Pneumatech AD-1500 User manual

Printed in U.S.A. Publication No. OM-A-75
March 2006 Rev. 4
Owner’s Manual
N ON
-
CYCLING
R
EFRIGERATED
A
IR
/G
AS
D
RYER

To receive Extended Warranty, you must regis-
ter on line at: www.pneumatech.com.
Doing this will extend the warranty to 24
months from date of shipment from Company’s
factory. See back page for actual Warranty
details.
DATE OF PURCHASE
MODEL
SERIAL NO.
Record above information from nameplate.
Retain this information for future reference.
Replacement Price $25.00

Pub. No. OM-A-75 REV. 4 — March 2006
1
TABLE OF CONTENTS
Page
General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Safety Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Disclaimer of Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Installation Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Start-Up and Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Design Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Start-Up Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Operating Range and Control Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Digital Dry Guard™ (DDG) Controller Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Shutdown Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Air Dryer Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Automatic Drains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Compressor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Expansion Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Hot Gas Bypass Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Refrigerated Air Dryer Service CheckList . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

2
Pub. No. OM-A-75 REV. 4 — March 2006
GENERAL INFORMATION
The Pneumatech Air Drying System is designed to cool
and remove moisture from compressed air.
When properly installed, the unit requires little
maintenance or adjustment.
This manual contains important safety information. Read
THOROUGHLY and follow the Safety Instructions provided
in this manual and posted on the unit. Keep this manual
near the unit and in a safe place. Replace this manual if it
becomes torn or dirty and cannot be properly used.
Please read the Installation Instructions and Start-up and
Operation sections of this manual before attempting to
operate the unit.
Please read the Maintenance and Troubleshooting
sections of this manual before beginning any maintenance
or service work on this unit.
INSPECTION
Inspect equipment. Any concealed shipping
damage must be reported to the carrier
immediately. Damage claims should be filed by
the consignee with the carrier.
SAFETY INSTRUCTIONS
When using air compressors and compressed air
accessories, basic safety rules and precautions must
always be followed, including the following:
1. READ ALL INSTRUCTIONS FULLY.
2. WIRING & BREAKERS
Wiring, breakers and other electrical equipment
must conform to local and national electrical codes.
Do not operate this unit with damaged wiring or
after the unit or air handling parts have been
dropped or damaged in any manner. Notify
authorized service facility for examination, repair
or other adjustments.
3. USE SUITABLE PARTS & ACCESSORIES
Do not use air pressurized accessories or parts in the
air system not suitable for the maximum air pressure.
4. RELEASE AIR PRESSURE SLOWLY
Fast moving air will stir up dust and debris, which
may be harmful. Release air pressure slowly when
depressurizing your system to avoid bodily injury.
5. SECURE DRAIN LINES
Fasten drain lines to floor or drain. Pressurized air
may periodically pass through drain lines, which will
cause an unsecured line to whip and may cause
bodily injury.
To provide safe, breathable air, compressor must be
capable of producing at least Grade D breathing air as
described in Compressed Gas Association Commodity
Specification G7.1-1966. Special filtering, purifying and
associated alarm equipment must be used to convert
compressed air to “Breathing Air.” Other special
precautions must also be taken.
Refer to OSHA 29 CFR 1910.134.
DISCLAIMER OF WARRANTY
If this unit is used to produce breathing air, the special
equipment and precautions expressed in OSHA 29 CFR
1910.134 for specifications of the necessary equipment
and special precautions to make Breathing Air MUST BE
used or any warranties are VOID and manufacturer
disclaims any liability whatsoever for loss, personal injury
or damage.
DO NOT install, operate, maintain, adjust
or service this unit without thoroughly
reading this manual.
Air from compressor and from Pneumat-
ech Air Drying System, as equipped, is not
safe for human respiration (breathing).

Pub. No. OM-A-75 REV. 4 — March 2006
3
INSTALLATION INSTRUCTIONS
FIGURE 1 — COMPRESSED AIR SYSTEMS RECOMMENDED INSTALLATION FLOW DIAGRAM
CO
MPRE
SS
ED AIR
S
Y
S
TE
M
RE
CO
MMENDED IN
S
TALLATI
ON
FL
O
W DIA
G
RA
M
PA
R
PR
DIFFERENTIAL
PRE
SSU
RE
G
A
UGE
DIFFERENTIAL
PRE
SSU
RE
G
A
UGE
4
AFTER
COO
LE
R
1
3
PLANT
AIR
-4
0
°
F T
O
-1
00
°
F PDP
R
-
RELIEF VALVE
P - PRE
SSU
RE
G
A
UGE
T - TEMPERAT
U
RE
G
A
UGE
(
REMOVES 66
%
MOISTURE
)
AIR
COO
LE
D
AFTER
COO
LE
R
2
P
RE
C
EIVE
R
T
C
PREFILTER
RE
G
ENERATIV
E
AIR DRYER
PARTI
CU
LAT
E
AFTERFILTER
4
5
T
O
PLANT
USE
37
°
°
°
F
RE
C
EIVE
R
REFRIGERATED
CO
ALE
SC
IN
G
AFTERFILTER
DRAIN
R
O
PTI
O
NAL
3
VALV
E
S
Y
S
TEM BYPA
SS
P
6
P
CONTROL
(
OPTIONAL
)
AUTO
DRAI
N
1. SEE PNEUMATECH BULLETIN PWC-1 2. SEE PNEUMATECH BULLETIN A-3 3. SEE PNEUMATECH BULLETIN A-16 4. SEE PNEUMATECH BULLETIN A-8 5. SEE PNEUMATECH BULLETIN A-10 6. SEE CONSERVAIR BULLETIN CA-200
44
AU
DIFFERENTIAL
PRE
SSU
RE
G
A
UGE
DIFFERENTIAL
PRE
SSU
RE
G
A
UGE
4
77
TO
AIN
3
A
U
T
O
DRAIN
3

4
Pub. No. OM-A-75 REV. 4 — March 2006
A. Install the dryer INDOORS in an area where the
ambient temperature will be above 55°F and below
100°F. Temperatures below 55°F and above 100°F
may cause erratic operation of the air dryer.
Air-cooled dryers must be installed INDOORS in a
location with proper ventilation which will maintain
ambient temperatures as specified above.
B. Position the dryer to permit free circulation of cooling
air through the condenser. Keep two feet minimum
clearance space around the dryer, and also on the
top for servicing.
Lack of ventilation can build up the room
temperature by recirculating the same cooling air
through the condenser over and over again. This will
eventually shut down the refrigerant compressor on
high head pressure and/or on internal overload.
C. Connect the compressed air to the dryer inlet.
Connect the plant compressed air line to the dryer
outlet. A three-valve bypass around the dryer is
recommended for dryer service. See Figure 1. A
coalescing afterfilter is recommended for oil-flooded
air compressor systems.
D. 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. Also, properly support the pipes as needed
with hangers or brackets. Air piping must be
installed by an experienced pipefitter.
E. An aftercooler (air-cooled or water-cooled) must be
installed between the air compressor and the dryer.
Installing the dryer without the proper aftercooler will
bring high inlet temperature compressed air to the
air dryer which will cause premature failures.
Aftercoolers must be followed by a separator and an
automatic drain to remove the condensed moisture
before the compressed air reaches the air dryer.
If the condensed water is not removed at the
aftercooler separator drain, it will reduce the cooling
capacity of the air dryer. Aftercoolers will condense
approximately 2-1/2 to 3 times more water than that
of the air dryer.
F. Float type auto drains are installed on dryer models
AD-10 through AD-50. For models AD-75 through
AD-3200 electronic timer operated drains are
standard. Dryers AD-75 and larger include a
particle strainer upstream from the drain valve.
To clean, close the shut-off valve and depressurize
the drain line.
All drain outlets may be combined for condensate
disposal. Dispose the condensate in compliance to
local and federal government requirements.
G. For water-cooled air dryers, connect cooling water
lines to the water-cooled condenser from the water
supply. Water pressure must be a minimum of
35 PSIG.
Do not connect city water to a condenser which is
piped for tower water or vice versa. Strainers are
recommended at the water inlet to the condenser.
Proper chemical treatment is recommended for
cooling tower water to avoid scaling and sludge
inside the condenser.
Drain outlet tubing will periodically con-
tain pressurized air. An unsecured drain
tube will whip around potentially causing
bodily injury.
Do not combine any two or more drain inlet
lines through one single automatic drain
valve. This will reduce or eliminate the
proper drainage.
Do not reduce pipe sizes connected to water
and drain lines. They should be the same or
larger than sizes supplied on the dryer to
avoid excess pressure drop.

Pub. No. OM-A-75 REV. 4 — March 2006
5
H. Connect electric power, according to the wiring
diagram and nameplate power requirements, to the
electrical terminals. The refrigerated dryer is
designed to run continuously; therefore, it must be
wired separately from the air compressor cycling
switch. The dryer must not cycle with the air
compressor. All units are prewired internally.
Follow the recommendation on the electrical
drawing for the fuse size and the incoming power
details. Connect the power to the air dryer only
through a properly sized fused disconnect switch.
Wiring to the dryer must meet the national
(NEC) and local code requirements. Check
the voltage specified on the nameplate to
the electrical power connecting to the
dryer. Electrical connections must be made
by an electrician.
SCROLL COMPRESSOR
Air dryers with a scroll compressor are uni-
directional and to function properly they
must be phased correctly. To turn the com-
pressor clockwise, use a phase sequence
indicator to determine phases A, B, & C. For
proper compressor rotation, connect the
power supply phases A to L1, B to L2, & C to
L3. Reverse rotation may damage the com-
pressor. If the compressor is wired back-
wards the compressor will be noisy, vibrate
excessively and the oil sump will become
warm. The suction pressure will begin to
rise, and the discharge pressure will fall.

6
Pub. No. OM-A-75 REV. 4 — March 2006
START-UP AND OPERATION
The non-cycling design of the refrigerated dryer assures
proper dew point control at all load conditions. The
refrigerant compressor runs continuously when the dryer is
“ON”. All dryers are installed with fan cycling switches.
These fans will cycle with respect to the load changes,
ambient temperature fluctuations, and the cleanliness of
the condenser. Standard units are designed to operate
under the following conditions:
DESIGN CONDITIONS
1. Inlet Air Temperature:
100°F design 120°F maximum
2. Inlet Air Pressure:
100 PSIG design 150 PSIG maximum
3. Ambient Air Temperature:
55°F minimum 100°F maximum
4. Cooling Water Temperature:
90°F maximum
5. Cooling Water Pressure:
35 PSIG minimum 100 PSIG maximum
At temperatures above the 100°F design, refrigeration
capacity will decrease. Operating air pressures below the
100 PSIG design will reduce system capacity.
START-UP PROCEDURE
1. If the suction pressure gauge reads zero, refrigerant loss
has occurred. Call the factory or distributor for service.
2. Air dryers with three-phase power supply
are equipped with a compressor crankcase
heater (except scroll compressors). This
heater must be energized by closing the
disconnect switch or circuit breaker a
minimum of 6 to 10 hours before start-up.
Power to the air dryer can be left on to
energize the crankcase heater for the off-
cycle, during evening or weekend
shutdowns.
3. Check the temperature on the crankcase of the
compressor to make sure the crankcase heater is
working before starting the dryer.
4. For water-cooled Air Dryers (ADW) make sure the
water supply (Minimum Pressure 35 PSIG) is
available at the condenser inlet. The water
regulating valve will modulate and control the water
flow with respect to the dryer load conditions. The
water-cooled condenser drain plug (located inside
enclosure) must be installed.
5. For open frame design units [Models AD(W)-1500 &
larger], the following valves must be open prior to
start-up. All valves are tagged with specific
instructions.
a. Compressor isolation valves (suction & discharge
service valves).
b. Receiver valve(s) (air-cooled models only).
c. Condenser outlet liquid line valve (water-cooled
models only).
STARTING THE DRYER WITHOUT ENERGIZING
THE CRANKCASE HEATER WILL CAUSE PREMA-
TURE FAILURES OF THE REFRIGERANT COM-
PRESSOR. Failure to comply with procedure of
energizing crankcase heater before start-up
may void warranty.
CRANKCASE HEATER
Air dryers with three-phase power supply
are equipped with a compressor crankcase
heater. This heater must be energized by
closing the disconnect switch a minimum of
6 to 10 hours before start-up. Power to the
air dryer can be left on to energize the
crankcase heater for off-cycle, during
evening or weekend shutdowns (except
scroll compressors).

Pub. No. OM-A-75 REV. 4 — March 2006
7
d. Hot gas line valve – Models AD(W)-2500 &
larger. Located on the hot gas line before the Hot
Gas Bypass Valve.
e. Liquid line valve on water-cooled condenser
outlet (water-cooled models only).
6. Turn the power ON/OFF switch to the ON position.
7. The suction pressure will gradually come down to the
blue or green range depending on the type of
refrigerant used in the air dryer. Check the
refrigerant suction pressure gauge reading. If the
suction pressure is above or below the suggested
color range, a hot gas bypass valve adjustment is
required. (Refer to the Hot Gas Bypass Valve section
of this manual.) For proper operating range and
control settings see listing below.
8. The Expansion valve is factory set for the correct
superheat of 8-10°F and should not be re-adjusted. If
any malfunction is noticed on the expansion valve,
contact the factory or your Pneumatech distributor.
9. Allow 10 to 15 minutes of cooldown time before
adding the compressed air load.
10. Keeping the dryer outlet isolation valve closed,
pressurize the dryer to the line pressure. See
Figure 1.
11. Check for any leaks in the system.
12. Slowly open the dryer outlet isolation valve to
pressurize the downstream system.
OPERATING RANGE AND CONTROL
SETTINGS
1. Refrigerant Suction Pressure:
53 to 60 PSIG (Refrigerant-22)
(R-22 Green color range)
25 to 33 PSIG (Refrigerant-134a)
(R-134a Blue color range)
2. Refrigerant Discharge Pressure (R-22):
135 to 275 PSIG (R-22) air-cooled units with fan
cycling; 190 to 210 PSIG (R-22) water-cooled units
3. Refrigerant Discharge Pressure (R-134a):
75 to 170 PSIG (R-134a) air-cooled units;
115 to 135 PSIG (R-134a) water-cooled units
4. Refrigerant Low Pressure Switch:
CUT OUT 20 PSIG (R-134a)
CUT IN 40 PSIG (R-134a)
CUT OUT 45 PSIG (R-22)
CUT IN 70 PSIG (R-22)
5. Refrigerant High Pressure Switch:
250 PSIG (R-134a) air-cooled units
405 PSIG (R-22) air-cooled units
(375 PSIG*) (R-22) air-cooled units
(325 PSIG*) (R-22) water-cooled units
6. Fan Control (R-134a):
CUT OUT 110 PSIG
CUT IN 150 PSIG
7. Fan Control #1 (R-22):
CUT OUT 175 PSIG (180 PSIG*)
CUT IN 230 PSIG (220 PSIG*)
8. Fan Control #2 (R-22):
CUT OUT 195 PSIG (190 PSIG*)
CUT IN 250 PSIG (230 PSIG*)
* Settings indicated in parentheses are for units equipped
with adjustable pressure switches.
Consult factory for pressure switch settings on dryers
equipped with optional Low Ambient Headmaster control.
DIGITAL DRY GUARD™ (DDG)
CONTROLLER OPERATION
(Available on some models as standard and others as an
option.)
The DDG Controller is capable of 4-channel temperature
display, drain control, and service due and alarm
indication.
Temperature Display
The DDG controller is capable of 4-channel temperature
display. The unit displays refrigerant suction temperature
(measured immediately downstream from the refrigerant/
air heat exchanger), incoming air temperature, ambient
air temperature (or incoming water temperature for units
with a water-cooled condenser), and dew point
temperature (optional). Only one temperature can be
displayed on the LCD screen at a time. In the normal
operational mode, pushing the UP ( ↑ ) or DOWN ( ↓ )
arrow keys will cycle the temperature displayed, while

8
Pub. No. OM-A-75 REV. 4 — March 2006
LEDs on the DDG unit indicate which temperature is being
displayed. Pushing the SELECT key will cycle between
Fahrenheit and Celsius temperature scales. The LED
labeled “OPTIONAL” corresponds to the dew point
temperature. If your unit does not include this option, the
temperature displayed when the “OPTIONAL” LED is lit
will be about 30° by default. This does NOT indicate that
the dew point is actually 30°.
Drain Operation
Locking/Unlocking Drain Time Settings: The ON
TIME and OFF TIME settings for all modes of drain
operation can be unlocked or locked to avoid inadvertent
changes to these settings. In the unlocked condition, the
time settings will flash after the SELECT key is pressed
momentarily, indicating that the values can be changed by
pressing the UP (
↑ )or DOWN ( ↓ ) arrow keys. In the
locked condition, the SELECT key must be held down for 5
seconds before the display will flash and the settings can
be changed. With the display flashing, pushing the
SELECT key momentarily will return to normal unlocked
operation and holding the SELECT key down for 5
seconds will return to normal locked operation.
Setting Drain ON TIME and OFF TIME:
1. Press the UP ( ↑ ) or DOWN ( ↓ ) arrow keys until the
LED indicates that ON TIME or OFF TIME has been
selected.
2. Press SELECT momentarily (if unlocked) or hold until
the display starts flashing (if locked). If you do not
know whether the setting is locked or not, simply
press the select button momentarily. If the digits on
the LCD display do not start flashing, the setting is
locked.
3. Press UP ( ↑ ) or DOWN ( ↓ ) arrow keys to change the
settings. The ON TIME is indicated in seconds and
changes in 0.5-second increments in a range of 0 to
60 seconds. The OFF TIME is indicated in minutes
and changes in 0.5-minute increments in a range of
0 to 60 minutes.
Modes of Drain Operation: The DDG Controller has
two modes of drain operation for different drain types. The
mode of operation for timed drains (i.e. 4477 A, B, or C
models) is described below as item “A.” The mode of
operation for fully automatic float operated drains (i.e.
model 4488) is described as item “B.” For all modes, the
“DRAINS POWER ON” LED indicates that the drain is
receiving power. Pushing the DRAIN TEST key will send
power to the drain if it is not already receiving power.
A. Timed Drain Mode (model 4477 A, B, or C drains):
Set ON TIME and OFF TIME to non-zero values.
Settings should be such that fluid is adequately
drained without allowing excessive air loss.
B. Demand Drain Mode (model 4488 drains):
Set ON TIME and OFF TIME to zero. Drain is given
continuous power supply and will operate normally.
In this mode, pushing the DRAIN TEST button will
have no effect.
Alarm Indication
The following conditions can cause the alarm indicator to
light:
• Compressor overload
• Low refrigerant suction pressure
• High refrigerant discharge pressure
• Low oil pressure (semi-hermetic compressors only)
A qualified refrigeration mechanic should identify and
correct the problem if an alarm condition occurs. In most
cases it will be necessary to firmly depress the
reset push-button located on the dual-pressure
switch, which is inside the electrical enclosure.
Follow all safety procedures applicable to electrical
equipment when opening the electrical enclosure. Refer to
the Installation, Operation, Start-Up, and Maintenance
Manual for more information.
Service Due Indication
“Service Due” indicates the dryer is due for routine
maintenance. Please read the maintenance section or
contact your Pneumatech dealer. In SERVICE DUE mode,
several functions relating to the accumulated run time can
be accessed. The accumulated run time can be viewed,
and the service due threshold (total accumulated run time
before SERVICE DUE indicator lights) can be viewed and
tested.
Drains will not operate normally in Service
Due mode. Drains will not receive power
in Service Due mode unless the DRAIN
TEST key is held down. Never operate the
unit in Service Due mode for an extended
period of time.

Pub. No. OM-A-75 REV. 4 — March 2006
9
To enter the SERVICE DUE mode (and view the
accumulated run time) press SELECT, UP ( ↑ ) and DOWN
( ↓ ) keys simultaneously. The display will show the
accumulated run time in tens of hours. If the display reads
50, for example, the accumulated run time is 500 hours.
1. To display the service due threshold, hit the DOWN
(
↓ ) arrow key. The service due indicator will light.
2. To test the service due timer function, push the
SELECT and UP (
↑ ) keys simultaneously. The
accumulated run time will temporarily be set to a
value that is 60 seconds less than the service due
threshold setting. If the service due timer is
functioning properly, the SERVICE DUE indicator will
flash after the 60 seconds has elapsed. After a few
seconds, SERVICE DUE mode will return to normal
operation. The indicator will stop flashing and the
accumulated run time will return to its previous value.
3. To reset the accumulated run time to zero, hold the
SELECT key for 5 seconds.
To exit SERVICE DUE mode, press the UP (
↑ ) and DOWN
( ↓ ) keys simultaneously. This can not be done while a
service due timer test is in progress.
SHUTDOWN PROCEDURE
1. Open the bypass valve to allow process flow to
continue downstream. Then close the outlet isolation
valve on the dryer bypass piping.
2. Close the inlet isolation valve on the dryer bypass
piping. At this time the dryer is isolated and can be
depressurized, ready for servicing.
3. Turn the power switch to the OFF position.
NOTE: The alarm indication light (red) signifies the
refrigerant compressor is not running. The reasons can be:
• Low suction pressure
• High discharge pressure
• Electrical problems
• Loss of refrigerant
• Dirty condenser
• Leaking evaporator, etc.
Refer to Troubleshooting Guide, Page 15, for problem
analysis and remedy. Call the factory if further assistance
is required.
OPERATING CONDITIONS
Entering Air Temperature
Units are designed for entering air temperature of 100°F.
If the temperature of entering air is to be greater than
100°F, the factory should be consulted to determine the
maximum possible air flow through the unit.
Entering Air Pressure
Standard units are designed for operating air pressure
100 PSIG (150 PSIG MAX.). Operating below 100 PSIG
will reduce system capacity.
Ambient Air Temperature
The allowable ambient temperature range is 40°F to
110°F. As temperatures approach freezing conditions,
frost or icing may develop in the unit. At temperatures
above 100°F, refrigeration capacity will decrease,
therefore affecting dew point.
Contact factory before authorizing any
warranty refrigeration service on the air
dryer. Identify the dryer by model and
serial numbers when calling factory.
The increased heat content or higher tem-
perature air requires the dryer to be over-
sized to prevent overloading of the
refrigerant compressor.

10 Pub. No. OM-A-75 REV. 4 — March 2006
MAINTENANCE
AIR DRYER MAINTENANCE
The dryer is factory tested before shipping. All controls are
calibrated for automatic operation. If the dryer is installed
in clean surroundings, within the temperature limits of the
specified ambient, the dryer will run trouble-free for a very
long time. Routine maintenance procedures recommended
are the following:
1. Checking the fan motor(s) for proper operation to
maintain the cooling air to be drawn through the
condenser and blown over the refrigerant
compressor. If the dryer is equipped with condenser
ambient filters, check, clean or replace as needed to
maintain the proper air flow through the condenser.
Dirty ambient filters will reduce the air flow through
the condenser, and trip the compressor “off” at the
overload control.
2. For dryers without ambient filters, clean the
condenser periodically to maintain the proper heat
transfer on the condenser coil. Dirty condenser will
raise the head pressure of the refrigeration system
and trip the compressor “off” at the overload control.
Running the compressor on high head pressures may
cause premature failures. Check the ambient
temperature limits to be maintained at the
installation.
3. Check and clean water-cooled condensers for dirt,
scale and sludge buildup every year or as needed.
Cooling tower water condensers may need cleaning
more often if the water is not properly treated.
4. Check the suction pressure gauge. Reading should
be within the specified range after a few minutes of
start-up. Suction pressure below the range will cause
freeze-up inside the air system, increasing the
pressure drop across the air dryer. Suction pressure
above the range will reduce the refrigeration cooling
capacity.
5. Check the pressure drop across the air dryer at full
capacity flow. If it is higher than specified value
(normally 5 PSI or less), consult factory. If pressure
drop increases over years of operation, it may be
due to particulate buildup from air compressor
intake. In that event, back-flush the dryer with any
MILD DETERGENT. See Figure 2.
To back-flush, disconnect air dryer, plug the drain line and
fill the air system with the detergent water solution. Hold it
for 4-6 hours. Circulate the detergent from air outlet to air
inlet with a pump. Flush the system with warm water. If
pressure-drop still exists, contact factory.
FIGURE 2 — BACK FLUSH FLOW DIAGRAM
AUTOMATIC DRAINS
The recommended settings for the drain time is determined
by the moisture load. The cycle time should be adjusted to
approximately 3 to 4 minutes. The drain time should be set
so the drain expels all of the liquid and then a short burst
of air.
Periodically check the automatic drains for proper
drainage. If the drains are not functioning, the condensed
moisture will be re-entrained downstream of the air dryer.
Float operated automatic drains need periodic cleaning
with soap and water to remove solids from the valve seat.
If the valve is stuck open, clean with soap and water and
then use compressed air to clean the valve seat. Electronic
solenoid operated drains may be manually tested
periodically for proper operation.
AIR OUTLET
AIR INLET
A/A HEAT EXCHANGER
A/R HEAT EXCHANGER
SEPARATOR
MILD DETERGENT
CIRCULATING
PUMP
PLUG

Pub. No. OM-A-75 REV. 4 — March 2006 11
Drain Valve Clean Up Procedure
A. Depressurize the drain valve.
B. Disconnect the power source.
C. Remove the valve from the compressed air system.
D. Remove the solenoid coil.
E. Remove the stainless steel sleeve from valve body.
F. Clean the valve body internals, and all other
components.
G. Replace diaphragm as needed. The valve rebuild kit
is available.
H. Assemble the valve parts.
I. Connect the solenoid coil.
J. Install the drain valve in the system.
FIGURE 3 — DRAIN VALVE
Recommended Operation and Maintenance for the
Particle Strainer
The particle strainer should be cleaned once every week
or as needed.
1. Close the shut-off valve on the particle strainer.
2. Depressurize the drain by pressing the drain PRESS
TO TEST or DRAIN TEST key.
3. Unscrew bottom of the particle strainer and clean the
screen.
FIGURE 4 — PARTICLE STAINER
SLEEVE
BODY ADAPTER
*O-RING
*PLUNGER
*SPRING
RETAINER
DIAPHRAGM
VALVE BODY
{
DIAPHRAGM
ASSEMBLY
Failure to depressurize may cause bodily
injury.
1/2" NPT INLET
3/8" NPT OUTLET
.75"
SHUT-OFF
VALVE
1.375"
SCREEN
REMOVABLE SCREEN

12 Pub. No. OM-A-75 REV. 4 — March 2006
COMPRESSOR
Refrigerant compressors normally do not need any
maintenance. The compressor will unload or adjust for
different load conditions with the refrigeration controls.
Any time power is applied to the compressor, and the
suction pressure is higher than the specified readings, the
compressor is either not pumping or failed electrically, or
tripped “off” at the overload protection. If the compressor
does not automatically reset within a few minutes, it
requires servicing. Service must be performed by a
qualified refrigeration technician.
EXPANSION VALVE
Air dryers equipped with an automatic expansion valve
are factory adjusted for proper cooling. The valve
adjusting stem is secured with a lock nut at the factory to
maintain proper setting. Larger units are equipped with a
thermostatic expansion valve, factory set to maintain a
superheat of 8 to 10°F. These valves do not need
adjustment in normal operation. Generally, superheat
adjustments are needed only at the time of valve
replacement. Expansion valve service must be performed
by a qualified refrigeration technician.
HOT GAS BYPASS VALVE
Model AD-10 and larger air dryers come equipped with
modulating hot gas bypass valves. This valve maintains
the refrigerant suction pressure in varying load conditions.
The dryer will run from no load to full load conditions
without freeze-up. The operation of this valve is automatic.
If the valve needs adjustment, turn the adjusting
stem clockwise to raise the suction pressure, and
counterclockwise to lower the suction pressure. This
adjustment should be made under a no-load condition if
possible. When the adjustment is made, turn one quarter
of a turn at a time, and wait 3 to 5 minutes between
adjustments. Once the adjustment is complete, secure the
adjusting stem with the locknut that is provided. Careful
adjustment of this valve is necessary for normal operation
of the air dryer. Hot gas bypass valve adjustment may be
made by maintenance personnel. (See Figure 5.)
FIGURE 5 — HOT GAS BYPASS VALVE ADJUSTMENTS
3/8" HEX.
ADJUSTMENT
*
5/16" ALLEN
WRENCH
ADJUSTMENT
*
3/16" ALLEN
WRENCH
ADJUSTMENT
*
*ADJUSTMENT POINT

Pub. No. OM-A-75 REV. 4 — March 2006 13
FIGURE 6 — FLOW DIAGRAM

14 Pub. No. OM-A-75 REV. 4 — March 2006
REFRIGERATED AIR DRYER SERVICE CHECKLIST
Please get answers to as many questions as you can before writing or calling for service.
1. Customer’s Name ____________________________________________________________________________________
Phone no. ____________________________________ Fax no. ____________________________________________
2. Model no.____________________________________ Serial no. ___________________________________________
Voltage L1 ___________ L2 _________________ L3 _______________ PH ______________ HZ ______________
Amp draw L1 ___________________________ L2_______________________ L3 __________________________
Actual air flow (SCFM)_________________________ HP _________________________________________________
3. Description of problem
____________________________________________________________________________________________________
____________________________________________________________________________________________________
____________________________________________________________________________________________________
____________________________________________________________________________________________________
____________________________________________________________________________________________________
____________________________________________________________________________________________________
____________________________________________________________________________________________________
____________________________________________________________________________________________________
4. Air in temperature (°F) ________________________________________________________________________________
5. Air out temperature (°F) _______________________________________________________________________________
6. Air in pressure (PSIG) _________________________________________________________________________________
7. Air out pressure (PSIG) ________________________________________________________________________________
8. Refrigerant suction pressure when unit is operating (PSIG) __________________________________________________
9. Refrigerant suction pressure when unit is not operating (PSIG)_______________________________________________
10. Refrigerant discharge pressure when unit is operating (PSIG) _______________________________________________
11. Inspect refrigerant suction line at the outlet of air to refrigerant heat exchanger:
Cold ______________________ Hot ___________________ Temperature (°F)_________________________________
12. Inspect refrigerant suction line at inlet of compressor: Temperature (°F) _______________________________________
13. Oil pressure when unit is operating (PSIG) _______________________________________________________________
14. Separator skin temperature (°F)_________________________________________________________________________
15. Location of unit Indoor_________________________ Outdoor_________________________________________
Clean _________________________ Dusty ___________________________________________
16. Ambient temperature (°F) ________________ Air-cooled condenser clean? Yes ________________ No ___________
17. a. Water-cooled condenser: City ____________________________ Tower_____________________________________
b. Inlet water temperature (°F)_____________________ Outlet water temperature (°F) _________________________
c. Inlet water pressure (PSIG) ___________________Outlet water pressure (PSIG)_______________________________
18. Inspect auto drain, operation: Stuck open ____________________ Stuck closed _____________________________
NOTE: Maintenance Personnel, Copy This Page, Fill In Form and Fax to 262-658-1945

Pub. No. OM-A-75 REV. 4 — March 2006 15
TROUBLESHOOTING
The following conditions can cause abnormal operation or malfunction of the air dryer
• High inlet air temperatures
• High cooling water inlet temperatures
• Untreated cooling water
• Dirty condenser
• Low ambient temperatures
• Malfunctioning automatic drains at aftercooler, or
dryer
• Refrigerant overcharge
• Leaky evaporator
• Electrical power supply more than ±10% of the rated
voltage
• Low inlet air pressures
• Contaminated cooling water
• Condenser water pressure below 35 PSIG
• High ambient temperatures
• Compressed air flow greater than rated capacity
• Undersized fuses
• Refrigerant undercharge
• Clogged air compressor air intake filter
If any of these symptoms are noticed, refer to
Troubleshooting Guide.
Table 1 — Troubleshooting Guide
Symptoms Cause Remedy
A. Unit does not run. 1. Motor line open.
2. Fuse blown.
3. Tripped overload.
4. Safety controls open.
5. Air switch open. (Dead end
control)
6. Frozen (locked) compressor.
7. Wiring improper or loose.
1. Close disconnect switch, to start.
2. Replace fuse.
3. Turn switch off, wait 15 minutes,
check for overload condition.
4. Repair or replace.
5. Check air pressure. Adjust air
and/or switch. If defective repair
or replace.
6. Repair or replace.
7. Check wiring against diagram.
B. Unit short cycles. 1. Motor compressor overload
cutting out.
2. Shortage of refrigerant.
3. Suction pressure low.
4. Sticking expansion valve.
1. Check for high head pressure,
clogged condenser, high ambient,
or air overload. Check high
pressure cutout, repair or replace.
2. Repair leak and recharge.
3. Check hot gas bypass adjust,
repair or replace.
4. Repair or replace.
C. Compressor will not start – hums. 1. Improperly wired.
2. Low line voltage.
3. Starting capacitor defective.
4. Relay or contactor not closing.
5. Start winding open.
6. Single-phasing.
1. Check wiring against diagram.
2. Check voltage – correct.
3. Replace.
4. Check for reason – repair or
replace.
5. Check leads, if leads OK replace
motor.
6. Check fuses.

16 Pub. No. OM-A-75 REV. 4 — March 2006
D. Compressor starts and runs – short
cycles on overload.
1. Low voltage, or phase unbalance.
2. Additional current going thru
overload.
3. Overload protectors defective.
4. Run capacitor weak.
5. High discharge pressure.
6. Short in winding.
7. Current relay sticking.
1. Check voltage to be within ±10%
of voltage listed on name plate.
2. Check wiring diagram, check for
added electrical devices
connected thru protector.
3. Check current, replace.
4. Check capacitance, replace.
5. Refer to G 1-8.
6. Check resistance, replace
compressor.
7. Check floor level, tap & release.
E. Relay burned out. 1. Low or high line voltage.
2. Incorrect running capacitor.
3. Short cycling.
4. Wrong relay.
5. Incorrect mounting.
1. Check voltage to be within ±10%
of voltage listed on name plate.
2. Replace with proper capacitance.
3. Refer to B and C.
4. Replace with proper relay.
5. Mount in correct, rigid position.
F. Capacitors burn out. 1. Improper capacitor.
2. High line voltage.
1. Replace with proper capacitor.
2. Lower voltage to not more than
10% above rating.
G. Head pressure too high. 1. Refrigerant overcharge.
2. Air in system.
3. Dirty condenser.
4. Location too hot.
5. Defective condenser pressure
switch.
6. Defective fan motor.
7. Fan operating in wrong direction.
8. Defective water regulating valve.
1. Purge or vacuum and recharge.
2. Check for reason, repair.
3. Blow clean with compressed air.
4. Cool ambient, relocate unit, add
ventilation.
5. Repair or replace.
6. Replace.
7. Switch two wires at disconnect.
8. Adjust, repair or replace.
H. Head pressure too low. 1. Refrigerant shortage.
2. Compressor suction or discharge
valves inefficient.
3. Defective condenser pressure
switch.
4. Defective water regulating valve.
1. Repair leak and recharge.
2. Repair or replace.
3. Repair or replace.
4. Adjust, repair or replace.
J. Noisy unit. 1. Mountings loose.
2. Bent fan blade.
3. Fan motor bearing worn.
4. Refrigerant flooding back.
5. Compressor oil charge low.
1. Tighten mounting, etc.
2. Straighten or replace blade.
3. Replace.
4. Check expansion valve, adjust,
repair or replace. Check
crankcase heater.
5. Check oil level.
K. Frosted liquid line. 1. High side service valve partially
closed or restricted.
2. Restricted filter/dryer.
1. Open valve or remove restriction.
2. Replace.
L. Frosted suction line. 1. Expansion valve and/or hot gas
bypass out of adjustment.
1. Adjust the hot gas bypass valve to
bring the suction pressure into the
proper range.
Table 1 — Troubleshooting Guide, continued
Symptoms Cause Remedy

Pub. No. OM-A-75 REV. 4 — March 2006 17
M. Top condenser coils cool when unit
in operation.
1. Refrigerant shortage.
2. Compressor inefficient.
1. Repair leak and recharge.
2. Repair or replace.
N. Unit runs but air temperature is
high.
NOTE: Outlet air temperature gauge
may read higher than actual
temperatures at low air flow conditions.
1. Refrigerant leak.
2. Evaporator controls set too high.
3. Filter/dryer clogged.
4. Refrigerant shortage.
5. Dirty condenser.
6. Air in system.
7. Compressor inefficient.
8. Evaporator control(s) stuck.
9. Defective insulation.
10. Air overload.
11. Unit too small.
12. High ambient.
13. Entering air temperature too high.
1. Locate with leak detector. Repair
or replace defective part.
2. Refer to L – above.
3. Replace.
4. Repair leak and recharge.
5. Clean condenser.
6. Check reason, repair, vacuum,
recharge.
7. Repair or replace.
8. Repair as required, adjust.
9. Repair.
10. Reduce load.
11. Add unit or replace.
12. Reduce or change location.
13. Lower entering air temperature.
P. Unit runs but low air pressure. 1. System pressure low.
2. Precooler and/or evaporator
clogged.
3. Incorrect piping.
4. Air overload.
5. Unit too small.
6. Excess water in unit.
7. Evaporator freeze-up.
8. Clogged air compressor intake
filter.
9. Dirty air system.
1. Increase pressure.
2. Back-flush using mild detergent,
Figure 2 on Page 10.
3. Increase line size and/or correct
piping as required.
4. Reduce overload.
5. Add another unit or replace with
larger unit.
6. Check drain, repair or replace if
needed.
7. Adjust hot gas bypass valve.
8. Clean or replace air intake filter.
9. Back-flush as described in
Figure 2 on Page 10.
Q. Unit runs, but air flow erratic or
zero.
1. Freeze-up.
2. Precooler and/or evaporator
clogged.
3. Restriction in piping upstream
from unit.
1. Check suction temperature at
evaporator outlet or turn off unit
and allow it to thaw to determine
if this is problem. Adjust controls
at no-load if freezing is occurring.
2. Refer to P-2 above.
3. Correct as required.
R. Evaporator freeze-up. 1. Hot gas bypass valve out of
adjustment.
1. Adjust suction pressure. Adjust hot
gas bypass valve.
S. Condenser fan blows outward. 1. Improper wiring at disconnect
(3-phase only)
1. Reverse two wires.
Table 1 — Troubleshooting Guide, continued
Symptoms Cause Remedy

LIMITED WARRANTY
Warranties and Limitation of Liability : Pneumatech (“the Company”) warrants that it will, in its sole
discretion, either repair or replace Products and/or Components of Products sold by it which have defects in
material or workmanship (covering Components and reasonable labor) provided: (a) Customer notified the
Company of any claim of defect in material or workmanship within fourteen (14) months from date of shipment
from the Company’s factory or twelve (12) months from the date of initial operation of Product, whichever occurs
first; (b) Customer holds the Product or Component for inspection by the Company’s representative; (c) Customer
returns the Product(s) or Component(s) only with Company authorization, within forty-five (45) days after such
authorization, with transportation charges prepaid and shipped pursuant to the Company’s directions; and (d) the
Product(s) or Component(s) are found defective in materials or workmanship upon examination by the Company.
Products or Components shall not be considered defective if they substantially fulfill performance requirements set
forth in the Company literature and are manufactured in accordance with the Company’s specifications or
government specifications when applicable. Replacement / spare Components will be warranted for six (6)
months from the date of shipment from the Company’s factory, or for the balance of the original warranty period
(or extended warranty period, if registered, see below), whichever is longer.
Available Extended Warranty: In addition to the above warranty, if the Customer registers the warranty of a
standard price book Pneumatech dryer or a standard price book ConservAIR Intermediate Control
®
(“Specified
Products”) via the internet at www.pneumatech.com or www.conservair.com : (i) the above warranty will
be extended to twenty-four (24) months from the date of shipment from the Company’s factory (covering
Components and reasonable labor) as to such Specified Products and (ii) the Company warrants that it will, in its
sole discretion, either repair or replace heat exchangers on refrigerated dryers and valves on PH, PE, PB or PHC
style regenerative dryers and valves on Intermediate Controls
®
for defects in material or workmanship (covering
Components only) provided: (a) Customer notified the Company of any claim of defect in material or
workmanship within sixty (60) months from date of shipment from the Company’s factory; (b) Customer holds the
Product or Component for inspection by the Company’s representative; (c) Customer returns the Component(s) only
with Company authorization, within forty-five (45) days after such authorization, with transportation charges
prepaid and shipped pursuant to the Company’s directions; and (d) the Component(s) are found defective in
materials or workmanship upon examination by the Company. Components shall not be considered defective if
they substantially fulfill performance requirements set forth in the Company literature and are manufactured in
accordance with the Company’s specifications or government specifications when applicable. These extended
heat exchanger and valve warranties cover only parts, not labor, and are not pro-rated in any way.
The warranties stated herein will not extend to Products or Components that: (a) have been subject to misuse,
neglect, accident, or that have been repaired or altered by, or at the direction of Customer, without the Company’s
written authorization, or (b) have not been maintained or installed by Customer pursuant to the Company’s
guidelines. The Company shall not be liable for any expense, liability or loss incurred by Customer nor for any
special, consequential, liquidated or other damage or penalties suffered by Customer or anyone else with respect
to any Product or Component.
There are no warranties which extend beyond the warranties stated herein. The
foregoing warranty is in lieu of all other warranties whether expressed, implied or
statutory, including implied warranties of merchantability or fitness for any
particular purpose. No representation or warranty of any person on behalf of the
Company shall extend the liability or responsibility of the Company beyond the
terms of the warranties stated herein. In no event shall the Company be liable for
any loss of profits, loss of use, incidental, consequential or special damages to any
person or company resulting from the use of the Company Products.
Pneumatech Inc.
4909 70th Avenue
Kenosha, WI 53144
Phone: [phone]
Fax: [phone]
www.pneumatech.com