Stulz CeilAiR Series Instruction manual

(Mar, 2012)
CeilAiR OHS Series Installation, Operation & Maintenance Manual
A
ir Technology Systems, Inc.

(Mar, 2012)
CeilAiR OHS Series Installation, Operation & Maintenance Manual
A
ir Technology Systems, Inc.
MODEL NOMENCLATURE
OHS-040-G-FC
OHS = Overhead System
Nominal Capacity in 1,000’s of BTU/Hr
AWS = Alternate Water Source
FC = Free Cooling
LP = Low Profile Configuration
SF = Same-Face Air Pattern
SP = Special Configuration
AHU = Air Handling Unit
AR = Air-Cooled Remote (Split)
AS = Air-Cooled Self-Contained
C = Chilled Water System
CAA = Indoor Centrifugal Condenser
D( ) = Dual (Two) Circuit System
G = Glycol-Cooled
H( ) = Horizontal Discharge (“H-Series”)
RCU-I = Indoor Centrifugal Remote
Condensing Unit
W = Water Cooled

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1.0 Introduction ............................................1-1
1.1 General.....................................................1-1
1.2 Product Description..................................1-1
1.3 Controls....................................................1-2
1.4 Product Warranty .....................................1-3
1.5 Safety .......................................................1-4
1.5.1 General.....................................................1-4
1.5.2 Safety Summary.......................................1-4
1.6. General Design ........................................1-6
2.0 Installation ..............................................2-1
2.1 Receiving the Equipment. ........................2-1
2.2 Site Preparation........................................2-1
2.3 Rigging .....................................................2-1
2.4 Mounting...................................................2-2
2.4.1 Indoor Equipment.....................................2-2
2.4.2 Outdoor Equipment ..................................2-2
2.4.3 Controls....................................................2-2
2.4.4 Optional Equipment..................................2-3
2.4.4.1 Transformer..............................................2-3
2.4.4.2 Condensate Pump (Field Inst.).................2-4
2.4.4.3 Non-fused Service Switch ........................2-4
2.4.5 Remote Sensors.......................................2-4
2.4.5.1 Remote Temperature Sensor ...................2-4
2.4.5.2 Remote Temperature/Humidity Sensor ....2-4
2.4.5.3 Remote Water Detector............................2-4
2.4.5.4 Cable Type Water Detector ......................2-4
2.5 Air Distribution Connection.......................2-5
2.5.1 Spot Cooler ..............................................2-5
2.5.2 Ducted Systems .......................................2-6
2.6 Piping Connections ..................................2-6
2.6.1 Refrigerant................................................2-6
2.6.2 Chilled Water and Water/Glycol ...............2-8
2.6.3 Condensate Drain Line.............................2-9
2.6.4 Humidifier (Optional) ................................2-9
2.7 Utility Connections..................................2-10
2.7.1 Main Power ............................................2-10
2.7.2 Controls..................................................2-12
2.7.3 Optional Equipment................................2-15
2.7.3.1 Condensate Pump..................................2-15
2.7.3.2 Remote Temperature Sensor .................2-15
TABLE OF CONTENTS
2.7.3.3 Remote Water Detector..........................2-15
2.7.4 Air-Cooled Split Systems........................2-16
2.7.4.1 Remote Condenser ................................2-16
2.7.4.2 Remote Condensing Unit .......................2-16
2.7.5 Glycol Systems.......................................2-16
2.7.6 Remote Shut Down ................................2-19
2.8 System Charging Procedures ................2-19
2.8.1 R22 Refrigerant Charging Procedures...2-19
2.8.2 R407C Refrigerant Charging Procedures.... 2-20
2.9 System Settings & Adjustments .............2-19
2.9.1 Low/High Limit Switch ...........................2-21
2.9.2 Head Pressure Controls- Air Cooled
Systems..................................................2-22
2.9.3 Head Pressure Controls- Water/Glycol .........
Cooled Systems .....................................2-23
2.9.4 Humidifier Adjustment ............................2-23
2.9.5 Belt Drive Blower....................................2-24
2.9.6 Thermal Expansion Valve.......................2-24
2.9.7 Hot Gas Reheat......................................2-24
2.9.8 Hot Gas Bypass .....................................2-24
2.10 Refrigerant Pressure Characteristics .....2-26
3.0 Start-Up / Commissioning .....................3-1
3.1 Operation..................................................3-1
3.2 Step by Step Start-Up Instructions...........3-1
3.3 Thermostat Programming.........................3-2
3.3.1 A-Tech-1.1................................................3-2
3.3.2 A-Tech-1.2................................................3-5
3.3.3 Advanced E² Controller ...........................3-7
4.0 Maintenance............................................4-1
4.1 Periodic General Maintenance.................4-1
4.1.1 Precision A/C Unit ....................................4-1
4.1.2 Condensing Unit.......................................4-2
4.2 Troubleshooting........................................4-2
4.3 Field Service.............................................4-6
4.3.1 Refrigerant Piping.....................................4-6
4.3.2 Leak Detection .........................................4-6
4.3.3 Leak Repair..............................................4-6
4.3.4 General Common Repairs/Component
Replacement ............................................4-6
4.3.4.1 Compressor Failure..................................4-6
i

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List of Figures
Figure 1 Typical Installation.................................2-2
Figure 2 Spot Cooler Grille..................................2-5
Figure 3 Ducted System Typical Air Patterns ......2-6
Figure 4 Condensate Pump ................................2-9
Figure 5 Sample Nameplate .............................2-10
Figure 6 Transformer Schematic....................... 2-11
Figure 7 A-Tech-1.1 Control Wiring ...................2-13
Figure 8 A-Tech-1.2 Control Wiring ...................2-15
TABLE OF CONTENTS (Continued)
ii
4.3.4.2 Standard Cleanout Procedure..................4-7
4.3.4.3 Burn-Out/Acidic Cleanup Procedure ........4-7
4.3.4.4 Humidifier Cylinder Replacement.............4-7
4.3.4.5 Filter Replacement ...................................4-8
5.0 Product Support.....................................5-1
5.1 Technical Support.....................................5-1
5.2 Obtaining Warranty Parts .........................5-1
5.3 Obtaining Spare/Replacement Parts........5-1 Glycol Systems ...................................2-18
Figure 13 Belt Drive Blower ................................2-24
Figure 14 A-Tech-1.1 Control Panel......................3-2
Figure 15 A-Tech-1.2 Control Panel......................3-5
Appendix A – Forms
Checklist for Completed Installation ........................ A-1
Periodic General Maintenance Checks
and Service Checklist.............................................. A-2
Appendix B – Glossary
Definition of Terms and Acronyms ........................... B-1
List of Figures (Cont.)
Figure 9 Interconnecting Field Wiring Remote
Condenser ..........................................2-17
Figure 10 Interconnecting Field Wiring Remote
Condensing Unit (A-Tech-1.1/1.2) ......2-17
Figure 11 Interconnecting Field Wiring Remote
Condensing Unit (A-Tech-20)..............2-17
Figure 12 Interconnecting Field Wiring
Notice
This document contains information protected by copyright. All rights are reserved. The owner of the equipment
for which this manual is written may photocopy the contents of this manual for internal use only. No part of this
document may be photocopied, reproduced, or translated into another language for use by anyone other than the
owner of the equipment for which this manual is written without the prior written consent of Stulz Air Technology
Systems, Inc. (SATS).
This document contains confidential and proprietary information of Stulz Air Technology Systems, Inc. Distributing
or photocopying this document for external distribution is in direct violation of U.S. copyright laws and is strictly
prohibited without the express written consent of SATS.
Unpublished — rights reserved under the copyright laws of the United States and of other countries.
Other brands and tradenames are trademarks of their respective owners.
Copyright 2007 by Stulz Air Technology Systems, Inc.
Printed in the United States of America.
All rights reserved.
Stulz Air Technology Systems, Inc.
1572 Tilco Drive
Frederick, MD 21704
USA

(Mar, 2012)
CeilAiR OHS Series Installation, Operation & Maintenance Manual
A
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1.0 Introduction
1.1 General
Thank you for your selection of the CeilAiR® ceiling-
mounted air conditioning system made by Stulz Air
Technology Systems, Inc.
CeilAiR overhead air conditioning systems (OHS) are
designed and constructed using the finest available
materials/components, state-of-the-art technology
and quality craftsmanship to provide years of trouble-
free service. Due to technological advancement, all
components are subject to change without notice.
All CeilAiR OHS systems and CyberAiR® centrifugal
condensers are designed to be installed indoors,
unless otherwise noted on the equipment. Propeller-
type condensers, condensing units, drycoolers and
pump packages are designed for outdoor use.
1.2 Product Description
CeilAiR OHS systems are designed to be the most
versatile and flexible ceiling-mounted air condition-
ing systems in the industry. The unit is available in
air-cooled, water-cooled, glycol-cooled and chilled-
water configurations. The cooling capacity in BTU/Hr
will depend on the unit size, which can range from 1
to 10 tons, and can be either a single stage or dual
stage unit.
The functional modes of operation, in addition to
cooling, are heating, humidification, dehumidification
and filtration, which provides complete environmental
control of a conditioned space. The cabinet
configuration is available in a 2’ x 4’ frame for units
ranging from 12,000 to 40,000 BTU/Hr (spot cooler
or ducted) or a larger frame for units ranging from
48,000 to 120,000 BTU/Hr (ducted only). For ducted
units, there are three basic configurations of airflow
patterns: 90º/Right Angle, Straight-Thru and In/
Out Same-Face (reference Figure 3). Refer to the
installation drawing provided with your unit for the
type of cabinet configuration and for the layout
dimensions.
1.3 Controls
SATS offers a wide variety of control options for
CeilAir OHS series A/C systems. The controllers are
typically remotely mounted to a wall or control panel.
Your unit may be furnished with a Digital Thermostat
offered for basic control of Ceilair OHS systems. The
A-Tech 1.1 is utilized for single stage units and the A-
Tech 1.2 is utilized for dual stage units (see Section
3.3.2).
The advanced E² microprocessor controller is now
available for Ceilair OHS systems which provides
enhanced features for more comprehensive control
of the unit. These features include: full alarm system;
input/output monitoring status; full integrated control
of heating, cooling, humidification, and dehumidifica-
tion; multi-unit control and remote communication
with building management systems.
1-1
If your unit is equipped with an E² controller, an operating manual is provided under separate cover. Refer to
that manual for detailed instructions on operating the system controller.
A-Tech- 1.2A-Tech-1.1
Digital Thermostats Advanced E² Microprocessor
Controller
E² Controller Display

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STULZ AIR TECHNOLOGY SYSTEMS, INC.
12 MONTH PRECISION A/C LIMITED WARRANTY /
24 MONTHS PRECISION A/C UPGRADED LIMITED WARRANTY
The 12 month Precision A/C Limited Warranty applies when the Product Support Network
Factory Start-Up is not purchased at the time of order entry.
The 24 Month Precision A/C Upgraded Limited Warranty applies only if Factory Start-Up was
purchased at the time of Order Entry and Start-Up has been validated by Product Support.
The 12 Month Precision A/C Limited Warranty provided by Stulz Air Technology Systems, Inc. (SATS) warrants
your purchase to be free from defects in material and workmanship. SATS’ obligation under this warranty is to
repair or replace, at its option, any part or parts which are determined by SATS to be defective for a period of 12
months from the date of shipment when an accurately completed Factory Start-Up Form has been submitted to
SATS, within 180 days from shipment. Parts repaired or replaced under this warranty are shipped FOB Factory,
and warranted for the balance of the original warranty period or for 90 days from the date of installation, whichever
is greater. If the Factory Start-Up form is not returned to SATS within 180 days from the date of equipment
shipment, the equipment warranty will be terminated on the 181st day from shipment. This limited warranty does
not include labor, freon, or any other expense required to replace the defective component and bring the unit back
to a working status.
The 24 Month Precision A/C, Upgraded Limited, Warranty provided by Stulz Air Technology Systems, Inc. (SATS)
warrants your purchase to be free from defects in material and workmanship for 24 months. SATS obligation under
this warranty is to repair or replace, at its option, any part or parts which are determined by SATS to be defective
for a period of 24 months from the date of start-up. Parts repaired or replaced under this warranty are shipped
FOB factory ground, and warranted for the balance of the original warranty period or for 90 days from the date of
installation, whichever is greater. If the factory is not allowed to start the equipment within 180 days from the date
of shipment, the warranty will commence on the 181st day from equipment shipment. This limited warranty does
not include labor, freon, or any other expense required to replace the defective component and bring the unit back
to a working status.
Stulz Air Technology System’s warranty does not cover failures caused by improper installation, abuse, misuse,
alteration, misapplication, improper or lack of maintenance, negligence, accident, normal deterioration (including
wear and tear), or the use of improper parts or improper repair.
Purchaser’s remedies are limited to replacement or repair of non-conforming materials in accordance with the
written warranty. This warranty does not include costs for transportation, travel expenses, costs for removal or
reinstallation of equipment or labor for repairs or replacements made in the field.
If any sample was shown to the buyer, such sample was merely to illustrate the general type and quality of the
product, and not to represent that the equipment would necessarily conform to the sample.
This is the only warranty given by the seller, and such warranty is only given to buyer for commercial or industrial
purposes. The warranty is not enforceable until the invoice(s) is paid in full.
THIS FOREGOING SHALL CONSTITUTE SATS’ ENTIRE LIABILITY AND YOUR EXCLUSIVE
REMEDY. IN NO EVENT SHALL SATS BE LIABLE FOR ANY DEFECT, INDIRECT, SPECIAL,
INCIDENTAL, CONSEQUENTIAL, OR EXEMPLARY DAMAGES, INCLUDING LOST PROFITS (EVEN
IF ADVISED OF THE POSSIBILITY THEREOF) ARISING IN ANY WAY OUT OF THE INSTALLATION,
USE OR MAINTENANCE OF THE EQUIPMENT. THIS WARRANTY IS IN LIEU OF ALL OTHER
WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE.
This warranty supersedes all other previously printed warranties dated prior to this document.
WARF-1001 Rev. B; 9/20/10




1.4 Product Warranty

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

 
STULZ AIR TECHNOLOGY SYSTEMS, INC.
OPTIONAL 60 MONTH COMPRESSOR LIMITED WARRANTY
This warranty applies only when the Product Support Network Factory Start-Up is purchased at
the time of order entry.
SATS#:
Unit Serial #:
Unit Model #:
Warranty Start Date:
Warranty End Date:
Compressor 1 Serial #:
Compressor 2 Serial #:
Stulz Air Technology Systems, Inc. (SATS) warrants your purchase to be free from defects in material and
workmanship for 60 months (original standard 24 months and purchased additional 36 months). SATS’ obligation
under this warranty is to repair or replace, at its option, free of charge to the customer, any part or parts which are
determined by SATS to be defective for a period of 60 months from the date of start-up. Start-up must be completed
within the first 180 days from shipment. The 60 month warranty only covers original compressor(s) that were installed
by SATS or a original equipment supplier contracted by SATS to manufacture equipment solely for SATS.
Compressors replaced under this warranty are shipped FOB factory ground, and warranted for the balance of
the original warranty period or for 90 days from the date of installation, whichever is greater. If the factory is not
allowed to start up the equipment within 180 days from the date of shipment, the warranty will commence on the
181st day from equipment shipment
Stulz Air Technology System’s warranty does not cover failures caused by improper installation, abuse, misuse,
alteration, misapplication, improper or lack of maintenance, negligence, accident, normal deterioration (including
wear and tear), or the use of improper parts or improper repair. Purchaser’s remedies are limited to replacement
or repair of non-conforming materials in accordance with the written warranty. This warranty does not include cost
for torch charges, reclaim charges, Freon, transportation, travel expenses, costs for removal or reinstallation of
equipment or labor for repairs or replacements made in the field.
If any sample was shown to the buyer, such sample was merely to illustrate the general type and quality of the
product, and not to represent that the equipment would necessarily conform to the sample.
This is the only warranty given by the seller, and such warranty is only given to buyers for commercial or industrial
purposes. The warranty is not enforceable until the invoice(s) is paid in full.
THIS FOREGOING SHALL CONSTITUTE SATS’ ENTIRE LIABILITY AND YOUR EXCLUSIVE
REMEDY. IN NO EVENT SHALL SATS BE LIABLE FOR ANY DEFECT, INDIRECT, SPECIAL,
INCIDENTAL, CONSEQUENTIAL, OR EXEMPLARY DAMAGES, INCLUDING LOST PROFITS (EVEN
IF ADVISED OF THE POSSIBILITY THEREOF) ARISING IN ANY WAY OUT OF THE INSTALLATION,
USE OR MAINTENANCE OF THE EQUIPMENT. THIS WARRANTY IS IN LIEU OF ALL OTHER
WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE.
This warranty supersedes all other previously printed warranties dated prior to this document.
WARF-1003 Rev. A; 8/30/10
SATS offers a two year standard limited warranty as stated on the previous page. Additionally an extended war-
ranty may be purchased on the unit’s compressor. The compressor warranty as stated below will be sent with
your unit if the option is purchased and should be retained for future reference. You may consult the factory to
verify if the extended compressor warranty was purchased for your system.

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1.5 Safety
1.5.1 General
Stulz Air Technology Systems, Inc. uses notes along
with caution and warning symbols throughout this
manual to draw your attention to important opera-
tional and safety information.
A bold text NOTE marks a short message in the infor-
mation to alert you to an important detail.
A bold text CAUTION safety alert appears with infor-
mation that is important for protecting your equipment
and performance. Be especially careful to read and
follow all cautions that apply to your application.
A bold text WARNING safety alert appears with infor-
mation that is important for protecting you from harm
and the equipment from damage. Pay very close at-
tention to all warnings that apply to your application.
A safety alert symbol precedes a general
WARNING or CAUTION safety statement.
A safety alert symbol precedes an electri-
cal shock hazard WARNING or CAUTION safety
statement.
1.5.2 Safety Summary
The following statements are general guidelines fol-
lowed by warnings and cautions applicable through-
out the manual.
Prior to performing any installation, operation,
maintenance or troubleshooting procedure read and
understand all instructions, recommendations and
guidelines contained within this manual.
WARNING
This equipment should be serviced and re-
paired by a journeyman, refrigeration mechanic
or an air conditioning technician.
WARNING
Hazardous voltage will still be present inside
the electric box, even with the unit turned off
at the system controller. To isolate the unit for
maintenance, turn off power at the main power
disconnect switch. Always disconnect main
power prior to performing any service or repairs.
WARNING
To prevent personal injury, stay clear of rotating
components as automatic controls may start
them unexpectedly. Turn off power to the unit
unless you are performing tests that require
power. With power and controls energized, the
unit could begin operating at any time.
WARNING
Never operate the unit with any cover, guard,
screen panel, etc. removed unless the instruc-
tions specifically state otherwise, then do so
with extreme caution to avoid personal injury.
CAUTION
Never lift any component in excess of 35
pounds without help. If a lifting device is used
to move a unit ensure it is capable of support-
ing the unit.
CAUTION
Do not allow the unit to swing while suspended
from a lifting device. Failure to observe this
warning may result in injury to personnel and
damage to the equipment.
CAUTION
When transporting and installing the A/C unit, it
must be kept in its normal, horizontally installed
position. If the unit is not kept level and hori-
zontal, damage to the compressor(s) will result.
WARNING
Always disconnect the main power supply
before beginning work on the equipment. A
lock-out tag-out procedure should be followed
to ensure that power is not inadvertently recon-
nected.
Never work on electrical equipment unless an-
other person who is familiar with the operation
and hazards of the equipment and competent
in administering first aid is nearby.
All personnel working on or near equipment
should be familiar with hazards associated with
electrical maintenance. Safety placards/stickers
have been placed on the unit to call attention to all
personal and equipment damage hazard areas.
1-4

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WARNING
This unit employs high voltage equipment with
rotating components. Exercise extreme care to
avoid accidents and ensure proper operation.
WARNING
When working on electrical equipment, remove
all jewelry, watches, rings, etc.
WARNING
Refrigerant (R407C or R410A) is used with this
equipment. Death or serious injury may result if
personnel fail to observe proper safety precau-
tions. Great care must be exercised to prevent
contact of liquid refrigerant or refrigerant gas,
discharged under pressure, with any part of the
body. The extremely low temperature resulting
from the rapid expansion of liquid refrigerant
or pressurized gas can cause sudden and ir-
reversible tissue damage.
As a minimum, all personnel should wear ther-
mal protective gloves and face-shield/goggles
when working with refrigerant. Application of
excessive heat to any component will cause
extreme pressure and may result in a rupture.
Exposure of refrigerant to an open flame or a
very hot surface will cause a chemical reaction
that will form carbonyl chloride (hydrochloric/hy-
drofluoric acid); a highly poisonous and corro-
sive gas commonly referred to as PHOSGENE.
In its natural state, refrigerant is a colorless,
odorless vapor with no toxic characteristics. It
is heavier than air and will disperse rapidly in
a well-ventilated area. In an unventilated area,
it presents a danger as a suffocant.
Always refer to the manufacturer’s MSDS pro-
vided with the unit.
WARNING
When performing soldering or desoldering op-
erations, make certain the refrigeration system
is fully recovered and purged and dry nitrogen
is flowing through the system at the rate of not
less than 1-2 CFM (0.028-0.57 M ³/minute).
1-5
CAUTION
Certain maintenance or cleaning procedures
may call for the use and handling of chemi-
cals, solvents, or cleansers. Always refer to
the manufacturer’s Material Safety Data Sheet
(MSDS) prior to using these materials. Clean
parts in a well-ventilated area. Avoid inhalation
of solvent fumes and prolonged exposure of
skin to cleaning solvents. Wash exposed skin
thoroughly after contact with solvents.
CAUTION
Do not use cleaning solvents near open flame
or excessive heat. Wear eye protection when
blowing solvent from parts. The pressure-wash
should not exceed 30 psig. Solvent solutions
should be disposed of in accordance with local
and state regulatory statutes.
CAUTION
When the air conditioner is in the cooling mode,
the return air-intake and discharge (supply)
must be free of obstructions. Ensure panels
are secure and latched into position.
CAUTION
DX and chilled water cooling coils (and associ-
ated piping circuits) are pressurized and sealed
when they leave the factory. Before installing
the interconnecting piping, observe appropriate
safety precautions and release the pressure via
an available stem valve or schrader valve prior
to uncapping the pipes.
CAUTION
When installing and filling the water/glycol loop,
all air must be bled from the piping system and
the piping system must be cleaned prior to add-
ing the solution. Failure to do so will result in
equipment problems.
WARNING
Do not use chloride based water conditioning
additives in the condensate drain pans. This will
cause corrosion to occur on the coil fins.

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1.6 General Design
The CeilAiR unit is housed in an aluminum frame type cabinet and is rated for indoor use. Access panels are lo-
cated on the front and rear of the cabinet for easy access to all components. Additional access may be obtained
to some components through the bottom of the unit on spot cooler configurations. The unit has an electrical box
inside the cabinet with a removable panel for accessing the electrical components. Operator controls may be
conveniently located on a wall within the space to be conditioned.
NOTE
Customer specified non standard features or design variations may not be described in this manual. Refer
to the installation and electrical drawings supplied with your unit for details on additional feature(s). In some
cases, an addendum to this manual may also be included to further describe the feature(s).
1-6
1.6.1 Electric Box Access
The electrical components are protected in an enclo-
sure located in the cabinet behind an access panel.
Before opening the access panel, turn off power
at the main power service disconnect switch. This
removes power from the system controller and shuts
the unit off.
1.6.2 Coil(s)
The cooling and optional hot water reheating coils
are aluminum finned/copper tube construction. The
coils are leak tested and cleaned before installation
by the factory.
1.6.3 Blower
The unit is equipped with a centrifugal blower with
forward curved blades. The blower is contained in
a double-width, double-inlet housing. The blower is
dynamically and statically balanced to minimize vi-
bration. The blower motor is ODP industrial duty and
utilizes permanently lubricated ball bearings.
Smaller CeilAiR units (models OHS-012/040) use
direct drive blowers (except “H”-series models config-
ured for horizontal discharge).
Larger units (models OHS-048/120) and horizontal
discharge units (models OHS-012/040-H), use a
belt driven blower. The belt driven blower motor is
mounted on an adjustable base for belt tensioning
and is furnished with an adjustable pitch sheave to
adjust blower speed (see Figure 13).
1.6.3.1 EC Blower
As an option, CeilAiR OHS units utilizing the E²
controller may be provided with high efficiency
Electronically Commutated (EC) blower(s). The EC
blowers are equipped with backwards curved impel-
lers designed for high aerodynamic efficiency, which
results in lower power consumption, lower noise
levels and longer operating life. EC blowers utilize
a brushless motor equipped with permanent mag-
nets and permanently lubricated ball bearing. The
fan speed is variable via a 0-10VDC signal from the
system controller..
1.6.4 Temperature Sensor
As a standard for systems utilizing a wall mounted
A-Tech 1.1 or A-Tech 1.2 thermostat, the temperature
sensor is built into the thermostat for room air con-
trol. The sensor monitors the room air conditions and
provides input signal(s) to the system controller. The
system controller manages the operation of the A/C
unit consistent with the set points entered.
As an option, the temperature sensor may be
shipped loose for field installation in the room to be
conditioned. Refer to the electrical drawing supplied
with your unit for details specific to your system.
Ceilair Model OHS-024-AHU
Shown for Reference
(Access Panels Removed)

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1.6.5 Optional Equipment
1.6.5.1 Humidistat/Dehumidistat
As an option for systems utilizing an A-Tech 1.1 or
A-Tech 1.2 thermostat, a room mounted humidistat
and/or dehumidistat may be shipped loose for field
installation. Each device has an adjustment dial
on the front where the operator selects the desired
setpoint.
If an optional humidifier is selected, the humidistat
is included to control it’s operation. The humidistat
controls the humidifier’s operation independent of the
control thermostat however, the blower must be on
for the humidifier to operate.
If the heat/reheat option is selected, a dehumidistat is
provided. If room humidity rises above setpoint when the
demand for cooling is satisfied, the dehumidistat signals
the compressor to turn on, removing humidity. At the
same time, the heater(s) are turned on to offset the cool-
ing effect thus maintaining the temperature of the space
to be conditioned. Refer to the electrical drawing supplied
with your unit for details specific to your system.
1.6.5.2 Temperature/Humidity Sensor
As a standard for systems utilizing the E² micro-
processor controller, a temperature/humidity (T/H)
sensor is typically factory mounted in the return air
stream for room air control. As an option, the T/H
sensor may be shipped loose for field installation.
Refer to the electrical drawing supplied with your unit
for details specific to your system.
1.6.5.3 Heaters
The precision A/C unit may incorporate heaters for
reheating the supply air as required to offset the
sensible cooling of the system during the dehumidifi-
cation cycle and, for the automatic heating mode. Ni-
chrome wire electric resistance heating elements are
factory installed in the supply air stream to heat the
supply air. The heating elements are protected with
line fuses, thermal fuse links and over-temperature
safety switches which automatically reset.
As an option, hot water reheat may be selected for
automatic sensible reheating during the dehumidifica-
tion cycle. A hot water heating coil is factory installed
in the supply air stream. A valve is provided to control
the flow of hot water through the coil to maintain the
correct reheat temperature.
Hot Gas Reheat may be selected (for CeilAiR units
with DX cooling only) for automatic sensible reheat-
1-7
ing during the dehumidification cycle. Hot compres-
sor discharge gas is diverted from the condenser to a
hot gas heating coil mounted in the supply air stream.
1.6.5.4 Humidifier
CeilAiR systems may utilize an optional electrode
steam humidifier. The humidifier is factory installed
inside the air conditioner and includes fill and drain
valves and associated piping. Operation of the
humidifier’s fill and drain cycles is based on water
conductivity and is maintained by the humidifier
controller. An operating manual for the humidifier is
provided under separate cover. Refer to that manual
for detailed information on operation of the humidifier.
1.6.5.5 Condensate Pump
An optional factory installed condensate pump may
be provided. The pump automatically eliminates
condensate and humidifier flush water (if applicable)
from the drain pan. Should an overflow occur, an
internal overflow safety switch is wired to the system
controller to signal the alarm condition and automati-
cally shut down the compressor and optional humidi-
fier until the condition is corrected. The blower(s) will
continue to operate.
1.6.5.6 Smoke Detector
Optionally mounted in the return air stream, a photo-
electric smoke detector is used to sense the pres-
ence of smoke and signal the controller when a
smoke alarm condition exists and shuts down the air
conditioner.
1.6.5.7 Firestat
Optionally mounted in the return air stream, a fire de-
tector senses high return air temperature and signals
the controller when a fire alarm condition exists and
shuts down the air conditioner.
1.6.5.8 Water Detector
As an option, SATS offers spot type or strip/cable
type water detectors. Upon sensing a water leak,
the water detector control circuit will signal the A/C
system controller of the alarm condition and shut
down the air conditioner if your unit is equipped
with an A-Tech 1.1 or A-Tech 1.2 thermostat. If your
unit is equipped with an E² controller, the default
program turns off cooling and humidification while
the blower(s) continue to operate. The unit will
automatically restart when the condition is corrected.

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2.0 Installation
2.1 Receiving the Equipment
Your CeilAiR OHS system has been tested
and inspected prior to shipment. To ensure that
your equipment has been received in excellent
condition, make a visual inspection of the equipment
immediately upon delivery. Carefully remove the
shipping container and all protective packaging.
Remove the access panels and thoroughly inspect
the unit interior for any signs of transit-incurred
damage. If there is shipping damage, it must be
noted on the freight carrier’s delivery forms BEFORE
signing for the equipment. Any freight claims MUST
be done through the freight carrier. SATS ships all
equipment FOB. SATS can assist in the claim filing
process with the freight carrier. Should any damage
be present, notify the SATS Product Support Group
prior to attempting any repairs. Refer to section five
of this manual for instructions.
A unit Data Package has been sent with your unit. It
contains this manual, system drawings, applicable
MSDS’s, other component manuals and any other
applicable instructions based on the configuration
and options of your unit. The data package has been
affixed to your unit in a clear plastic bag. These docu-
ments need to be kept with the unit for future service.
NOTE
Items that have been shipped loose such as
controllers, humidistats, vibration isolators,
buck/boost transformers, etc. are shipped
inside the air conditioner unless specified
otherwise by the customer. Grilles (if applicable)
are placed on top of the air conditioner inside
the unit’s carton. Remove and store these items
in a safe place unless you are using them im-
mediately.
2.2 Site Preparation
CeilAiR systems are designed with easy service
access in mind. Component access panels are
located on the front and rear sides of the equipment.
Additional access to some components may be
obtained through the bottom of the unit on spot
cooler configurations. These units can be fully
serviced in the ceiling plenum. In order to have full
service access, the air conditioner must be located
so that adequate space is provided in front of all
access panels.
NOTE
Working clearance requirements need to be
established prior to the mounting of the unit.
Refer to local and national electrical codes.
To minimize the effects of the environment
surrounding the conditioned space, certain steps
must be taken. This is especially true for critical/
precision room preparation (computer rooms/labs)
requiring close tolerance control of temperature
and humidity. The conditioned space should be well
insulated and include a vapor barrier. The installer
should ensure that the proper insulation rating is
used based on the design of the space, which was the
basis for the system selected. The following chart is a
recommended minimum R-value (thermal resistance) to
ensure optimum equipment operation.
The vapor barrier is the single most important
requirement for maintaining environmental control
in the conditioned space. The vapor barrier in
the ceiling and walls can be polyethylene film.
Concrete walls and floors should be painted with a
rubber or plastic-based paint. Doors and windows
should be properly sealed and a door sweep used
to minimize leakage. Outside or fresh air should
be kept to a minimum (as it adds to the cooling,
heating, dehumidification and humidifying loads),
while maintaining the requirement of the Indoor Air
Quality (IAQ) Standard. Lack of these steps can
cause erratic operation, unstable room control and
excessive maintenance costs.
2.3 Rigging
CeilAiR systems are designed to be kept in a
horizontal position. The unit is shipped on a skid to
facilitate moving prior to installation. A suitable lifting
device should be used to lift the unit from the bottom.
A weight table is provided for reference on the
installation drawing. The unit should always be stored
indoors in a dry location prior to installation.
STRUCTURE R-VALUE
Ceiling R-38
Wall R-21
Floor R-19
Door R-5
2-1

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CAUTION
When moving the unit, it must be kept level and in
the horizontal position to prevent damage.
2.4 Mounting
CeilAiR OHS systems are designed for ceiling
mounting in a suspended ceiling grid (spot cooler) or
above the suspended ceiling for ducted systems.
NOTE
Do not install the A/C system directly above
electronic equipment which may hinder
serviceability.
2.4.1 Indoor Equipment (See Figure 1)
CeilAiR OHS systems use a frame and panel
configuration for unit rigidity and full service
accessibility while the unit is mounted in place.
The units are lifted into place from underneath and
secured into place using all-thread rods passing
through rubber grommets or a 4” x 4” neoprene cork
pad in the mounting arms on the sides of the unit. All-
thread, nuts and washers (field supplied by others)
must be secured so they do not loosen.
Before mounting the unit, ensure the mounting struc-
ture is able to support the weight of the equipment.
Refer to the weight table provided on the installation
drawing. Locate the mounting bolt holes or match drill
through the support locations as needed and secure
the unit with suitable hardware for the application.
An auxiliary drain pan is recommended and can be
mounted directly under the cabinet (only on ducted
models).
2.4.2 Outdoor Equipment
Install remote condensers/condensing units in a se-
cure location where the unit cannot be tampered with
and the power service switch cannot be inadvertently
turned off. Locate the remote condenser/condens-
ing unit where the fan is not likely to draw dirt and
debris into the coil fins. There should be at least 24
inches of clearance around the condenser to ensure
adequate airflow to the coil. Secure the condenser/
condensing unit so the system will not move during
operation. Refer to the installation drawing for the
non-charged system weight. It is recommended that
the remote condenser/condensing unit be mounted
with vibration mounts to reduce the amount of vibra-
tion transmitted to the mounting surface.
2.4.3 Controls
NOTE
All thermostats/controls should not be located
near a doorway, supply air register or area
where they would be exposed to direct sunlight
or other false heat sources.
2.4.3.1 A-Tech-1.1/1.2 Programmable Thermostat
WARNING
SATS supplied thermostats/controls do not
contain mercury. Mercury is toxic and may
be hazardous to health. Any replacement
thermostats containing mercury must be
disposed of properly. Contact local authorities
for disposal information.
(BY OTHERS)
Figure 1-
Typical
Installation
Note: Equipment
must be level
to operate
properly.

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Mount the thermostat upright on an inside wall within
the conditioned room that best represents the aver-
age room temperature. In most cases, the thermostat
should be located near the common return air grille.
Mount the thermostat at least 18 inches from an
outside wall and approximately 5 ft. above the floor.
Follow the steps below to mount. Instructions for wir-
ing the unit and setting the dip switches are provided
in Section 2.7, Utility Connections.
1. Unlatch the thermostat from the base. Remove
the cover plate and, using a flat head screw-
driver, gently insert into the latch access slot
(bottom of base) until the lock tab disengages.
2. Pry up the handle of the screwdriver to separate
the thermostat panel from the base. Grip the bot-
tom corners of the thermostat panel to remove
from base.
3. Place the base temporarily over the wire hole
opening in the wall. Level the base and mark
location through the two provided mounting slots.
CAUTION
Do not touch the temperature sensor on the
bottom left corner of the thermostat. The sensor
can be damaged if handled improperly.
4. If using the supplied anchors, drill two 3/16 inch
holes, tap in wall anchors. If only the supplied
screws are being used, drill two 3/32 inch holes.
5. Fasten the base to the wall using the supplied
screws.
6. Reinstall thermostat to base.
2.4.3.2 Humidistat/Dehumidistat (Optional
Supplied with A-Tech-1.1/1.2 Thermostat)
Mounting of the humidistat and dehumidistat is
performed in the same manner. Mount the humidi-
stat and/or dehumidistat (as described in Section
2.4.3.1) to a wall within the conditioned room that
best represents the average humidity of the space. In
most cases, the humidistat and dehumidistat should
be located near the common return air grille. Mount
the humidistat and dehumidistat at least 18” from an
outside wall and approximately 5 ft. above the floor.
Controls may be installed either on a flush switch box
or on a surface switch box. Follow the steps below to
mount. Instructions for wiring of unit are provided in
Section 2.7, Utility Connections.
1. Pull dial knob off, loosen screw (located at bot-
tom of unit) and remove cover.
2. Make wiring connections (see Section 2.7).
3. Mount with the two #6 screws provided.
4. For external setpoint, reinstall cover, tighten
screw, and replace dial knob.
5. For internal setpoint:
a. Turn dial plate to desired setting and tighten
dial lock screw.
b. Break off dial shaft at undercut.
c. Remove insert from cover.
d. Remove protective backing from adhesive on
the blank insert provided and press firmly in
place on cover.
e. Reinstall cover assembly and tighten screw. (If
additional security is required an Allen screw
and wrench are provided.)
f. Remove protective cover from face of cover
insert.
2.4.3.3 Advanced Controller
(E² Microprocessor)
If your unit is equipped with an E² controller, a
separate manual is sent in the unit data package
provided with your unit. The controller display may be
field mounted to a wall within the conditioned space
or it may be located outside the conditioned space
if desired. Refer to the supplemental instructions
provided with the mounting kit when mounting the
controller display. When locating the display panel,
consider the length of wire to be used. As an option,
a 30 foot, 75 foot or 150 foot long cable may be
provided by SATS.
2.4.4 Optional Equipment
NOTE
Do not mount any optional equipment on the
A/C unit’s access panels.
2.4.4.1 Transformer
The buck/boost transformer provided is encapsulated
and can be installed indoors or outdoors. If installed
outdoors, the unit should be installed with the wiring
compartment down to prevent entrance of moisture.
For indoor floor installation the unit may be installed
horizontally for ease of making wire connections.
Each transformer has keyhole mounting slots for
mounting with bolts to desired surface (wall, floor or
other structure capable of supporting its weight).

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2.4.4.2 Condensate Pump (Field Installed)
The condensate pump should be as near to the air
conditioning system as possible. The inlet holes in
the pump must be below the lowest part of drain from
unit. The pump has two mounting supports so it can
be hung on an adjacent wall. Ensure that the pump is
level for proper operation.
2.4.4.3 Non-Fused Service Switch
The non-fused service switch is used to disconnect
main power and isolate the unit during maintenance
and service. The switch has a lockable handle to lock
power out during maintenance periods. The switch is
typically mounted to the A/C cabinet however, it may
be shipped loose for field installation. The case has a
top keyhole slotting mount and two holes in each bot-
tom corner for mounting. The hardware for mounting
the switch is to be field supplied so as to be compat-
ible with the particular mounting surface.
The non-fused service switch can be mounted near
the unit or in a central location. The non-fused ser-
vice switches are rated for either indoor or outdoor
use. Ensure that the proper type for your application
is used.
NOTE
Refer to local and national electrical codes for
the appropriate mounting location.
2.4.5 Remote Sensors
The remote temperature sensor or the tempera-
ture/humidity (T/H) sensor must be located so that it
will properly sense the temperature and/or humidity
conditions to be controlled. The sensor should not be
mounted near a doorway or an area where it would
be exposed to direct sunlight. When locating the sen-
sor, consider the length of wire to be used. As an op-
tion, a 75 foot or 150 foot long cable may be provided
by SATS. Refer to the applicable section that follows
to mount the sensor. For unit wiring details, refer to
Section 2.7, Utility Connections and to the electrical
diagrams provided with the unit.
2.4.5.1 Remote Temperature Sensor (A-Tech 1.1
& A-Tech 1.2)
NOTE
The remote temperature sensor has a maxi-
mum range of 300 feet.
1. Open the sensor case by depressing the button on
the bottom edge of the case until the latch releases.
2. Remove the cover by pulling it out and up at the
bottom.
3. Remove the circuit board from the base by
pulling back the latch that holds it at the center
bottom.
4. Use the base as a template to mark the mounting
holes location on the wall.
5. Using a ¼ inch drill, drill the holes and insert the
provided wall anchors.
6. Run the wires coming out of the wall through the
opening in the base, then secure the base with
the screws provided.
7. Snap the circuit board back into the base. Ensure
that the latch holds the board properly and that
the sensor element is positioned under the holes
in the cover but not touching the cover or base.
8. Make the wiring connections.
9. Replace the cover.
2.4.5.2 Remote Temperature/Humidity Sensor
1. Remove the cover from the base of the sensor by
squeezing it at the top and bottom.
2. Place the base temporarily over the wire hole
opening in the wall. Level the base and mark the
mounting hole locations through the two slots.
3. Drill the mounting holes and insert the provided
wall anchors.
4. Run a 3 conductor shielded cable through the
opening in the base, then secure the base with
screws ensuring the word TOP on the PC board
is oriented upward.
5. Make the wiring connections.
6. Replace the cover plate on the base.
CAUTION
Take care not damage the exposed tempera-
ture/humidity sensors on the PC board while
screwing in the cover fastening screw. The sen-
sors can be damaged if handled improperly.
2.4.5.3 Remote Water Detector
The remote water detector is normally placed in an
auxiliary drain pan located under the
unit. It may be attached using double
sided tape or with the mounting holes
provided in the flanges (one on each
side). Once it’s in place, loosen the
screws provided on the mounting legs
to adjust the height of the sensing probes.

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CAUTION
The probes must not touch the mounting sur-
face. Failure to adhere to this may result in
improper operation of equipment.
2.4.5.4 Cable Type Water Detector
Lay the cable water detector across the surface
where water could
collect. When water is
present, current will
flow between the two
wires.
2.5 Air Distribution Connection
2.5.1 Spot Cooler (See Figure 2)
For units that are not ducted, the air conditioner should
be mounted above the ceiling grid, leaving sufficient
space for the air grilles to rest on the ceiling T-bar.
NOTE
Placement of the grilles is important. The
hinged filter grille goes on the return air side
of the unit. The 3-way directional grille goes
on the conditioned air discharge side of the air
conditioner. Gasketing is factory supplied for
an air seal between the bottom flange of the air
conditioner and the grille. After mounting the air
conditioner, lower the air conditioner until the
gasket meets the grille.
Figure 2- Spot Cooler Grille

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2.5.2 Ducted Systems (See Figure 3)
There are three basic configurations of airflow patterns: 90º/Right Angle, Straight-Thru and In/Out Same-Face.
When determining ducting requirements, always consult your local and state codes. The duct system should be
designed to allow the air to move with as little resistance as possible. Several factors determine ducting material
and size. These factors are predetermined, refer to your ducting system schematic.
The connection of ducting to the unit is typically accomplished with a one-inch duct flange. Supply air outlet and
return air inlet ducts will require a field provided duct flange (refer to the installation drawing provided with the
unit). The connection of ductwork to the unit may be made with either pop rivets or self-tapping screws.
2.6 Piping Connections
2.6.1 Refrigerant
2.6.1.1 Self-Contained Systems
No refrigeration connections are required for self-
contained air, water or glycol-cooled systems (Mod-
els OHS-012/040-AS, OHS-012/120-C and OHS-
012/120-W/G-( )).
2.6.1.2 Split Systems
Split air-cooled systems will require field refrigera-
tion piping. All split systems are shipped with a dry
nitrogen charge of 100 psig.
2.6.1.2.1 Remote Air Cooled Condensers
(AR Models)
Systems utilizing a remote condenser will require a
copper liquid line and discharge line. The piping must
not have a refrigerant line pressure drop over 14 psig
across the condenser and the interconnecting piping
to the condenser sections.
If the condenser is installed above the evaporator,
the discharge line should include a P-trap at the
evaporator.
Figure 3- Ducted System Typical Air Patterns
NOTE
Ensure proper condenser selection to maintain
reasonable sub-cooling temperatures.
If the condenser is installed below the evaporator,
an inverted trap the height of the evaporator coil is
required on the liquid line to help prevent oil and liquid
from flooding back to the compressor during off cycles.
Refer to the Recommended Discharge Line and Rec-
ommended Liquid Line sizing tables on page 2-7.
All refrigeration piping should be installed with high
temperature brazed joints. Use standard refrigeration
practices for piping supports, leak testing, dehydra-
tion and charging of the refrigeration circuits. The
refrigeration piping should be isolated from the build-
ing by the use of vibration isolating supports. Provide
supports (clamps or hangers) as necessary every 5
to 10 feet along piping runs to minimize vibration and
noise transmission. To prevent tube damage when
sealing openings in walls and to reduce vibration
transmission, use a soft flexible material to pack
around the tubes.

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Wrap wet rags around the pipes between the areas
to be soldered and any nearby refrigeration compo-
nents to keep excessive heat from traveling through
the pipe and causing damage.
Clear all pipe connections of debris and prep connec-
tions for soldering. Use only “L” or “K” grade refriger-
ant copper piping. Be careful not to allow solder/pip-
ing debris to get inside refrigerant lines. Silver solder
containing a minimum of 15% silver is recommended.
Dry nitrogen should be flowing through the tubing
while soldering at a rate of not less than 1-2 CFM
(0.028-0.57 M 3/minute).
Refrigerant lines for split systems must be sized
according to the piping distance between the evapo-
rator and the condenser/condensing unit. Each
valve, fitting and bend in the refrigerant line must be
considered in this calculation. Pipe sizes are given
for “equivalent feet”, not linear feet. Do not confuse
the terminologies. For example, a 7/8” standard 90°
elbow has an equivalent length of 1.5 feet; a 7/8”
branch Tee has an equivalent length of 3.5 feet.
These corrections must be accounted for when sizing
your piping. Refer to the following table for standard
equivalent lengths, in feet, of straight pipe.
Oil traps must be included every 20 feet in the verti-
cal risers and the refrigerant lines must be sloped ¼
inch for every 10 feet in the horizontal lines to ensure
proper oil return to the compressor. An inverted
trap is required on the discharge line of the remote
condenser to help prevent oil and liquid from flooding
back to the compressor.
NOTE
In the following 3 tables, the line sizes represent
the correct size for individual refrigeration cir-
cuits. Dual circuit units, (Models 048Dto 120D),
have two separate pairs of refrigeration lines.
One per compressor.
EQUIVALENT LENGTH (FT.) OF STRAIGHT PIPE
OD (In.) Globe Angle 90° 45° Tee Tee
Line Size Valve Valve Elbow Elbow Line Branch
1/2 9.0 5.0 0.9 0.4 0.6 2.0
5/8 12 6.0 1.0 0.5 0.8 2.5
7/8 15 8.0 1.5 0.7 1.0 3.5
1 1/8 22 12 1.8 0.9 1.5 4.5
1 3/8 28 15 2.4 1.2 1.8 6.0
RECOMMENDED DISCHARGE LINE SIZES
*
Equivalent Length Ft.
50’or less 100’or less 150’or less
012 / 12,000 1/2 1/2 5/8
018 / 18,000 5/8 5/8 5/8
024 / 24,000 5/8 7/8 7/8
032 / 32,000 5/8 7/8 7/8
040 / 40,000 7/8 7/8 7/8
048 / 48,000 7/8 7/8 7/8
048D/ 48,000 5/8 7/8 7/8
060 / 60,000 7/8 1-1/8 1-1/8
072D/ 72,000 7/8 7/8 7/8
084D/ 84,000 7/8 7/8 7/8
120D/ 120,000 7/8 1-1/8 1-1/8
*Equivalent Ft. accounts for the linear pipe length as well as equiva-
lent length of Valves, Elbows & Tee’s as shown in the previous table.
Model No. /
Total Unit Capacity
Model No. /
Total Unit Capacity
RECOMMENDED LIQUID LINE SIZES
Condenser to A/C Unit /
Receiver to Evap. (*Equivalent Ft.)
50’or less 100’or less 150’or less
012 / 12,000 3/8 3/8 3/8
018 / 18,000 3/8 3/8 1/2
024 / 24,000 3/8 1/2 1/2
032 / 32,000 1/2 1/2 1/2
040 / 40,000 1/2 5/8 5/8
048 / 48,000 1/2 5/8 5/8
048D/ 48,000 3/8 1/2 1/2
060 / 60,000 1/2 5/8 5/8
072D/ 72,000 1/2 1/2 1/2
084D/ 84,000 1/2 5/8 5/8
120D/ 120,000 1/2 5/8 5/8
CAUTION
Do not exceed the maximum Liquid Line lengths
for the system configurations listed below:
RCU with Hot Gas Bypass.......50 Ft
Remote Condensing Unit ........100 Ft
Remote Air Cooled Condenser 150 Ft

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H = Horizontal Run V = Vertical Run
RECOMMENDED SUCTION LINE SIZES
Model No./ *Equivalent Length Ft.
Total Unit Capacity 50’or less 100’or less
H V H V
012 / 12,000 5/8 5/8 5/8 5/8
018 / 18,000 7/8 7/8 7/8 7/8
024 / 24,000 7/8 7/8 7/8 7/8
032 / 32,000 7/8 7/8 1-1/8 7/8
040 / 40,000 7/8 7/8 1-1/8 1-1/8
048 / 48,000 1-1/8 1-1/8 1-1/8 1-1/8
048D / 48,000 7/8 7/8 7/8 7/8
060 / 60,000 1-1/8 1-1/8 1-1/8 1-1/8
072D / 72,000 7/8 7/8 1-1/8 7/8
084D / 84,000 1-1/8 1-1/8 1-1/8 1-1/8
120D / 120,000 1-1/8 1-1/8 1-1/8 1-1/8
Vertical runs are based on a total rise of 30 equiva-
lent feet. For longer rises, individual calculations
should be made. Sizes assume the use of single
risers; double rises may be necessary.
NOTE
Consult the Copeland applications data guide
for more detailed information regarding refriger-
ant line traps and line sizing.
2.6.1.2.2 Remote Air Cooled Condensing Units
(AHU Models)
Systems utilizing a remote condensing unit (RCU)
will require a copper liquid line and suction line.
When installing remote condensing units above the
evaporator, the suction line should be p-trapped at
the evaporator.
NOTE
Do not exceed 15 feet of vertical distance
when installing the condensing unit below the
evaporator.
When installing remote condensing units below the
evaporator, the suction line should be trapped with
an inverted trap the height of the evaporator coil. This
prevents migration of liquid refrigerant to the com-
pressor during off cycles.
All suction lines must be insulated to prevent conden-
sation from forming on the pipes. Refer to provided
pipe size charts for recommended pipe sizing.
2.6.2 Chilled Water, Water/Glycol and Hot
Water Reheat Piping
The piping connections for water/glycol, chilled water
and systems with hot water reheat are sweat connec-
tions. Pipe sizes may not necessarily be the same
as the unit connection. Piping should be sized to
match the system pressure drop and pump capac-
ity (if applicable) and may require reducing fittings to
match the connection size on the air conditioner. The
recommended ethylene glycol solution ratio is 40%
glycol to 60% water. (SATS recommends Dowtherm
SR1 manufactured by Dow Chemical Co.) Glycol-
cooled systems with a low entering fluid temperature
and all chilled water systems should have insulated
piping.
WARNING
Glycol is hazardous and the manufacturer’s
MSDS should be consulted.
CAUTION
When installing and filling the water/glycol,
chilled water and optional hot water reheat
loop, all air must be bled from the piping
system.
CAUTION
The piping system must be flushed prior to op-
erating the system. Failure to do so will result
in equipment problems.
A strainer should be included in the water/glycol,
chilled water and optional hot water reheat line. Once
the system is operational, the fluid runs through the
strainer where any foreign objects are removed. The
strainer screen should be cleaned periodically.

(Mar, 2012)
CeilAiR OHS Series Installation, Operation & Maintenance Manual
A
ir Technology Systems, Inc.
2-9
2.6.3 Condensate Drain Line
2.6.3.1 Gravity Drain
A 7/8 inch OD copper (sweat type) line is provided
to drain the condensate drain pan. This line also
drains the humidifier, if applicable. The drain line
must be located so it will not be exposed to freezing
temperatures. The drain line should be the full size
of the connection. See the installation drawing
provided with your unit for the size and location of the
condensate drain line.
WARNING
Do not use chloride based water conditioning
additives in the condensate drain pans. This will
cause corrosion to occur on the coil fins.
NOTE
During normal operation the optional humidifier
drains (hot) water into the condensate drain
line. As an option, a separate drain line may
be provided for the humidifier.
2.6.3.2 Condensate Pump (See Figure 4)
A condensate pump is used for automatic removal of
condensate from the air conditioner and flush water
from the humidifier (if applicable). A p-trap must be
installed for proper condensate drainage. The height
of the trap must be a minimum of 2 inches on most
standard systems to ensure proper water drainage
of the drain pan. The condensate pump discharge
line should be 1/2 inch OD maximum copper or vinyl
tubing to prevent excessive back flow to unit.
Figure 4- Condensate Pump
NOTE
Pour some water into the condensate drain(s)
prior to start-up. This fills the trap and prevents
air from being drawn up the drain lines.
2.6.4 Humidifier (Optional)
CeilAiR systems utilize an electrode steam humidifier.
The humidifier empties into the condensate drain
line during the flush/drain cycle. A water supply line
must be connected to the copper tubing connection
supplied by the factory. Refer to the installation
drawing provided with your unit for the size and
location of the connection. The humidifier requires
normal tap water as the water supply. If the supply
water is high in particulate, an external filter may be
needed.
CAUTION
Do not use demineralized water.
Refer to the humidifier operator’s manual, supplied
with the equipment, for complete manufacturer’s
information on the humidifier and the supply water
recommendations.