User & Technical Manual
RZ-01A & RZ-01V Series
Rev 1.6
Title: RZ-01A & RZ-01V Air Conditioner User & Technical Manual
Department: Engineering
Objective: To provide important information for maintenance, diagnostics and advance operations of the
DELTA-T RZ-01A & RZ-01V Series Air Conditioners.
Revision History:
Rev
Date
Owner
Description of Changes
1.4
1.5
1.6
01-16-13
02-05-13
02-21-13
B. Slotnick
B. Slotnick
B. Slotnick
New Format Initial Release
Removed heater option reference
Corrected series identification
Statement of Confidentiality
The Manual and other materials contain proprietary information, comprising ISC Inc.'s trade secrets. Please
maintain the confidentiality of all proprietary information during and after the term of the use agreement. Also,
please refrain from using this proprietary information in any other manner, including in any other business,
without ISC Inc.’s written approval.
ISC Inc. reserves the right to revise and otherwise modify the Manual to reflect changes in the requirements,
standards, and operating recommendations. The Manual is the sole property of ISC Inc. It must be returned
upon the expiration or the termination of the term of use agreement.
By accepting the Manual you have read and understand the Statement of Confidentiality and will abide by its
terms and conditions.
4421 Tradition Trail ● Plano, Texas 75093 ● 972 -964-2700 ● 800-836-7472
URL: www.iscenclosurecooling.com ● Email: iscinfo@iscsales.com
SP-ENG-210-100-09 Rev 1.6
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TABLE OF CONTENTS
Overview
4
Inspecting the Equipment
4
Unpacking the Air Conditioner
4
Moving the Air Conditioner
5
Unit Label
5
Operation
6
Preliminary Testing
6
Mounting the Air Conditioner
7
Unit Specifications
8
Options
10
System Faults
13
Digital Temperature Controller Programming
13
Preventative Maintenance
16
Field Serviceable Parts
17
Safety Information
17
Troubleshooting Guide
18
Physical Dimensions
21
Electrical Schematic
23
Warranty Information
24
Return Material Authorization (RMA) Procedure
25
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SP-ENG-210-100-09 Rev 1.6
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Overview
Thank you for your purchase of the DELTA-T Special Purpose Air Conditioner. Our air conditioning
equipment is carefully designed to cool and dehumidify the air in electronic component enclosures.
ISC has designed air conditioners for all types of electronic equipment enclosures providing capacity
from 1,000 to 24,000 BTUH.
This manual will guide you through the installation, maintenance, diagnostics and advance operations
of the RZ-01A & RZ-01V Series Air Conditioners. This manual contains important information for the
end-user who installs, maintains and/or operates the RZ-01A & RZ-01V Air Conditioner.
Technical Support
By Phone: 972-964-2700 / 800-836-7472
(Monday – Friday, 7:30 am – 5:00 pm Central Time)
By Email: iscinfo@iscsales.com
Our goal is to have continuous improvement for both our equipment and our documentation. We rely
and appreciate your feedback to help us achieve our goal. Our technical support team is glad to work
with you if you require additional technical information not provided in this manual.
Inspecting the Equipment
DELTA-T air conditioning equipment is designed, manufactured and packed to prevent damage from
normal handling, shock and vibration during shipment. It is necessary to inspect your equipment upon
receipt to insure that there is no visual or hidden damage.
Upon receipt of the equipment, insure that it is always top side up as indicated by “THIS SIDE UP”
labels. This insures that the compressor oil is not displaced.
Note: If the equipment has been on its side it must be put upright for at least 24 hours before installing
or running to insure the compressor oil has returned to the compressor.
All physical damage to packing or signs of damage to the equipment must be noted on the freight bill
of lading. Packages must be opened after receipt and inspected for any internal or concealed damage
to the equipment and to verify proper count and order fulfillment. Delivery of without the pallet, not top
side up, other freight on top, damaged or wet should be refused.
Unpacking the Air Conditioner
Always keep air conditioner top up as shown by the packaging label and arrows. If the unit is to be
transported after initial unpacking, place air conditioner back in original packing to prevent damage.
For shipment by UPS or freight carrier, repack as received and re-band to the pallet.
Note: Shipping without being strapped to the pallet may result in tipping and damage, this will void the
warranty.
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SP-ENG-210-100-09 Rev 1.6
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Moving the Air Conditioners
Read this section completely before running or installing your DELTA-T air conditioning equipment.
Note: You will need to perform a Preliminary Test before mounting the air conditioner. Refer to the
Preliminary Test section in this manual for instructions on how to run this test. You will also need to
prepare the enclosure that is to be cooled for mounting in accordance with this manual and the
template supplied.
Note: DELTA-T air conditioning equipment must be mounted vertically with a minimum of 3” air space
for condenser air return and supply. If necessary, equipment may be mounted at up to a 5 degree
angle (rotary compressors) without damaging the compressor.
If air conditioner is to be shipped or transported at any time; pack in original packaging and strap to
pallet to prevent damage. Air conditioner must be kept upright at all times. Air conditioners are not
designed to be shipped attached to an equipment enclosure. Air conditioners shipped which have
internal damage due to shipping while attached to enclosures are warranty voided.
Unit Label
Each air conditioner has a unit label, be sure to record the data from the label to the template below
and keep this information in a safe place for warranty and ordering parts. To prevent damage to
equipment, electrical panel and wiring, and to prevent personal injury, assure that the power source is
compatible with the equipment before operating. When recharging, refrigeration type and amount
must be the same as shown on the unit label or air conditioner will not operate properly or may be
damaged and may result in the warranty voided and UL listing voided.
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SP-ENG-210-100-09 Rev 1.6
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Operation
DELTA-T air conditioners will lower (or increase as necessary) the temperature inside an enclosure to
ensure its proper operational temperature. Our air conditioners, when sized properly, will provide
cooling or heating automatically controlled by the temperature digital controller.
DELTA-T air conditioners operate as a “closed loop” system with no exposure or introduction of
outside air. This insures that the enclosure is separated from and is not contaminated with ambient
air, dirt, chemicals, dust, moisture or foreign matter so that sensitive enclosure components are
protected and are kept at your required operational temperature.
An air conditioner is designed to dehumidify and extract heat from an area, or provide heat to an area.
The cooling is done using a simple refrigeration cycle. A product of this simple refrigeration cycle is
excess humidity that condenses to a liquid.
DELTA-T air conditioners are designed using an advanced refrigeration cycle and are equipped with a
Condensate Removal System that changes the excess humidity liquid into a vapor which is then
vented to the atmosphere. In the event of excess water vapor where the enclosure door has been left
open there is an overflow hole on the bottom of every unit. Please contact ISC Inc. if you encounter
excess water coming from your air conditioner.
Preliminary Testing
Before mounting the air conditioner to the enclosure, test for proper operation. Follow the steps below
prior to installation.
WARNINGS
The air conditioner must sit upright for 24 hours to assure the compressor oil has drained down to the
compressor. Check the unit label to assure the electric power available to the air conditioner is the
proper voltage and phase. Check the electric power source for proper ground wire and neutral wire
installation per 2008 NEC. Assure that the electric power is protected by a circuit protection device;
refer to the Unit Specification section in this manual for proper circuit protection sizing.

Plug the unit’s power cord into your source to start the evaporator fan and, if desired, change
the set point. Refer to Digital Temperature Controller Programming section on this manual for
details on changing the set point. Factory default settings should be satisfactory; however you
may want to adjust heat, cooling and alarm set points for your specific application.

The condenser fan is controlled by the refrigerant high heat pressure and will turn on later
when the operating pressure builds up. This feature allows low ambient operation and
reduces current inrush at initial power on.
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SP-ENG-210-100-09 Rev 1.6
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



Run the air conditioner for 15 minutes; during this time the condenser fan will turn on after the
condenser coil warms up. Note: Ambient Temperature must be at least 75°F.
Turn the unit off if the equipment makes any unexpected or hard mechanical noises or
vibrations and refer to the troubleshooting guide in this manual.
The supply cold air should be at least 10°F colder than the return air entering the unit. If it is
not, refer to the troubleshooting guide in this manual;
When you are satisfied that the unit is operating properly, turn unit off, disconnect the power
and mount the unit on the enclosure in accordance with the Mounting the Air Conditioner
section in this manual.
Mounting the Air Conditioner
Using the template supplied, determine where the air conditioner is to be mounted and assure that all
required cuts and holes will not interfere with or damage the enclosure or its contents. Assure that
there is a 3” clearance between walls / obstructions and the air conditioner for the condenser supply
air and return air flow so that it is not restricted. Restricted condenser air flow will affect the air
conditioner’s performance. Mount the air conditioner high on the enclosure in order to cool the hot air
in the top of the enclosure. Position the unit where the cold air can circulate across the width of the
enclosure to cool it all the way across.
Once proper mounting placement is determined, turn the enclosure equipment off, if possible, to
prevent damage. Drill and cut the holes as indicated on the mounting template. Install insulation
gasket as required to insure an air tight closed loop seal. Be cautious not to let any cutting debris fall
into the enclosure. Attach the hanging bolts as indicated on the template to hold the unit onto the
enclosure and then use the mounting screws that are provided.
Hang the air conditioner on the hanging bolts and from inside the enclosure use the fasteners supplied
to attach the air conditioner to the enclosure. Insure that these fasteners are tight in order to prevent
the unit from falling off the enclosure. These fasteners should be checked periodically to insure that
they have not become loose due to vibration.
Ensure that the power supplied is compatible with the air conditioner’s power requirements. Properly
attach the unit’s power cord to a circuit that meets the equipment requirements and provide a circuit
protection device based on the Unit Specifications section of this manual.
After mounting the air conditioner, replace/close the enclosure door and start air conditioner; test for
air leaks to assure a proper closed air loop seal and run test the unit to assure proper operation after
mounting. If any cold air leaks are found, check for proper mounting and apply silicone-free Lexel seal
if leaks persist. Assure that the air conditioner’s condenser inlet air filter is installed properly and
cleaned regularly.
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SP-ENG-210-100-09 Rev 1.6
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CAUTION
If mounting the air conditioner to the enclosure door, confirm with the enclosure manufacturer that the
door’s hinges will support the air conditioner’s added weight (see equipment specifications). Insure
that when the door is fully open that the enclosure will not topple over due to the off-center load.
Unit Specifications
The following tables provide electrical and refrigeration specifications for the RZ-01 Series Air
Conditioners.
RZ-01A Series
Nominal Capacity Rating: 1,000 BTUH
Standard Maximum Ambient: 125°F
Unit Weight: 57lbs (120/230VAC)
Operating
Voltage
Range
Inrush
Current
(Start
Up
Current)
Loading
Current
(Running
Current)
SCCR
(Short
Circuit
Current
Rating)
Recommended
Fuse Selection
KVA Rating
(Volts)
(Amps)
(Amps)
(Amps)
(K-Watts)
RZ-01A -126
110-120
22.69
3.44
*2
RZ-01A -236
220-240
13.77
2.67
*2
(Amps)
12 Amp Class
CC, CCMR
Time Delay *
7 Amp Class
CC, CCMR
Time Delay *
Model
Refrigerant
Type
Refrigerant
Amount
Low/High
Unit
Pressures
(ounces)
(psi)
0.5
R134a
12.00
88 / 178
0.6
R134a
12.00
88 / 290
* Time-delay Fuses with the following electrical characteristics are recommended. Fast -acting fuses
are not recommended.
% of Ampere Rating
110 %
125 %
200 %
Opening Time
15min Minimum
1hr Maximum
12sec Minimum
4min Maximum
*2 SCCR rating is based on the SCCR rating for the circuit protection device installed in the panel /
enclosure per UL50 & UL508a to protect the AC unit. Typically 100KA – 200KA for Time-Delay Fuses.
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SP-ENG-210-100-09 Rev 1.6
8 | Page
RZ-01V Series
Nominal Capacity Rating: 1,500 BTUH
Standard Maximum Ambient: 125°F
Unit Weight: 57lbs (120/230VAC)
Operating
Voltage
Range
Inrush
Current
(Start
Up
Current)
Loading
Current
(Running
Current)
SCCR
(Short
Circuit
Current
Rating)
Recommended
Fuse Selection
KVA Rating
(Volts)
(Amps)
(Amps)
(Amps)
(K-Watts)
RZ-01V-126
110-120
22.69
3.89
*2
RZ-01V-236
220-240
13.77
2.67
*2
(Amps)
12 Amp Class
CC, CCMR
Time Delay *
7 Amp Class
CC, CCMR
Time Delay *
Model
Refrigerant
Type
Refrigerant
Amount
Low/High
Unit
Pressures
(ounces)
(psi)
0.5
R134a
12.00
88 / 178
0.6
R134a
12.00
88 / 290
* Time-delay Fuses with the following electrical characteristics are recommended. Fast -acting fuses
are not recommended.
% of Ampere Rating
110 %
125 %
200 %
Opening Time
15min Minimum
1hr Maximum
12sec Minimum
4min Maximum
*2 SCCR rating is based on the SCCR rating for the circuit protection device installed in the panel /
enclosure per UL50 & UL508a to protect the AC unit. Typically 100KA – 200KA for Time-Delay Fuses.
4421 Tradition Trail ● Plano, Texas 75093 ● 972 -964-2700 ● 800-836-7472
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SP-ENG-210-100-09 Rev 1.6
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Options
The RZ-01A & RZ-01V Series Air Conditioners may be ordered with the following options. Review the
list below for the specifications and functions of the option(s) that apply to your unit.
Low Ambient
This option consists of circuitry to protect the compressor in a low ambient temperature environment.
The low ambient package is designed to provide an optimum constant low current in the compressor
motor during the non cooling state. This option provides internal heat to the compressor to protect it
from stalls and hard starts during long periods of compressor off state.
Dry Contact
This option provides an early warning capability to your enclosure to aid in the protection of your
expensive equipment. The Dry Contact is programmed with an individual dry contact set point to
monitor the enclosure temperature limit that you require. When the enclosure temperature has
exceeded the maximum limit, the Form C gold plated contact will activate to notify you that there is a
problem in achieving your cooling set point.
Default Settings:



105°F Dry Contact High Temperature Alarm Set Point
2°F Recovery Differential
3min Temperature Alarm Delay
At the default settings the Dry Contact initial conditions are normally open and/or normally closed.
When the unit is powered on and the temperature exceeds 105°F for a period longer than 3 minutes
the Dry Contact will activate. At this time the normally open contact will close and the normally closed
contact will open. This state will remain until the temperature has decreased to 103°F.
Note: The dry contact is not a power status indicator, rather a high temperature alarm alerting you that
the unit is unable to meet the cooling set point.
Refer to Advanced Digital Temperature Controller Programming section on page 8 for details on
changing these parameters.
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Celsius Programming
Celsius Programming option allows the user to control the DELTA-T Air Conditioner in SI units. This
feature can be programmed into the digital temperature controller at time of manufacturing. This
feature is also available as an upgrade to air conditioners already in the field equipped with Gen 2.0
controller via a flash drive key.
External Heat Output
This option allows you to add an external heater to be located anywhere in your enclosure. These
external heaters are ideal for focusing on individual sections of the enclosure without having a large
capacity Built-in Heater.
External Heater capacities available are 100 Watt, 150 Watt, 200 Watt, 250 Watt, 300 Watt,
400 Watt, 550 Watt, 650 Watt & 950 Watt
Default Settings:


55°F Heat Set Point
3°F Differential
At the default settings the heater output turns on at 52°F and operates until the temperature has
reached 55°F. Refer to Advanced Digital Temperature Controller Programming section on this manual
for details on changing these parameters.
Special Programming
All DELTA-T Air Conditioners have a Special Programming option for selecting unique pre in
programmed settings for special requirements. Although most parameters are accessible in our digital
controller, this option allows you to receive a unit preset to your requirements without the need to
manually configure the unit. Refer to Advanced Digital Temperature Controller Programming section
for details on all default settings.
High Ambient
Most of our air conditioners have capabilities for high ambient application upgrades from our Standard
Maximum Ambient temperature of 125°F. With this option we can optimize the Air Conditioner during
manufacturing to achieve improved performance at high ambient conditions.
Open Door Kill Switch
This option provides you with an adjustable and mountable safety switch for your electronics
enclosure. This switch will disable power to the air conditioner when your electronics enclosure door is
open allowing you to work on your enclosure without the risk of unintentionally powering the unit.
Adjustable Temperature Probe
The adjustable temperature probe provides you with a 5’ temperature probe that can be installed
anywhere in your enclosure. This allows you to have the flexibility to monitor and maintain the
temperature at any specific location of your enclosure.
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Ethernet/IP Controller Output
This option provides the ability to communicate with the DELTA-T Air Conditioner controller via the
Ethernet/IP protocol. You can monitor and control all settings from a remote location with a PLC.
Full specifications will be provided with this option. For full details refer to the Ethernet/IP Option
Specifications included with the Air Conditioner.
Outdoor Option
When having our Programmable Digital Controller on the face of our Air Conditioner does not fit your
application, ISC offers the OD Package (i.e. Outdoor Option). This option moves the controller into
your enclosure using a 10’ cable along with a universal, 16 gauge powder coated steel mounting
bracket. The Air Conditioner will have no openings on the face of the unit. Below is partial schematic
showing the OD option wiring connections to the digital controller.
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System Faults
If any of the critical control parameters exceed limits, the compressor is turned off and an alarm
condition is indicated on the front panel.
There are three main conditions that can shut the AC compressor down:
 The condenser high temperature alarm
 The evaporator coil alarm
 The compressor thermal overload
In the event that the condenser coil overheats, a condenser high temperature alarm, HA2, will flash on
the display of the digital temperature controller and the compressor will turn off after a 3 minute time
delay.
In the case that the evaporator coil ices up or there is a leak, an evaporator coil alarm, CA, will flash
on the display of the digital temperature controller and the compressor will turn off after a 2 minute
time delay.
A thermal overload protects the compressor against faults. In the event that the snowflake status LED
is not flashing on the display and the compressor is not running, an internal fault may have occurred
on the unit. Refer to the Troubleshooting Guide in this manual.
Digital Temperature Controller Programming
For the end user this section will provide all the necessary information to view and change all functions
and parameters available to you.
HOW TO SEE THE SETPOINT……..
1.
2.
Press and immediately release the SET key. The display will show the setpoint value.
Press and immediately release the SET key or wait for 15 seconds to display the enclosure temperature
again.
HOW TO CHANGE THE SETPOINT……..
1. Press the SET key for more than 2 seconds to change the setpoint value.
2. The value of the setpoint will be displayed and the “F” LED starts blinking.
3. To change the SET value, press the UP or DOWN arrow key within 15 seconds.
4. To store the new setpoint value, press the SET key again or wait 15 seconds.
Note: The set value is stored even when the procedure is exited by waiting for the time -out to expire.
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HOW TO ACCESS HIDDEN MENU 1……..
1.
Enter the Programming mode by pressing the SET + DOWN arrow keys simultaneously for 3 seconds.
The “F” LED starts blinking.
2. Select the required parameter by pressing the UP or DOWN arrow key. Press the SET key to display
its value.
3. Use the UP or DOWN arrow key to change its value.
4. Press SET to store the new value and move to the following parameter.
To exit: Press SET + UP arrow keys or wait 15 seconds without pressing a key.
Note: The set value is stored even when the procedure is exited by waiting for the time -out to expire.
HOW TO ACCESS HIDDEN MENU 2……..
1.
Enter the Programming mode by pressing the SET + DOWN arrow keys simultaneously for 3 seconds.
The “F” LED starts blinking.
2. Release the keys, then push the SET + DOWN arrows keys simultaneously, again for more than 7
seconds.
The Pr2 label will be displayed immediately followed by the HY parameter.
3. Select the required parameter by pressing the UP or DOWN arrow key. Press the SET key to display
its value.
4. Use the UP or DOWN arrow key to change its value.
5. Press SET to store the new value and move to the following parameter.
To exit: Press SET + UP arrow keys or wait 15 seconds without pressing a key.
Note: The set value is stored even when the procedure is exited by waiting for the time -out to expire.
HOW TO LOCK THE KEYPAD……..
1.
2.
3.
Press and hold the UP and DOWN arrow keys simultaneously for more than 3 seco nds.
The POF message will be displayed and the keyboard will be locked.
At this point, it will be possible only to see the setpoint or the MAX or MIN temperature stored.
If a key is pressed for more than 3 seconds the POF message will be displayed.
HOW TO UNLOCK THE KEYPAD……..
1.
Press and hold the UP + DOWN arrow keys simultaneously for more than 3 seconds until the Pon
message is displayed.
Functions and Parameters
Function
Operation
Parameter
Menu
Location
Factory
Default
Operating
Range
Unit
Cooling Setpoint
Set Desired Cooling
Temperature
SET
Main
90
70 - 95
°F
Cooling
Differential
Control Hysteresis
Hy
Hidden
Menu 1
5
1 - 45
°F
Compressor
Protection
Anti short-cycle delay
AC
Hidden
Menu 2
5
0 - 50
min
Lod
Hidden
Menu 2
P1
P1 / P2
N/A
SAA
Hidden
Menu 2
105 / 55
-67 - 302
°F
Select Display Probe
Probed Displayed
P1 – Enclosure Temperature
P2 – Condenser Temperature
Auxiliary
Setpoint
Setpoint for Dry Contact
/ Heater
*1
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SP-ENG-210-100-09 Rev 1.6
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Function
Operation
Parameter
Menu
Location
Factory
Default
Operating
Range
Unit
Auxiliary
Differential
Heater or Dry Contact
Hysteresis *1
Shy
Hidden
Menu 2
3
1 - 45
°F
Maximum
Temperature
Alarm
Minimum
Temperature
Alarm
Alerts with “HA” when
maximum temperature has
been exceeded
Alerts with “LA” when
minimum temperature has
been exceeded
ALU
Hidden
Menu 2
105
45 - 302
°F
ALL
Hidden
Menu 2
45
-67 - 105
°F
*1 Note: When both Heater and Dry Contact options are included, these parameters only control Heater
Settings. Dry Contact is controlled by ALU.
Alarms Signals
Message
Cause
Outputs
Start and stop of the compressor after 15 minute
intervals *2
“P1”
Enclosure Probe Failure
“P2”
Condenser Probe Failure
No Output
*2
“HA”
Maximum Temperature Alarm: P1 > 105°F for 3
minutes (after initial 30 min. start up delay)
No Output
*2
“LA”
Minimum Temperature Alarm: P1 < 45°F for 3
minutes (after initial 30 min. start up delay)
No Output
*2
“HA2”
Condenser High Temperature Alarm: P2 > 145 °F for
3 minutes
Compressor Off
“LA2”
Condenser Low Temperature Alarm: P2 < 50 °F for 3
minutes
No Output
“CA”
Evaporator Coil Alarm: Low Pressure for 2 minutes
Compressor Off
“noP”
Invalid Probe Selected: Low Evaporator Coil
*2
*2
*2
No Output, Display Only
*2 Note: When both Heater and Dry Contact options are included, Dry Contact (Alar m Contact) Relay is
activated.
ALARM RECOVERY……..
If the compressor is turned off due to an alarm, it will be able to restart after the AC anti short-cycle time delay.
(Parameter AC = 5minutes)
Probe alarm P1 is cleared with no time delay after the fault is cleared.
Probe alarm P2 starts and stops with no time delay.
Temperature alarm HA automatically clears as soon as the temperature returns to below 105°F (the ALU setpoint) -2°F = 103°F.
Temperature alarm LA automatically clears as soon as the temperature returns to above 55°F (the ALL setpoint) +2°F = 47°F.
Temperature alarm HA2 automatically clears as soon as the condenser coils temperature returns to below 135°F.
Temperature alarm LA2 automatically clears as soon as the condenser coils temperature returns to above 60°F.
Temperature alarm CA automatically clears as soon as the pressure returns to normal.
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Preventative Maintenance
Air conditioners require regular cleaning of the condenser air inlet filter. Wash filter often if washable
using proper cleaning compound and back flushing the dirt out, or replace if not washable whenever it
appears physically dirty. Restriction to the flow of air over the condenser coil will degrade the
performance of the equipment, cause it to overheat, reduce cooling and can damage the compressor.
The overload switch in the compressor may cause the compressor to cycle if the condensing coil
pressure becomes too high due to air restriction. A further safety feature is the refrigerant high
pressure cut off switch which will stop the compressor if the condensing pressure becomes too high
due restricted condenser air flow or some other cause.
Restricted air flow due to neglecting a dirty filter will cause unit to repeatedly turn off and then turn
back on after it cools off. An operation in this safety cycling mode will eventually damage the equipment and
void the warranty.
Refer to Field Serviceable Parts section in this manual for details on parts that can be changed to help
increase the uninterruptable life of the Air Conditioner.
Air Filter Service
Remove the air conditioner filter and wash if washable or replace if not washable. Dry thoroughly
before replacing. DELTA-T Air Filter Treatment Spray in aerosol cans or spray bottle is recommended
to enhance air filter efficiency. Replacement filters are readily available from ISC Customer Service.
DO NOT operate the air conditioner without the air filter. Such operation will allow the condenser coil
to become dirty and loose efficiency, causing overheating and diminished cooling capacity. Dirty
condensing coils must be back-flush cleaned using proper commercial coil cleaning compounds and
thorough back-flush rinsing. Refer to directions on the cleaning compounds selected. Acid wash is not
recommended as it reduces the life of the coil.
Note: Do not use solvents to clean the programmable thermostat. Wipe with mild soap and water.
Condenser and Evaporator Fans
DELTA-T air conditioners use high efficiency, long life, sealed ball bearing fans engineered for
optimum performance that require no maintenance. Keep fan blades clean for optimal performance.
Fans are removable and attached by plug in connections.
Compressor
ISC uses hermetically factory sealed compressors that are quiet, low vibration and are maintenance
free. Thermal overload devices are installed to protect the compressor from damage due to overheat
and short cycle faults. If the compressor thermal overload fails, it is recommended to return the unit to
ISC customer service for proper replacement. Note that the rotary compressor runs with compressed
refrigerant gas on the outer case and therefore is hot to the touch.
Loss of Refrigerant
DELTA-T air conditioners are meticulously leak and run tested after assembly. If a leak in the system
should develop due to shipping damage or mechanical vibration, the leak must be detected, repaired
and the refrigerant charge restored to the system by a qualified refrigeration professional.
4421 Tradition Trail ● Plano, Texas 75093 ● 972 -964-2700 ● 800-836-7472
URL: www.iscenclosurecooling.com ● Email: iscinfo@iscsales.com
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Field Serviceable Parts
ISC carefully designs and selects components with the maximum life expectancy. Due to OEM
manufacturing tolerances, poor unit maintenance or extreme operating conditions, components may
fail before their maximum life expectancy. The table below lists parts that are serviceable in the field by
an Air Conditioner Technician.
Part Description
ISC Part #
Low Pressure Switch
52110-1
52112-1
52111-1
52111-2
38151-1
Condenser Fan Cut-In Pressure Switch
38006-1
Temperature Probe
Condenser Fan Relay
52126-1
55761-1 for 120VAC
55762-1 for 230VAC
Thermal Expansion Value TXV
32025-1
Compressor
31500-1 for 120VAC
31506-1 for 230VAC
Digital Controller
Gasket Installation Kit
Evaporator Fan
Condenser Fan
Filter Media
for
for
for
for
120VAC
230VAC
120VAC w/ both Dry C and Heater
230VAC w/ both Dry C and Heater
71300-N115
41004-1-1 for 120VAC
41004-2-1 for 230VAC
NE010: 41005-1-1 for 120VAC, 41005-2-1 for 230VAC
NE015: 41025-1-1 for 120VAC, 41025-2-1 for 230VAC
44008-1 (Available in packs of 12: Part # 44200)
Safety Information
Unit is carefully designed to restrict access to movable parts to minimize any potential injury. This Air
Conditioner has been tested by UL to meet the safety requirements of the UL484 specification. When
working with the DELTA-T Air Conditioner always makes sure shroud is installed. Verify proper
voltage is applied to unit as specified in the UL label of the Air Conditioner. In the event of a field
service repair, power down unit using the power on/off switch and disconnect power from unit. It is
always recommended to use a licensed Air Conditioner Technician for internal diagnostics and repairs
issues.
Contact ISC technical support for further details on opening the unit and troubleshooting tips.
4421 Tradition Trail ● Plano, Texas 75093 ● 972 -964-2700 ● 800-836-7472
URL: www.iscenclosurecooling.com ● Email: iscinfo@iscsales.com
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Troubleshooting Guide
The following guide provides a flow chart to identify a problem, determine the root cause and identify
the action needed to correct an issue.
Unit Will Not Run
Is Unit
Connected?
Verify Power On/Off
Switch is on position
YES
NO
OFF
Please Connect
Power Cord
Toggle Switch
then Retry
Verify input power
meets voltage
requirements as
shown in the UL label
ON
YES
If problem is still present contact
technical support
Unit Overheats /
Insufficient Cooling
NO
Is Filter
Clean?
YES
Are Condenser &
Evaporator Fans ON?
YES
Is Condenser
Coil dirty?
NO
NO
YES
Clean / Replace
Filter
Check for Faulty
Fan & replace
Clean Coil
Is Evaporator Coil
Frozen / Iced?
NO
Contact Qualified Refrigeration Service
Technician to check Refrigerant Pressure. Unit
may have a refrigeration leak. If problem is not
resolved contact technical support.
YES
Potential Bad
Evaporator Fan,
check for faulty
fan.
4421 Tradition Trail ● Plano, Texas 75093 ● 972 -964-2700 ● 800-836-7472
URL: www.iscenclosurecooling.com ● Email: iscinfo@iscsales.com
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NO
Unit Not Cooling
Is Compressor
On?
YES
Is evaporator
Fan on?
Measure Temperature at Evaporator
& Verify Heat Load Requirements. Is
unit capacity adequate for internal
head load? Possible low refrigerant.
YES
NO
NO
Check for faulty
3
evaporator fan
Check
Setpoint. Is
Setpoint
below
ambient?
YES
Is snowflake
LED lit on
controller?
YES
Is there voltage to
compressor? Use
3
meter
NO
NO
NO
Check for error code
Set Setpoint between
70 to 95 deg F
CA,LA,HA,LA2,HA2,
P1, or P2
NO
YES
Check contactor
circuit. Does it have
3
power?
NO
YES
Contact Customer
Support
Refer to Alarm Signals
in Digital Temperature
Controller
Programming Section
YES
Is compressor
thermal overload
open? Use ohm
3
meter.
YES
NO
YES
Verify contact coil is
being activated. Check
3
connectivity , if issue
persists component
replacement may be
needed.
Contact
Customer
Support
Replace Thermal
Overload.
Contact Customer
Support
*3 Note: Refer to Electrical Schematics for further diagnostics.
4421 Tradition Trail ● Plano, Texas 75093 ● 972 -964-2700 ● 800-836-7472
URL: www.iscenclosurecooling.com ● Email: iscinfo@iscsales.com
SP-ENG-210-100-09 Rev 1.6
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Single or
Multiple
Codes?
Flashing Error
Codes
P1 / P2
combination
flashing?
2+
Potential bad
connection. Check
green connector
behind controller.
YES
NO
1
CA
Refer to Alarm Signals
in Digital Temperature
Controller
Programming Section
Check Low Pressure
Switch Connections
and Verify Pressure
switch is closed. Use
3
meter.
YES
NO
P1 or
P2
YES
Check probe
connections, potential
faulty probe.
NO
LA, LA2, HA,
HA2
YES
Refer to Alarm Signals
in Digital Temperature
Controller
Programming Section
*3 Note: Refer to Electrical Schematics for further diagnostics.
Fuse / Circuit
Protection
Nuisance Trip
Is fuse opening as
soon as unit turns
on?
YES
Check incoming power
supply and connections
for potential short circuit
NO
YES
Check electrical specification.
Verify proper recommended fuse
has been selected.
Does fuse open
when compressor
starts?
NO
Check compressor, if excess heat present compressor may
be faulty. Contact Technical Support.
4421 Tradition Trail ● Plano, Texas 75093 ● 972 -964-2700 ● 800-836-7472
URL: www.iscenclosurecooling.com ● Email: iscinfo@iscsales.com
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Water overflow /
excessive
Check drain, is it
plugged?
NO
Is Air Conditioner sealed
against enclosure
properly, tightly sealed
and door closed?
NO
Ensure air tight
seal between air
conditioner and
enclosure. Make
sure door is
closed.
YES
YES
Clean condensate pan and
drain; add 1 tbsp bleach to
upper pan monthly to kill
mold
Contact Customer Service
Physical Dimensions
120 / 230 VAC Models
4421 Tradition Trail ● Plano, Texas 75093 ● 972 -964-2700 ● 800-836-7472
URL: www.iscenclosurecooling.com ● Email: iscinfo@iscsales.com
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THIS PAGE IS INTENTIONALLY LEFT BLANK
4421 Tradition Trail ● Plano, Texas 75093 ● 972 -964-2700 ● 800-836-7472
URL: www.iscenclosurecooling.com ● Email: iscinfo@iscsales.com
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Electrical Schematics
System Schematic
Digital Controller Schematic
Note: Schematics applies to all voltages; optional accessories wiring not provided in this document. If you
require electrical schematic with options contact our technical support and provide your model number.
4421 Tradition Trail ● Plano, Texas 75093 ● 972 -964-2700 ● 800-836-7472
URL: www.iscenclosurecooling.com ● Email: iscinfo@iscsales.com
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Warranty Information
ISC products are warranted to be free of defects in workmanship, materials and components. The
warranty period applies from date of shipment for one year.
The above warranty applies when the equipment is operated under the following conditions:

Ambient temperature not in excess of performance rating in norm al atmosphere or as stated on
product nameplate

Voltage variation no greater than ± 10% from nameplate rating

Frequency variation no greater than ± 3Hz from nameplate rating

Maximum cooling load no higher than air conditioner nameplate rating

Waiting five minutes before restarting air conditioner after intentional or accidental shutoff

Compliance to all other installation, maintenance and oper ating instructions, as supplied
ISC cannot assume responsibility for misapplication of its products or the erroneous selection of an
inappropriate product by a non-authorized ISC representative. Our applications engineers will gladly
assist in the selection of the proper product provided all required details of the application are furnished.
ISC assumes no liability beyond the repair or replacement of its own product. This Warranty does not
cover:

Labor or reimbursement of labor for evaluation, removal, installation, repair, or cost of any
warranted part, except at the ISC factory in Dallas, Texas

Use of equipment for other than its designed purpose or operating conditions

Operation in harsh, oily, corrosive or other abnormal environmental conditions, without the proper
filtration, sealing, protective coatings and/or weather protection

Damage to hermetic system resulting from continuous operation with dirty or clogged air filters or
improper or negligent maintenance

Use of refrigerant other than designated

Customer modification or abuse

Shipping damage or other accident

Repair or service by unauthorized personnel.
Cracked or broken hermetic tubing or brazed joints caused by shipping damage or mishandling are not
covered under the Warranty. Claims for shipping damage are the responsibility of the Consignee. Timely
claims must be filed with the freight carrier.
The purchaser assumes the responsibility of grounding the unit and installing it in accordance with local
electrical and safety codes, as well as the 2008 National Electric Code (NEC) and OSHA.
THIS WARRANTY CONSTITUTES THE ENTIRE WARRANTY WITH RESPECT TO THE PRODUCT AND
IS IN LIEU OF ALL OTHERS, EXPRESSED OR IMPLIED, INCLUDING ANY WARRANTY OF
MERCHANTABILITY AND WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE AND IN NO
EVENT IS ISC RESPONSIBLE FOR ANY CONSEQUENTIAL DAMAGES OF ANY NATURE
WHATSOEVER.
4421 Tradition Trail ● Plano, Texas 75093 ● 972 -964-2700 ● 800-836-7472
URL: www.iscenclosurecooling.com ● Email: iscinfo@iscsales.com
SP-ENG-210-100-09 Rev 1.6
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Return Material Authorization (RMA) Procedure
All returns require a Return Material Authorization (RMA) number for warranty or non-warranty repair, rotation
of stock, damage or any other reason.
IMPORTANT
Returns without an RMA number will be refused and returned. Improper packaging may void
warranty. Air Conditioners shipped laying down will void the warranty. Collect shipments will be
refused.
Please be ready to provide:

Purchase Order Number & Date

Product Description & Reason for Request

Model Number & Serial Number

Customer name and contact info (email, phone number and address)

Shipping method
Pack unit in a suitable packing for shipment, preferably the original packaging if available.

If suitable packing is not available, arrange for packaging to be shipped to you.

Air Conditioners must be returned in an upright position properly secured to a pallet.

Tip unit to empty water from the evaporator and boil off pans.

Clearly mark the RMA number on the box.

Customer will pay all freight charges.
Out of Warranty Repair
If your ISC air conditioner is out of warranty and requires repair, simply call ISC Customer Service at (800)836-7472 for an RMA number. Customer Service will help you determine what repairs or parts are needed
and, if possible, an estimate of the cost.
After the unit is received and diagnosed, you will receive a ship estimate on the work and parts needed. The
repairs and test process may uncover other issues for which you will be informed and given quotes for the
work needed.
4421 Tradition Trail ● Plano, Texas 75093 ● 972 -964-2700 ● 800-836-7472
URL: www.iscenclosurecooling.com ● Email: iscinfo@iscsales.com
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