged condenser fins
Clear fins of all obstructions. Clogged
fins in the condenser coil will re4strict air
passage and reduce refrigeration
capacity, causing water down stream.
Fins should be periodically checked and
cleaned. Install ambient air filter.

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TROUBLESHOOTING GUIDE continued
9. Shortage of refrigerant
Fix the leak and add a charge of
refrigerant. Loss of refrigerant will cause
improper functioning. A qualified
refrigerant specialist should perform the
necessary repairs, or factory should be
contacted if the unit is under warranty.
10. Refrigeration system is not functioning.
Check to be certain refrigerant
compressor is running. It is possible for
the fan to be operating but not the
compressor. Compressor not running
can be caused by several factors. A
qualified refrigeration contractor should
check refrigerant and electrical controls.
11. Excessive pressure dew point.
Readjust expansion valve. The
expansion valve operates like a pressure
regulator. Loosen lock nut. Turning the
adjustment screw on the expansion valve
counterclockwise decreases refrigerant
pressure and lowers refrigerant
temperature. Adjust valve in ¼ turn
increments to allow 15 minutes for
pressure stabilization with air flowing.
Caution: too low a setting can cause
moisture in heat exchanger to freeze.
High
Pressure
Drop
1. Excessive air flow
Check the air flow. This dryer is
designed for a specified air flow as
indicated. If air flow into the dryer
exceeds specifications, the water
removal capacity may be insufficient
resulting in a liquid carry-over
downstream. Check the flow of the air
system.
2. Freeze up
Readjust refrigeration controls. Frosting
of the lines is an indication the controls
are set too low. MODELS 10 SCFM
THROUGH 40 SCFM -Controls may be
adjusted in the field by means of the
expansion valve adjustment screw.
MODELS 50 SCFM THROUGH 250
SCFM Controls may be adjusted in the
field by means of the hot gas bypass
valve. Loosen lock nut. Turn screw
clockwise to increase refrigerant
pressure setting which will increase
refrigerant temperature. Turn screw in ¼
turn increments until frost disappears.
Allow 15 minutes between adjustments
for pressure stabilization with air flowing.
The unit will
not run or
cycles off
and on.
1. Line disconnect switch is open. Power
on light will be off.
Close the start or disconnect switch. If
the dryer is not operating check the
disconnect switch or circuit breaker to be
certain it is on.
2. Fuse or breaker is open. Power on light
will be off.
Replace fuse or reset the breaker. The
fuse to the power line should be
checked. Make sure the correct size
fuse is used. See data tag label for
correct fuse size.

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TROUBLESHOOTING GUIDE continued
3. Faulty refrigerant compressor or
controls. Power on light will be on.
Determine the cause and make
corrections. Failure of compressor to run
may be due to several factors. A
qualified refrigeration specialist should
check all electrical and refrigerant
controls, or factory should be contacted if
unit is in warranty.
4. High Temperature inlet air. Power on
light will be on
The dryer is designed for inlet air of
100°F. Temperatures above 100°F, may
cause poor performance and an
overloading of the condensing units.
5. High ambient temperature. Power on
light will be on.
Check the ventilation. Ambient
temperature should not exceed 110°F.
Air circulation around the dryer should be
adequate, and proper ventilation in the
equipment room should guarantee a
correct ambient temperature.
6. Clogged condenser fins. Power on light
will be on.
Clear fins of all obstructions. The
clogged fins in the condenser coil will
restrict air passage and reduce
refrigeration capacity, causing unit to
shut down due to overheating. Fins
should be periodically checked and
cleaned. Install ambient air filter.
7. Shortage of refrigerant.
Fix the leak and add a charge of
refrigerant. Loss of refrigerant will cause
improper functioning. A qualified
refrigerant specialist should perform the
necessary repairs, or factory should be
contacted if the unit is in warranty/
“Hi-Temp”
Indicator light
is on
1. Excessive air flow, high temperature inlet
air, clogged condenser fins or high ambient
temperature
See solution in this troubleshooting guide
for the appropriate possible cause. “Hi-
Temp” Indicator Light is activated when a
sensor (thermal/current overload)
experiences excessive current draw to
the compressor or the temperature of the
compressor shell to which it is attached
becomes excessive. Energization of the
light indicates power to the compressor
has been disrupted for one of the above
reasons. This may be caused by
excessive ambient or inlet air
temperature but it is not directly
indicative of either condition.

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AIR/TAK WARRANTY POLICY
AIR/TAK products will be warranted to be free from defects in materials and workmanship for a period of one
year from date of shipment or up to one year from the verified date of installation not to exceed 15 months.
Date of installation will be verified upon receipt of the completed Warranty Registration Card. All AIR/TAK
refrigerated dryers will additionally be warranted on parts only (excluding fan motors and drain valves) for a
period of two years from the date of shipment. Deliquescent and regenerative air dryer pressure vessels and
refrigerated air dryer heat exchangers have a 5-year prorated warranty.
All damaged pressure vessels and heat exchangers returned to AIR/TAK for warranty consideration must be
returned freight prepaid. Warranty will be determined after factory inspection. Failure to return a damaged
heat exchanger or pressure vessel will result in warranty denial.
Repairs, adjustments, parts, etc. are limited to actual labor cost provided that such defects are promptly
reported and approved following AIR/TAK's warranty procedures. In no event shall the cost of repairs exceed
the actual cost of materials and labor.
AIR/TAK or its representatives reserve the right to decide which warranty items are authorized. AIR/TAK shall
not be liable for incidental or consequential damages which may result from a breach of the warranty
described above.
For more information on warranty policies and procedures, contact your authorized AIR/TAK Distributor.
AIR/TAK's line of quality compressed air system products includes:
COMPRESSED AIR SYSTEM FILTERS
REFRIGERATED AIR DRYERS
EXTERNALLY HEATED REGENERATIVE AIR DRYERS
HEATLESS REGENERATIVE AIR DRYERS
BLOWER PURGE REGENERATIVE AIR DRYERS
DELIQUESCENT AIR DRYERS
NATURAL GAS DRYERS
NATURAL GAS PRODUCTION SKIDS
NATURAL GAS FILTERS
MIST ELIMINATORS
NITROGEN GENERATORS
FLUID CHILLERS AIR-COOLED AFTERCOOLERS
For an authorized distributor near you, contact AIR/TAK at:
AIR/TAK Inc.
107 W. Main Street
Worthington, PA 16262
724.297.3416
FAX [phone]
www.airtak.com