Parker Airtek TW 10 Instruction manual

HEATLESS DESICCANT
COMPRESSED AIR DRYER
MODEL’S 75 - 6000
S/N
INSTALLATION, OPERATION
& MAINTENANCE MANUAL
Service Department
1-800-451-6023

Dear Customer,
Let us take this opportunity to introduce our company.
AIRTEK is an innovative manufacturer of industrial equipment for compressed
air systems.
Our product line includes natural gas dryers, fluid coolers, water separators, air
filters, refrigerated air dryers, and heatless and heat reactivated desiccant air
dryers. Our products can be found in all corners of the world.
No effort has been spared to provide a comprehensive instruction manual for
the use of the AIRTEK Dryer. Information is given not only for the user, but
also for the technical personnel who may repair the dryer in the event that this
is ever necessary. It is recommended that all who will have responsibility for
the dryer carefully read all sections of this manual before commencing with
the installation.
The most important step is for you as a customer is to call us first at
1-800-451-6023 if you are experiencing a problem with your dryer.
If there is a question regarding this manual or our warranty policies and
procedures, please call. We would be happy to speak with you.
Thank you for choosing AIRTEK products.
AIRTEK Service Department

Section 1 Inspection & Installation
Section 2 Safety & System Precautions
Section 3 General Operation
Section 4 Sequence of Operation
Section5 StartUp
Section 6 Operational Notes
Section 7 Shutdown Procedures
Section8 DemandCycles
Section 9 Maintenance Program
Section10 Parts
Section 11 Trouble Shooting Guide
Section 12 Wiring Diagrams
Section 13 High Humidity
Section 14 Timing Charts
Section 15 Analyzing Chart
Section 16 PowerLoc System
Section 17 JC, JT & JL Filters
Section18 Warranty

SECTION 1 Installation and Inspection
PRIOR TO INSTALLATION OR START-UP OF DRYER, THIS ENTIRE MANUAL SHOULD BE READ AND
UNDERSTOOD.
INSPECTION
All Dryers are tested and inspected at the factory prior to shipping. Inspect the dryer carefully upon arrival
and note any damage on the freight bill. Uncrate and inspect for concealed damage. File claims with the
carrier immediately and notify the AIRTEK service department.
Dryer Location
Locate the dryer in an area accessible for maintenance. The dryer should have minimum 36" clearance on
all sides. See dimensional print for specific clearance requirements. The area should be clean, well lighted
and have a level, vibration free floor. For standard applications, ambient temperatures should range
between 35°F and 100°F. Consult the factory concerning applications outside this temperature range.
Installation
(See typical installation drawing)
NOTE: All piping and electrical connections should be checked to insure they have maintained their
integrity during shipping and installation.
WARNING! Incorrect installation may void warranty! IMPORTANT! Sizes 1500 SCFM and up require
field desiccant charging. Units 1500 and up are shipped empty due to weight constraints.
- Coalescing Pre-Filter with auto drain must be installed.
- Dryers are designed for 100°F inlet temperature or less.
- Ambient temperatures should be between 35°F and 100ºF.
- Dryer should be located in an area accessible for maintenance.
- Location should be clean, cool, with a level, vibration free floor.
- Location of receiver may vary depending on particular conditions and type of compressor.
- Auto drains are required when receiver is mounted up- stream of dryer.
Make the following connections:
1. Inlet piping, including an isolation valve.
2. Outlet piping, including an isolation valve.
3. Coalescing Pre-Filter and Particulate Afterfilter.
IMPORTANT! Desiccant dryers are designed to remove water VAPOR only!
Locate the coalescing filter as close to the dryer as possible. The air to be dried must pass through a
Coalescing Pre-Filter for removal of entrained condensate and oil to prevent fouling of the desiccant.
Liquid condensate entering the bed will lead to overloading of the dryer, poor dew point performance,
and rapid deterioration of the desiccant. Oil entering the desiccant bed may permanently reduce the
capacity of the desiccant.
A Particulate Afterfilter should be provided to prevent desiccant dust from traveling down stream.
Desiccant dust may cause contamination and excessive wear to equipment. Differential pressure
indicators should be installed on filters for monitoring of elements. A particulate filter before the
dryer and adsorber after the dryer are optional.
4. Auto Drain on Pre-Filter. An Automatic Drain is required on the Pre-Filter and all other upstream
collection points to remove condensate.

5. IMPORTANT! Bypass piping is necessary. A bubble tight valve should be used for bypass
around filters and dryer for servicing.
6. Make required electrical connections to control box. Refer to applicable drawings.
NOTE: Customer to provide short circuit protection for dryer.
7. Access ports should be provided upstream and down- stream of the dryer for dew point, pressure,
and temperature checks. Periodic checking of the dew point just downstream of the dryer is the best
indication of whether the dryer is performing as expected. A High Humidity Alarm or Powerloc are
available as options.
8. All piping should be adequately supported and at least of equal size to the dryer connections.
9. To reduce maintenance and increase dryer efficiency, the exhaust ports can be piped to a location
where the exhaust mufflers are not required. The piping MUST NOT create any back pressure on the
regenerating tower and must be up-sized accordingly. It is recommended that the exhausts be piped
separately for ease of troubleshooting and maintenance.
Before any attempt is made to operate the AIRTEK dryer, the operator should thoroughly read and
understand this instruction manual. Improper operation will cause poor results from the dryer.
Recommended Installation

SECTION 2 Safety and System Precautions
- Use EXTREME CAUTION when working in the vicinity of the dryer.
- Relieve pressure before servicing dryer or associated equipment.
- Disconnect power before servicing dryer.
- Use ear and eye protection when in the vicinity of the dryer or exhaust ports, especially if the dryer is
being operated without mufflers. Even when mufflers are used, a tower blowing down to atmosphere will
raise particles, create more noise than during “normal” operation and may startle an individual not used
to this portion of the operation.
- In the case of an overpressure situation there is a safety relief valve on each tower designed to protect
the equipment. If these end up pointed in a hazardous direction after dryer installation, they should be
piped to safe location.
- Automatic or manual drain valves will eject water, oil, particulates and air under partial pressure when
operated. Proper precautions must be taken.
-Condensate drainage from compressed air systems maycontain oil or other contaminants. Follow all
applicable regulations for safe handling and disposal.
- Various component failures could cause large air loss and subsequent pressure drop. Preventive
maintenance should be performed to reduce the likelihood of this. If this occurs, bypass the dryer
immediately to restore flow and pressure.
- Activated Alumina dust is considered a nuisance dust. Proper precautions should be taken when
handling desiccant. For more information and for other types of desiccant, refer to applicable Material
Safety Data Sheet. For disposal of used desiccant refer to the applicable regulations.
NOTE: Desiccant contaminated with oil or other foreign substances may be covered under disposal
regulations for the contaminant.
SECTION 3 General Operation
Desiccant dryers work on the principle of adsorption. Adsorption is the process of removing water VAPOR
from the air to be dried. All condensed liquid water should be removed from the inlet air stream prior to
reaching the dryer by suitable separators, traps, filters, and drains. The dryer can not be burdened with
liquid condensate carry-over.
All desiccants are adversely affected by oil, aerosols, dirt, rust, scale or liquid water. Effective pre-
filtration in conjunction with automatic condensate drainage is a must for proper dew point
suppression and long desiccant life.
The saturated inlet air is alternately cycled through each of the two desiccant beds. One bed is “on-line”
at full line pressure and flow, adsorbing water vapor from the saturated inlet air. This is the drying bed.
The other bed is “off-line” at atmospheric pressure (0 PSIG) being regenerated by a depressurized
portion of the dried outlet air (purge air). This is the regenerating bed.
The quantity of purge air for a standard pressure dryer is approximately 15% of inlet design flow. This air
is taken from the dry air outlet, directed through the purge flow controls, purge check valves, desiccant
bed, and finally exhausted to atmosphere to accomplish regeneration. Purge air consumption is typically
the largest cost involved with operating a heatless desiccant air dryer. (Purge air is “non-recoverable” and
the air system in question must be designed to allow for this usage.)

Important! The dryer is designed to remove only water vapor. You might see a small amount of
condensate forming at the exhaust due to the Joule-Thomson cooling effect created by the depressurizing
air.
Prior to switching a freshly regenerated bed “on-line” to become the drying bed, it must be slowly
pressurized from atmospheric pressure to line pressure. This step is called repressurization.
Repressurization prevents bed fluidization (lifting) and associated dusting.
Following repressurization, the beds switch functions with the fresh bed now drying and the
saturated bed being regenerated.
Note that one bed is always “on-line” drying. Also note that purge air is always being consumed
except during repressurization.
This cycle will continue automatically unless the dryer is shut down, operated in the Cycle Loc mode or
equipped with a Powerloc or Pro Purge.
SECTION 4 Sequence of Operation
The sequence is controlled by a Solid State Timing and Relay circuit (Sequence Annunciator) which in
turn controls five electric solenoid valves. The first four are 3-Way Normally Closed Valves, which
supply control air to operate air operated diaphragm inlet and exhaust valves. The Inlet Valves are
Normally Open and are closed by applying pressure to the top surface of the diaphragm. The Exhaust
Valves are Normally Closed and are opened by applying pressure to the underneath of the diaphragm.
The fifth solenoid is a 2-Way normally closed valve. This is the repressurization valve. There are also
four mechanical check valves, two outlet and two purge, that allow for proper air flow.
STEP 1- LEFT DRYING; RIGHT REGENERATING SOLENOID #1 is de-energized sending no air to
Exhaust Valve #1 (left side). Exhaust Valve #1 is closed.
SOLENOID #2 is de-energized sending no air to Inlet Valve
#1 (left side). Inlet Valve #1 is open. All of the wet inlet air is flowing through Inlet Valve #1. It is dried as it
passes through the left tower desiccant bed and exits out the left side Outlet Check Valve to the dryer
outlet. The left tower is the Drying tower and the associated pressure gauge should read line pressure,
typically 100 PSIG.
At the same time SOLENOID #3 is energized sending a signal to Inlet Valve #2 (right side). Inlet Valve #2
is closed, preventing inlet air flow through the right tower.
SOLENOID #4 is energized sending a signal to Exhaust Valve #2 (right side). Exhaust Valve #2 is open.
(NOTE: When exhaust valve first opens, the associated tower will depressurize from line pressure to
atmospheric pressure.) Purge air will now flow from the dry air outlet through the Purge Adjusting valve,
Purge Orifice and the right hand Purge Check Valve. This purge air then proceeds through the right tower
near atmospheric pressure, removing the moisture and exiting the right hand Exhaust Valve and Muffler in
vapor form (at no time should the dryer expel any significant amount of liquid water from the muffler; this is
a sure sign of trouble in the system). The right tower is the regenerating tower, the associated pressure
gauge should read “0” PSIG.
SOLENOID #5 is de-energized and closed.
STEP 2 - LEFT DRYING, RIGHT REPRESSURIZING
While the left tower is still drying, Solenoid #4 will de- energize, relieving the control air signal on the right
exhaust valve, returning that valve to its normally closed state. Closing this valve keeps air in the tower,
allowing the depressurized part of the dryer to build up pressure or
“repressurize”. At the same time Solenoid #5 is energized and opened, providing additional air to the tank
coming from the purge line to ensure full repressurization of the dryer.
Prior to switching towers, all of the gauges should equalize to line pressure.
STEP 3 - LEFT REGENERATING, RIGHTDRYING

Step 3 is the reverse of step 1. Solenoid #1 is energized, providing control air to and opening the left
exhaust valve.
Solenoid #2 is energized, providing control air to and closing the left inlet valve. Solenoid #3 and #4 are de-
energized. Thus the right inlet is open, and the right exhaust is closed. All the wet air is now flowing
through the right tower and is being dried at line pressure. The left tower is being regenerated at
atmospheric pressure. Solenoid #5 is de- energized and closed.
STEP 4 - LEFT REPRESSURIZING, RIGHT DRYING Step 4 is the reverse of Step 2. Solenoid #1 de-
energizes, allowing the left exhaust valve to close and allowing the dryer to repressurize. In addition,
Solenoid #5 energizes providing additional air for repressurization.
NOTE: The Purge Gauge (middle) should read purge pressure, except during repressurization. Purge
flow is calculated by the Purge Formula in this manual and by checking the proper graph. Purge
pressure for standard inlet design conditions is listed on page 1. For other than standard or design
conditions use the purge formula and charts for purge flow/pressure calculation, or consult the factory.

Sequence of Operation Drawings

Section 5 Start Up
Please read and understand the entire manual before operating the dryer.
Check and read over wiring diagrams that pertain to your unit and make sure the correct power supply
is connected, but do not energize circuit at this time. Provide proper short circuit protection. Follow all
applicable codes.
If you do NOT want the dryer to cycle automatically when energized, close the control air isolation valve.
If the system has already been pressurized, bleed off the control air pressure by opening the knob on
the bottom of the control air filter and reclosing.
Before starting the dryer your compressor should be running, your air system pressurized and the dryer
bypassed and not yet pressurized.
SLOWLY open the inlet isolation valve admitting com- pressed air to the dryer. It is important to
pressurize the dryer slowly to prevent fluidization of the desiccant bed. The dryer outlet isolation valve
should be closed at this time.
SLOWLY open dryer outlet isolation valve. At this point all valves are in “normal” positions; air is
flowing through both towers and downstream.
Close the dryer bypass valve. Bypass valves must be bubble tight to prevent moisture from migrating
around the dryer and contaminating the dry air outlet.
It is required that the dryer be started without the mufflers installed. This will expedite removal of excess
desiccant dust and prevent premature clogging of the exhaust mufflers.
CAUTION: USE EAR AND EYE PROTECTION WHEN OPERATING DRYER WITHOUT MUFFLERS.
EXCESSIVE NOISE WILL BE CREATED. DUST AND PARTICLES FROM THE SURROUNDING
AREA MAY BECOME AIRBORNE. OPERATION WITHOUT MUFFLERS EXCEEDS OSHA LIMITS.
Check the Variable Cycle Control setting. It should normally be set at the standard 10 minute, 100%
load.
Energize the electrical circuit. If the control air valve is open the dryer will begin to cycle.
If the control air valve is closed, open it to begin the dryer cycle. At this point one tower will exhaust its air
to atmosphere. See “CAUTION” statement above.
Check and adjust the setting of the purge pressure indicator or purge flow meter in accordance with the
specifications for your dryer. Normally, purge flow is approximately 15% of design flow for the dryer. Note
that even if you are operating under a light load the purge can not be reduced if you are operating in the
PowerLoc, Pro Purge or Cycle Loc modes, or a fixed timed cycle other than the standard 10 minute,
100% load cycle.
Section 6 Operational Notes
Never service the dryer or filters without first relieving pressure.
Check all air connections for leaks and tighten as required. Downstream air leaks will affect dew point.
Bypass air leaks will affect dew point. Only soft seat bypass valves may be used.
Dryer will not perform without proper pre-filtration, condensate drainage, and purge flow. Dryers may
require up to 48 hours of operation to reach normal operating dew points. Therefore, indicators and/or
alarms should not be recognized until that time. Applications requiring dew points lower than -40°F, or
with nonstandard operating conditions, may require additional time to reach equilibrium.

Exhaust valves and/or exhaust mufflers may have to be cleaned due to dusting in shipping and start-
up.
A desiccant dryer should never be suddenly pressurized or depressurized. This will cause fluidizing and
dusting of the desiccant bed.
After start-up, some dusting may occur. This will diminish with time. Some dusting may occur with
normal operation. The Exhaust Mufflers should be cleaned regularly and an Afterfilter should be used.
Flow direction is Upflow Drying - Downflow Purge. Switching Failure Alarm is optional and the dryer
must be operating over 70 PSI for proper function of the alarm. Dryer valving is “fail-safe” on power
loss. This means the inlet valves open and exhaust valves close, allowing system to remain
pressurized and air to flow through both towers, and down stream.
The standard AIRTEK dryer has been designed for drying service to 150 PSIG.
A repressurization valve is standard on TW- 75 and up. The dryer must repressurize before
switching.
Variable Cycle Control
The AIRTEK heatless dryer is equipped with Variable Cycle Control. This control allows for easy
adjustment to meet varying plant loading. By using this control, the dryer can
be set to one of four standard fixed time cycles, a) standard 100% load (10 minute), b) 75% load (15
minute), c) 50% load (20 minute), d) short cycle -80°F dew point (2-1/2 minute). Complete cycle times
are given below.
Cycle Times (time in minutes: seconds)
PER TOWER TIME
CYCLE TOTAL
TIME DRYING REGEN. REPRESS.
100% Load 10:00 5:00 4:15 0:45
75% Load 15:00 7:30 4:15 3:15
50% Load 20:00 10:00 4:15 5:45
Short (-80) 5:00 2:00 2:00 0:30
The 75% and 50% settings adjust the dryer cycle for inlet conditions where the moisture load is less
than 75% or 50% of design. The short cycle will provide a -40°F to - 80°F dew point when operating at
or below design conditions. Always set the purge as if you had a full inlet flow when using these 3
cycles. The cycles automatically compensate for the light loading; there is no need to turn the purge
down. The dryer must be operated in the standard 10 minute 100% load cycle when equipped with a
Pro Purge.
Section 7 Shutdown Procedures
Isolation
1. Allow dryer to reach repressurization step and fully repressurize
2. While fully repressurized, remove power from the dryer by turning off disconnect.
3. Open bypass pipe.
4. Close outlet isolation valve.
5. Close inlet isolation valve.

Depressurization
1. Open bypass piping.
2. Close outlet isolation valve.
3. Close inlet isolation.
4. Allow dryer to run. The normal cycle will allow both tanks to blow down and depressurize.
5. Disconnect power.
6. With the “Basic Filter Package” dryers, open manual ball valves on filters to allow full
depressurization. Leave ball valves on filters open while servicing. Without the “Basic Filter
Package”, close control air filter off. Remove nylon tubing from control air filter or any control
solenoid. Reopen control air filter to fully depressurize. Leave control tubing off while servicing.
To restart, follow “Start-Up” procedure on page 8. IMPORTANT! Always remove all pressure and
disconnect all power before servicing the dryer.
IMPORTANT! If a Pro Purge or Powerloc is installed and the dryer will be out of service for an extended
period of time, remove the probe and store in a safe, dry location. The probe will be damaged if
exposed to prolonged periods of saturated conditions.
Section 8 Demand Cycles
Cycle Loc, Pro Purge and Powerloc are demand cycles available for any heatless dryer. Cycle Loc is
standard on all heatless dryers (75 SCFM & Up). Powerloc and Pro Purge is an option that needs to be
purchased. These cycles offer improved operating efficiency over fixed time cycles for applications
requiring a -40°F dew point and that will see lighter than design moisture loading. Demand cycles
reduce total purge consumption and thus reduce energy usage by tailoring the cycle to actual loading,
vs., fixed cycles which assume 100% design loading. Demand cycles can not accommodate for heavier
than design loading. It can not shorten the fixed cycle, only lengthen it.
Cycle Loc
The Cycle Loc feature is built into TW75 and up models. It can be used to interface the dryer with the
air compressor. The dryer must be able to handle at least full flow of the compressor and the receiver
should ideally be located downstream of the dryer. A dry (un-powered) contact closure across the Cycle
Loc terminals on the Sequence Annunciator will cause the dryer to immediately pause its cycle and stop
purging. The contact closure needs to correlate with the compressor stopped or unloaded. When the
contact opens, the dryer will resume where it left off. Typically a contact on the compressor control is
utilized. If a dry, normally open (with compressor running) contact is not available; an auxiliary relay will
need to be added. The cycle selector needs to be set on “Cycle F” for correct Cycle Loc operation.
Please consult factory for any questions.
Pro Purge
The Pro Purge is an advanced Sequence Annunciator and Proportional Demand Control. The probe
is a thin film gold aluminum oxide design. The Pro Purge probe monitors the outlet pressure dew
point of the dryer and displays the dew point range via three LED indicating lights which are as
follows:
-40 = Dew points at -40°F or greater
-30 = Dew points between -39 to -21°F
-20 = Dew points at -20°F or less
The Proportional Demand Cycle Control feature tailors the dryer cycle to actual loading conditions,
maximizing energy usage. Without the Pro Purge the cycle is fixed and “worst case” design conditions
are assumed.
The Proportional Demand Cycle is accomplished by the probe providing an input to the Sequence

Annunciator. The Variable Cycle Switch must be set to the 100% load setting and the Demand Control
switch ON, for the Pro Purge to work! If the dryer is maintaining a good dew point AFTER the first five
minutes of drying, the Pro Purge will override the fixed cycle and keep the current tower on-line until it is
saturated to design loading (switch point value), usually -40°. If this occurs, the Powersaver Active light
and the -40 light on the Sequence Annunciator will be on and the off-line bed which has just finished
being regenerated will repressurize and be ready to go on-line. Once the dew point degrades to the
switch point value, the freshly regenerated bed will go on-line, and the saturated bed will depressurize
and begin regeneration. Note that the Pro Purge can not shorten the cycle. The drying tower will always
be on-line a minimum of five minutes and the regenerating tower will always undergo a design
regeneration cycle of 4 minutes & 15 seconds. Thus the Pro Purge can only compensate for “under”
loading, not overloading conditions.
If there is any error with the Pro Purge sensor or cable the alarm light only will be lit and the dryer will
default to the fixed time cycle. If the dew point is -20 the alarm light will be on as well. There is also a
Demand Control On/Off switch located on the Sequence Annunciator. If this switch is turned “off” the
dryer will operate in the fixed time cycle. The Pro Purge will continue to display dew point. The Pro
Purge is fully programmed, wired and installed at the factory if ordered with the dryer.
For dryer start-up, all that is normally required is a 24 hour run period for the dryer before the isolation
valve to the probe is open. This assures the sensor will see dry air for its first exposure to the system.
Dryers Equipped with a Powerloc
The Powerloc is a Digital Dew Point Monitor. The sensor is a thin film gold aluminum oxide design. The
Powerloc monitors the outlet pressure dew point of the dryer and digitally displays it. The Powerloc
feature tailors the dryer cycle to actual loading conditions, minimizing energy usage. Without the
Powerloc, the cycle is fixed and “worst case” design conditions are assumed.
The Demand Cycle is accomplished by providing a discrete dry contact closure across the Cycle Loc
terminals on the Sequence Annunciator. The Variable Cycle Control Switch must be set to 100% load
setting for the Powerloc to work. If the dryer is maintaining a good dew point AFTER the first five
minutes of drying, the Powerloc will override the fixed cycle and keep the current tower “on-line” until it is
saturated to design loading (switch point value), usually -40°F. If this occurs, the “off- line” bed which has
just finished being regenerated will repressurize and be ready to go “on-line”. The Cycle Loc light on the
Sequence Annunciator and the Powerloc will be on at this time. Once the dew point degrades to the
switch point value, the freshly regenerated bed will go “on-line”, and the saturated bed will depressurize
and begin regeneration. Note that the Powerloc can not shorten the cycle. The drying tower will always
undergo a design regeneration cycle of 4 minutes and 15 seconds. The Powerloc can only compensate
for under-loading, not overloading conditions.
If there is any error with the Powerloc, the dryer will default to the fixed time cycle. There is also a
Powerloc On/Off switch located in the control enclosure. If this switch is turned off the dryer will operate
in the fixed time cycle. The Powerloc will continue to display dew point. The Powerloc is fully
programmed and wired at the factory if ordered with the dryer.
For dryer start-up, all that is normally required is sensor installation. The sensor should be installed after
dryer has been allowed to purge the initial dusting caused by transportation or filling. The probe
isolation valve should be fully opened after installation to allow operations at full line pressure for correct
reading of pressure dew point. A coil of capillary tubing is provided to allow a small sample flow over
the sensor and prevent ambient moisture from infiltrating the system. Check the bleed periodically to
ensure it is not clogged.
Following sensor installation, allow the sensor to stabilize at the line pressure for four hours prior to
attaching the sensor cable.
Failure to follow the above precautions may result in sensor failure not covered by warranty.
Please note that upon installation the sensor will be saturated at atmospheric conditions. Even if the
dryer is producing a good dew point, it will not be indicated immediately as it will take a period of time
for the sensor to dry out and come to equilibrium with the system.
The sensor will also become saturated to atmospheric conditions if the air system is shut down and

allowed to depressurize. Upon restart of the system, the dew point may appear to be poor, even
though the dryer may be producing clean, dry air.
Although the probe can be exposed to occasional, brief periods of liquid saturation, it can not be
exposed to continuous wet conditions. If your dryer is over loaded and saturated, or if it will be shut
down for an extended period of time; remove or isolate the probe until the problem is resolved. Refer
to the separate Powerloc section for more detailed information.
IMPORTANT! Demand Control Cycles can not be used together! Please consult factory to insure
proper use of any of the nonstandard cycles.
MODEL CAPACITY PSI CFM COLOR SIZE DES/TOWER IN/OUT CON
TW 10 10 0 1.5 N/A N/A 7 3/8" NPT
TW 15 15 0 2.25 N/A N/A 7 3/8" NPT
TW 25 25 31 3.75 BLUE 3/32" 17 1/2" NPT
TW 40 42 63 6.3 BLUE 3/32" 23 1/2" NPT
TW 55 60 48 9 GOLD 1/8" 35 3/4" NPT
TW 75 75 65 11.3 GOLD 1/8" 45 3/4" NPT
TW 100 107 37 16.1 GREEN 3/16" 60 1" NPT
TW 130 135 50 20.3 GREEN 3/16" 75 1" NPT
TW 200 200 40 30 RED 1/4" 120 1 1/2" NPT
TW 250 250 29 37.5 BROWN 5/16" 150 1 1/2" NPT
TW 300 300 37 45 BROWN 5/16" 175 1 1/2" NPT
TW 400 400 34 60 YELLOW 3/8" 240 2" NPT
TW 500 500 46 75 YELLOW 3/8" 300 2" NPT
TW 600 650 43 97.5 SILVER 7/16" 350 2" NPT
TW 770 800 56 120 SILVER 7/16" 475 2" NPT
TW 1000 1000 53 150 WHITE 1/2" 600 3" FLG
TW 1200 1250 39 188 BLACK 5/8" 700 3" FLG
TW 1500 1500 51 225 BLACK 5/8" 1030 4" FLG
TW 2000 2200 51 330 LT BLUE 3/4" 1200 4" FLG
TW 2600 2600 29 390 ORANGE 1" 1550 4" FLG
TW 3000 3000 36 450 ORANGE 1" 1775 6" FLG
TW 4000 4000 53 600 ORANGE 1" 2375 6" FLG
Purge Flow 15% Heatless
NOTE - TW5000 and up, please contact factory.
Dryer Outlet Flow
Dryer outlet flow is equal to the dryer inlet flow minus the purge flow.
Dryer Capacity
Checking Dryer Size:
A. Determine operating pressure.
B. Determine input SCFM into dryer.

Read down the nearest operating pressure column until you arrive at a rating equal to or greater than
your equipment; then read to the left for dryer model
TW75 60 80 100 120 140
TW100 49 62 75 88 101
TW130 70 8 107 126 144
TW200 88 111 135 159 182
TW250 130 165 200 235 270
TW300 163 206 250 294 337
TW400 195 248 300 352 405
TW500 261 330 400 470 540
TW600 332 421 510 599 688
TW800 524 661 800 940 1079
TW1000 651 826 1000 1175 1359
TW1200 782 991 1200 1410 1619
TW1500 975 1239 1500 1762 2024
TW2000 1303 1652 2000 2350 2698
TW2600 1694 2147 2600 3054 3508
TW3000 1954 248 3000 3524 4048
TW4000 2600 3300 4000 4600 5400
TW5000 3200 4100 5000 5800 6700
Heatless
Model PRESSURE
EXAMPLE: You want to dry 95 SCFM at 80 PSIG - go to the 80 PSIG column and read down to 111 (this
is the first number equal to or greater than your requirement). Now read the dryer model number to you
left. A model TW-130 is required.
Sizing is approximate only. Consult factory for exact sizing. Downsizing could cause pressure
rop, bed fluidization, or poor dew point performance due to low contact time.d
The previous chart assumes 100°F or less inlet air temperature.

Section 9 Maintenance Program
Daily
1. Check dew point or humidity level if instrumentation is available. Any difficulty with the dryer will result in
poor dew point performance.
2. Check for correct purge setting and air flow from purge exhaust.
3. Check gauge readings and sequence of operation through complete cycle.
4. Check auto drain operation on pre-filter, separator and receiver. A manual drain valve installed (in
addition to the automatic drain) at these points will ease checking of the automatic drains.
5. Ensure there is no back pressure in the regenerating tower.
Weekly
1. Check differential pressure across pre-filter and afterfilter elements. Replace if required.
2. Check and maintain operating conditions; pressure, flow, and temperature within the design parameters
of the dryer.
Semi-Annually
1. Inspect desiccant for physical condition. Desiccant from a freshly regenerated bed should be white, dry to
touch and of consistent size and shape. If desiccant condition is in question, send a sample to AIRTEK
for analysis.
2. Check and clean mufflers. This may be required often under certain conditions or if back pressure
develops. Mufflers can be cleaned by blowing backwards through them with clean, dry air. Mufflers may
require replacement if severely clogged, or after a few cleanings.
3. Replace pre-filter and afterfilter elements.
4. Clean automatic drain.
5. Replace Control Air Filter Element.
6. Check and Slowdown Safety Valves. Refer to manufacturer’s instructions.
7. Clean dryer.
Annually
1. Inspect and rebuild Inlet and Exhaust Valves.
2. Clean Control Solenoid Valves.
3. Return Powerloc Probe and chip for recalibration, if applicable.

Desiccant Replacement
CAUTION: Activated Alumina Desiccant dust is considered a nuisance dust. Proper precautions
should be taken. Refer to “Material Safety Data Sheet”.
1. Remove pressure and power from dryer.
2. Open drain ports on bottom of tanks.
3. Catch desiccant in suitable container. Close drain ports and open top fill ports.
4. Refill with recommended type, size and quantity of desiccant. Rap sides of the chambers while
filling so desiccant will pack tightly. Some settling may be required to fit specified amount in tank.
One tank size may be used for multiple models, do not be concerned if tank is not full.
5. Consult Material Safety Data Sheet and all applicable regulations for disposal of desiccant.
Disposal of desiccant contaminated with oil or other substance may require different procedures
than desiccant replaced strictly due to aging.
NOTE: Use only AIRTEK Desiccant which is a high capacity, high quality desiccant designed and
sized for AIRTEK dryers.
MODEL DESICCANT LBS./TOWER
TW75 44 Lbs.
TW100 60 Lbs.
TW130 75 Lbs.
TW200 120 Lbs.
TW250 150 Lbs.
TW300 175 Lbs.
TW400 230 Lbs.
TW500 300 Lbs.
TW600 350 Lbs.
TW800 475 Lbs.
TW1000 600 Lbs.
TW1200 725 Lbs.
TW1500 1030 Lbs.
TW2000 1200 Lbs.
TW2600 1550 Lbs.
TW3000 CF
TW4000 CF
TW5000 CF
Inlet and Exhaust Valve Repair
Request valve cutaway if required. These valves offer simple in-line serviceability. Special tools may
be required, consult factory if tools are desired.
1. Shutdown the dryer as described on page 7. Remove pressure from the dryer. Make certain there
are no “pockets” of pressure isolated by various valves. Open the bleed valve on the bottom of the
control air filter bowl.
2. Loosen the compression fitting attaching the control tubing to the valve body. Carefully move the
tubing aside.
3. Loosen and remove the bonnet hex head cap screws and nuts. Remove the bonnet.

4. Remove the locknut and washer from the shaft. A screw driver slot is provided at the end of the
shaft to prevent it from rotating while removing this nut.
5. The diaphragm plates and diaphragm can now be removed. Make note of the curvature of the
diaphragm plates.
6. Remove the O-ring retainer. This may require a special tool or a deep well socket, depending on
valve size. You can now remove the disk, holder and shaft.
7. Remove the brass seat. A special tool may be required.
8. Reassembly is reverse of disassembly. Replace ALL the O-rings, seat and diaphragm as you go.
A very light application of an anti-seize product on threads of the brass seat and O-ring retainer
will make future repairs easier. Do not neglect the shaft O-rings which are internal to the O-ring
retainer.
Section 10 Parts (General Parts Description)
A. DESICCANT - An adsorbent used for drying air or gases. Proper quantity, size and type are
necessary.
B. INLET SWITCHING VALVES - Normally Open Air Operated Diaphragm Valves used to direct the air
flow through the towers.
C. EXHAUST VALVES - Normally Closed Air Operated Diaphragm valves used to exhaust purge air, hold
air in tower on line, and exhaust air from tower ready to be regenerated.
D. OUTLET AND PURGE CHECK VALVES - Valves that allow full flow in one direction and no flow in the
other are used in conjunction with the inlet and exhaust valve to accomplish desired flow of process and
purge air.
E. SAFETY RELIEF VALVES - Furnished on each tower to protect the vessels from overpressure
situations. Standard setting is 150 PSIG.
F. PURGE EXHAUST MUFFLER - Furnished to reduce exhaust noise during purge and blow down for
personnel protection and to comply with OSHA standards. Mufflers offer no benefit to the operation of
the dryer and are a maintenance concern. Consideration should be given to locating the exhaust in an
area where mufflers would not be required.
G. PURGE CONTROL REGULATOR OR VALVE- Furnished to adjust and regulate purge flow
for generation.
H. SOLID STATE CONTROLLER/SEQUENCE ANNUN- CIATOR PANEL - Furnished for cycle control.
Outputs operate 5 electric solenoid valves. Provides for Variable Cycle Control. Provides interface with
optional Powerloc and has integral lights to provide visual cycle indication. Has built-in automatic drain
control. All hard wired connections, including field power connection, are made to this board.
I. TOWER PRESSURE GAUGES - Furnished to read pressure in each tower. On-line tower should
read line pressure, regenerating tower should read “0” PSIG.
J. PURGE FLOW INDICATOR (center gauge) - Furnished to indicate and monitor proper purge
flow.
K. CONTROL SOLENOIDS - (4) 3-way normally closed electric solenoid valves, operated by the solid
state controller, that in turn provide a control air signal to operate the inlet and exhaust valves.
L. REPRESSURIZATION SOLENOID (Variable Cycle Control Bypass) - A 2-way normally closed
electric solenoid valve provided to insure tower repressurization before switching, even at low flows.
M. CONTROL AIR FILTERS - Filters control air, which is taken from the dryer outlet, to protect the control
solenoids from desiccant dust. Also protects Powerloc Probe where applicable.

Section 10, cont. Spare Parts Lists
QTY. PART # Recommended
Spare Maintenance Interval DESCRIPTION
2 TP7610-P1 VALVE, 1" POPPET INLET VALVE
2 TP7610-P1-RK X 1 year REPAIR KIT, 1" POPPETINLET VALVE
2 TP7510-P1 VALVE, 1" POPPET EXHAUST VALVE
2 TP7510-P1-RK X 1 year REPAIR KIT, 1" POPPETEXHAUSTVALVE
2 TP7105 VALVE, SAFETY RELIEF 1/2"
2 TP7403-C VALVE, 3/8" PURGE CHECK VALVE
2 TP7403-RK1 X 1 year REPAIR KIT, 3/8" PURGE CHECK VALVE
2 TP7407-C VALVE, 3/4" CHECK VALVE
2 TP7407-RK1 X 1 year REPAIR KIT, 3/4" CHECK VALVE
4 TP8101-1 X SOLENOID, INLET & EXHAUST CONTROL
2 TP4210 X 1 year MUFFLER, EXHAUST 1"
1 TP2201-P FILTER, CONTROL AIR
1 TP2201-PE X 1 year ELEMENT, CONTROL AIR
3 LP1020 GAUGE, TOWER PRESSURE
88 LBS TP3001 3-5 years DESICCANT, ACTIVATED ALUMINA
1 TP9020 MOISTURE INDICATOR
1 TP8002 REPRESSURIZATION SOLENOID
1 TP8001-CO X SOLENOID COIL
1 TP4605 PURGE REGULATOR
1 TP2577-GNRC X CONTROL BOARD, STANDARD
1 TP2188 PRO-PURGE PROBE
1 TP2578 X CONTROL BOARD, PRO-PURGE
1 TP2190-1 DEWPOINT PROBE
1 TP2191-2 DEWPOINT ANALYZER
1 TP8002 DRAIN SOLENOID
1 TP8001-CO X SOLENOID COIL
1JE-CC0110 X3-6 MONTHS COALESCER PREFILTER ELEMENT
1 JE-FC0110 X3-6 MONTHS PARTICULATE AFTER FILTER ELEMENT
75 CFM
Spare Parts List
OPTIONAL EQUIPMENT
Note - Standard Units- For Non-Standard, please consult factory