Stulz CeilAiR Series User manual

CeilAiR Series
Supplemental Air Conditioners
3.5 – 35 kW Systems
Ceiling Mounted, 60 Hz Data
Installation, Operation and Maintenance Manual

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CEILAIR OHS SERIES INSTALLATION, OPERATION AND MAINTENANCE MANUAL
Notice
This document contains information protected by copyright. All rights are reserved. The owner ofthe 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. (STULZ).
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 STULZ.
Unpublished — rights reserved under the copyright laws of the United States and of other countries.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 2017 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
Model Nomenclature
OHSXXXXXXX
System
Nominal Capacity
in 1,000’s of
BTU/H
Configuration Options
OHS = CeilAiR
Overhead System
012, 018, 024, 032,
040, 048, 060, 072,
084, 120
D( ) = Dual Circuit
H( ) = Horizontal Discharge
(“HSeries”)
AHU = Air Handling Unit
AR = Air-Cooled Remote (Split)
AS = Air-Cooled Self-Contained
C = Chilled Water System
G = Glycol-Cooled
W = Water Cooled
AWS = Alternate Water Source
FC = Free Cooling
LP = Low Profile Configuration
SF = Same-Face Air Pattern
SP = Special Configuration*
OHS 040 H G FC
* Please consult factory for additional information.
Example: OHS040HGFC
Overhead System, 40,000 BTU/H Capacity, Horizontal Discharge, Glycol Cooled with optional Free Cooling: OHS040GFC

CEILAIR OHS SERIES INSTALLATION, OPERATION AND MAINTENANCE MANUAL
iii
Contents
1.0 Introduction ................................................. 1
1.1 General ..............................................................................1
1.2 Product Description ......................................................1
1.3 Control Devices...............................................................1
1.4 Safety .................................................................................1
1.4.1 General...............................................................................1
1.4.2 Safety Summary..............................................................2
1.5 General Design................................................................3
1.5.1 Electric Box Access.......................................................3
1.5.2 Coil(s) ..................................................................................4
1.5.3 Blower................................................................................4
1.5.4 Temperature Sensor......................................................4
1.6 Optional Equipment.......................................................4
1.6.1 Humidistat/Dehumidistat............................................4
1.6.2 Temperature/Humidity Sensor..................................5
1.6.3 Heaters ..............................................................................5
1.6.4 Humidifier..........................................................................5
1.6.5 Condensate Pump.........................................................5
1.6.6 Smoke Detector .............................................................5
1.6.7 Firestat ..............................................................................5
1.6.8 Water Detector ...............................................................5
1.7 Free-cooling Operation................................................5
1.8 AWS Operation................................................................7
2.0 Installation ................................................... 8
2.1 Receiving the Equipment.............................................8
2.2 Site Preparation..............................................................8
2.3 Rigging...............................................................................9
2.4 Mounting ...........................................................................9
2.4.1 Indoor Equipment........................................................10
2.4.2 Outdoor Equipment....................................................10
2.4.3 Controls ..........................................................................10
2.4.3.1 ATech Programmable Thermostats.....................10
2.4.3.2 Advanced STULZ E² Controller .............................12
2.4.4 Optional Equipment....................................................12
2.4.4.1 Condensate Pump (Field Installed).......................12
2.4.4.2 Non-Fused Service Switch......................................12
2.4.5 Remote Sensors..........................................................12
2.4.5.1 Remote Temperature Sensor (ATech) ................12
2.4.5.2 Remote Temperature/Humidity Sensor (E²)......13
2.4.6 Humidistat/Dehumidistat (Used with
ATech1.1/1.2 Thermostat) ....................................13
2.4.7 Spot Water Detector ..................................................14
2.4.8 Cable Type Water Detector......................................14
2.5 Air Distribution Connection......................................14
2.5.1 Spot Cooler....................................................................14
2.5.2 Ducted Systems...........................................................14
2.6 Piping Connections ....................................................14
2.6.1 Refrigerant.....................................................................14
2.6.1.1 Self-Contained Systems...........................................14
2.6.1.2 Split Systems ................................................................14
2.6.1.3 Remote Air Cooled Condensers (AR Models)....17
2.6.1.4 Remote Air Cooled Condensing Units
(AHU Models)................................................................17
2.6.2 Chilled Water, Water/Glycol and Hot Water
Reheat Piping...............................................................17
2.6.3 Condensate Drain Line..............................................18
2.6.3.1 Gravity Drain..................................................................18
2.6.3.2 Condensate Pump......................................................18
2.6.4 Humidifier (Optional) ..................................................18
2.7 Utility Connections......................................................18
2.7.1 Main Power....................................................................18
2.7.1.1 Single-Phase Units 208/230V.............................19
2.7.1.2 Single-Phase Units 277V........................................19
2.7.1.3 Three-Phase Units......................................................19
2.7.2 Controls ..........................................................................20
2.7.2.1 ATech 1.1 Programmable Thermostat...............20
2.7.2.2 ATech 1.2 Programmable Thermostat...............20
2.7.3 Air-Cooled Split Systems..........................................20
2.7.3.1 Remote Condenser.....................................................24
2.7.3.2 Remote Condensing Unit .........................................24
2.7.4 Water/Glycol Systems...............................................24
2.7.5 Remote Shut Down ....................................................24
2.7.6 Optional Equipment....................................................24
2.7.6.1 Condensate Pump......................................................24
2.7.6.2 Humidistat/Dehumidistat.........................................24
2.7.6.3 Remote Water Detector............................................25
2.7.6.4 Remote Temperature Sensor (ATech).................25
2.7.6.5 Remote Temperature/Humidity Sensor (E2)......25
2.8 System Charging Procedures.................................25

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CEILAIR OHS SERIES INSTALLATION, OPERATION AND MAINTENANCE MANUAL
2.8.1 Water/Glycol Systems...............................................25
2.8.1.1 Pump ...............................................................................25
2.8.2 DX Unit Charging Requirements............................25
2.8.3 Remote Air-Cooled Systems (AR/AHU)..............26
2.8.4 R407C/R410A Refrigerant ..................................26
2.8.5 Estimating Refrigerant Charge...............................26
2.8.6 Preparing System For Charging.............................27
2.8.6.1 Evacuate the System..................................................27
2.8.7 Refrigerant Charging Procedures .........................28
2.8.7.1 Initial System Charge .................................................28
2.8.7.2 Fine Tuning The System Charge.............................28
2.8.7.3 0 ºF Fan Cycling and -20 ºF Variable Speed
Control.............................................................................29
2.9 Refrigerant Characteristics......................................30
2.9.1 Pressure/Temperature Settings............................30
2.9.2 Saturated Refrigerant Pressure Tables...............30
2.10 System Settings and Adjustments ........................31
2.10.1 Low/High Pressure Limit Switch ..........................31
2.10.2 Head Pressure Controls—Air Cooled
Systems ..........................................................................31
2.10.2.1 Condenser Fan Cycling (Condenser Model
SCSAA, 0 °F)...............................................................31
2.10.2.2 Condenser Multi-Speed Fan Switch (Model
HESCAA , 0 °F ) .........................................................31
2.10.2.3 Variable Condenser Fan Speed (Condenser
Model SCSSA, -20 °F).............................................31
2.10.2.4 Intelligent Control (Condenser Model SCSEC
Only, -20 °F)..................................................................31
2.10.2.5 Flooded Head Pressure Control (Condenser
Model SCSAA With Fan Cycling, -30 °F) ..........32
2.10.2.6 Flooded Head Pressure Control (Condenser
Model HESCAA , -30 °F) .......................................32
2.10.3 Head Pressure Controls—Water/Glycol Cooled
Systems ..........................................................................32
2.10.4 Humidifier Adjustment...............................................32
2.10.5 Blower Adjustment .....................................................33
2.10.5.1 Belt Drive Blower.........................................................33
2.10.5.2 EC Fan (Optional).........................................................33
2.10.6 Thermal Expansion Valve..........................................33
2.10.7 Hot Gas Reheat (Optional)........................................34
2.10.8 Hot Gas Bypass (Optional).......................................34
2.10.8.1 Snap Acting Hot Gas Bypass .................................34
2.10.8.2 Full Floating Hot Gas Bypass..................................34
3.0 Commissioning, Operation And Decommis-
sioning ........................................................ 35
3.1 Commissioning the Unit ............................................35
3.1.1 Commissioning Steps................................................35
3.2 Operating the Unit.......................................................36
3.2.1 Shutdown Procedure.................................................36
3.2.2 Start-up Procedure ....................................................36
3.3 Programming the Thermostat.................................36
3.3.1 ATech Controller.........................................................36
3.3.2 E² Controller..................................................................36
3.4 Decommissioning the Unit.......................................36
3.4.1 Recovering Refrigerant.............................................37
3.4.2 Labeling Decommissioned Equipment................37
4.0 Maintenance............................................... 37
4.1 Periodic General Maintenance ...............................37
4.1.1 A/C Unit..........................................................................38
4.1.1.1 Compressor...................................................................38
4.1.1.2 Heater..............................................................................38
4.1.1.3 Air Filters ........................................................................38
4.1.1.4 Blower.............................................................................38
4.1.1.5 Coils .................................................................................38
4.1.1.6 Drain Pan........................................................................38
4.1.1.7 Condensate Pump .....................................................39
4.1.1.8 Humidifier.......................................................................39
4.1.2 Condenser/Condensing Unit..................................39
4.2 Troubleshooting...........................................................40
4.3 Field Service..................................................................43
4.3.1 Leak Detection.............................................................43
4.3.2 Leak Repair...................................................................43
4.3.3 Refrigerant Piping.......................................................43
4.3.4 General Common Repairs/Component
Replacement.................................................................43
4.3.4.1 Compressor Failure ...................................................43
4.3.4.2 Standard Cleanout Procedure................................44
4.3.4.3 Burn-Out/Acidic Cleanup Procedure ..................44
4.3.4.4 Humidifier Cylinder Replacement..........................44
4.3.4.5 Air Filter Replacement...............................................45
5.0 Product Support ........................................ 45
5.1 Factory Authorized Start Up/Warranty
Inspection ......................................................................45
5.2 Technical Support .......................................................45

CEILAIR OHS SERIES INSTALLATION, OPERATION AND MAINTENANCE MANUAL
v
Figures
Figure 1. ATech Digital Thermostats.................................1
Figure 2. E2Microprocessor Controller and Display ....1
Figure 3. CeilAiR OHS032AR (Access Panels Re-
moved) ........................................................................4
Figure 4. Free Cooling Diagram............................................6
Figure 5. Alternate Water Source Diagram ......................7
Figure 6. Typical Installation ..................................................9
Figure 7. ATech Controller Installation...........................10
Figure 8. Spot Cooler Grille.................................................11
Figure 9. Ducted System Typical Air Patterns ..............11
Figure 10. Temperature Sensor for ATech ......................12
Figure 11. Temperature/Humidity Sensor for E2
Controller................................................................13
Figure 12. Condensate Pump...............................................18
Figure 13. Sample Nameplate..............................................19
Figure 14. ATech 1.1 (top) and 1.2 (bottom) Controller
Wiring Contacts....................................................20
Figure 15. ATech 1.1 Control Wiring.................................21
Figure 16. ATech 1.2 Control Wiring.................................21
Figure 17. Interconnection Field Wiring Remote Con-
denser......................................................................22
Figure 18. Interconnection Field Wiring Remote Con-
densing Unit...........................................................22
Figure 19. Interconnection Field Wiring Remote Con-
densing Unit with Dual Compressors............23
Figure 20. Interconnection Field Wiring Glycol
Systems...................................................................23
Figure 21. Belt Drive Blower ................................................33
Tables
Table 1. Pipe Equivalent Lengths....................................15
Table 2. Recommended Discharge Line Sizes For
R407C Refrigerant.............................................15
Table 3. Recommended Discharge Line Sizes For
R410A Refrigerant .............................................15
Table 4. Recommended Liquid Line Sizes For R407C
Refrigerant (Condenser to Receiver )............16
Table 5. Recommended Liquid Line Sizes For R410A
Refrigerant (Condenser to Receiver) ............16
Table 6. Recommended Suction Line Sizes For R407C
Refrigerant ............................................................16
Table 7. Recommended Suction Line Sizes For R410A
Refrigerant.............................................................16
Table 8. Weight (lb) of Refrigerant per 100 ft of Type L
Tubing.......................................................................26
Table 9. Weight (lb) of Refrigerant by OHS Model ....27
Table 10. Refrigerant Pressure/Temperature
Settings ...................................................................30
Table 11. Saturated Refrigerant Pressure......................30
Table 12. Troubleshooting Table ........................................40
5.3 Obtaining Warranty Parts .........................................46
5.4 Obtaining Spare/Replacement Parts ..................46
Appendix A - OHS Preventive Maintenance
Inspection Checklist.................................. 47
Appendix B - Acronyms and Abbreviations............... 50

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CEILAIR OHS SERIES INSTALLATION, OPERATION AND MAINTENANCE MANUAL

CEILAIR OHS SERIES INSTALLATION, OPERATION AND MAINTENANCE MANUAL
1
1.0 INTRODUCTION
1.1 General
The CeilAiR®ceiling-mounted air conditioning system
documented in this manual is designed and manufactured
by STULZ Air Technology Systems, Inc. (STULZ).
STULZ CeilAiR overhead air conditioning systems (OHS)
are constructed using the finest available materials/com-
ponents, state-of-the-art technology and quality crafts-
manship. The unit will provide years of trouble free service
if installed and maintained in accordance with this manual.
Damage to the unit from improper installation, operation
or maintenance is not covered by the warranty. Due to
advances in technology, components described herein are
subject to change without notice.
All STULZ CeilAiR OHS systems and CyberAiR centrifugal
condensers are designed to be installed indoors, unless
otherwise noted on the equipment. Propeller-type con-
densers, condensing units, drycoolers and pump packages
are designed for outdoor use.
1.2 Product Description
STULZ CeilAiR OHS systems are designed to be the most
versatile and flexible ceiling-mounted air conditioning
systems in the industry. The unit is available in air-cooled,
water-cooled, glycol-cooled and chilled-water configura-
tions. The cooling capacity in BTU/H will depend on the
unit size, which can range from 1 to 10 tons (3.5–35 kW),
and can be either a single stage or dual stage unit.
In addition to cooling, other functional modes of opera-
tion include heating, humidification, dehumidification and
filtration to provide complete environmental control of a
conditioned space. The cabinet configuration is available in
a 2 ft x 4 ft frame for units ranging from 12,000 to 40,000
BTU/H (spot cooler or ducted) or a larger frame for units
ranging from 48,000 to 120,000 BTU/H (ducted only).
For ducted units, there are three basic configurations of
airflow patterns: 90º/right angle, straight-through and in/
out-same-face (see Figure 9 on page 11). Refer to the
installation drawing provided with the unit for the type of
cabinet configuration and for the layout dimensions.
1.3 Control Devices
STULZ offers a variety of control devices for CeilAiR OHS
series systems. Control interfaces are typically remotely
mounted to a wall or control panel.
The default control device for OHS units is the ATech
digital thermostat, which provides basic control of the
system. Slightly different wiring is used with the thermostat
in single- and dual-stage units, as shown in Figure 14 on
page 20. The single-stage version is the ATech 1.1.
The two-stage version is the ATech 1.2. An operating
manual for the thermostat is provided with the unit under
separate cover.
Figure 1. ATech Digital Thermostats
The advanced STULZ E² microprocessor controller is
also available for OHS systems. This controller 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 dehumidification and remote
communication with building management systems. An
operating manual for the controller is provided with the unit
under separate cover.
Figure 2. E2Microprocessor Controller and Display
1.4 Safety
1.4.1 General
STULZ Air Technology Systems, Inc. uses notes, cautions
and warnings in its manuals to draw attention to important
operating and safety information.
A bold text NOTE alerts you to an important detail.
A bold text CAUTION provides information that is impor-
tant for protecting your equipment and performance. Be
especially careful to read and follow all cautions that apply
to your application.

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CEILAIR OHS SERIES INSTALLATION, OPERATION AND MAINTENANCE MANUAL
A bold text WARNING provides information important for
protecting you from harm. Pay very close attention to all
warnings that apply to your application.
precedes a general WARNING or CAUTION safety
statement.
precedes an electrical shock hazard WARNING or
CAUTION safety statement.
1.4.2 Safety Summary
The following warnings and cautions appear in this manual.
Before performing any installation, operation, maintenance
or troubleshooting procedure, read and understand all
relevant cautions and warnings. Maintenance and/or repair
procedures must be performed by a journeyman refrigera-
tion mechanic or air conditioning technician.
WARNING
Never work on electrical equipment unless another
person who isfamiliarwith the operation and hazards
of the equipment and competent in administering
first aid is nearby.
WARNING
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.
WARNING
When working on electrical equipment, remove all
jewelry, watches, rings, etc.
WARNING 1
Hazardous voltage will still be present inside the
electric box at the motor starter protectors and
circuit breakers, even with the unit turned off at the
E2controller. To isolate the unit for maintenance,
turn offpowerat the main power disconnect switch.
Always disconnect main power prior to performing
any service or repairs.
WARNING
Alock-out/tag-out procedure should befollowedto
ensurethat power is not inadvertently reconnected.
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 teststhat require power.With power
and controls energized,the unit could begin operat-
ing at any time.
WARNING
Never lift any component in excess of 35 lb without
help. If a lifting device is used to move a unit, ensure
it is capable of supporting the wight of the unit.
WARNING
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.
WARNING
Neveroperate the unitwith any cover, guard, screen
panel, etc., removed unlessthe instructions specifi-
cally state otherwise, then do so with extreme cau-
tion to avoid personal injury.
WARNING
Refrigerant is used with this equipment. Death or
serious injury may result if personnel fail to observe
proper safety precautions. Great care must be ex-
ercised to prevent contact of liquid refrigerant or
refrigerant gas, discharged underpressure,with any
part ofthe body.The extremelylowtemperature re-
sulting from the rapid expansion ofliquid refrigerant
orpressurized gascan cause sudden andirreversible
tissue damage.
At a minimum, all personnel should wear thermal
protective gloves and face-shield/goggles when
working with refrigerant. Application of excessive
heat to any componentwill cause extreme pressure
and may result in a rupture.
Exposure of refrigerant to an open flame or a very
hot surface may cause a chemical reaction that
forms hydrofluoric acid orcarbonyl fluoride, a highly
poisonous and corrosive gas commonly referred to
as fluorophosgene. In its natural state, refrigerant is
a colorless, odorless vapor with no toxic character-

CEILAIR OHS SERIES INSTALLATION, OPERATION AND MAINTENANCE MANUAL
3
istics. 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 reviewthe manufacturer’s Safety DataSheet
(SDS) provided withthe unit before performing work
involving refrigerant.
WARNING
Do not use cleaning solvents near open flame or
excessive heat. Wear eye protection when blow-
ing 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.
WARNING
Certain maintenance or cleaning procedures may
call for the use and handling of chemicals, solvents,
or cleansers. Always refer to the manufacturer’s
Safety Data Sheet (SDS) prior to using these ma-
terials. Clean parts in a well-ventilated area. Avoid
inhalation ofsolvent fumes and prolonged exposure
of skin to cleaning solvents. Wash exposed skin
thoroughly after contact with solvents.
WARNING
When performing soldering or desoldering
operations, 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.
WARNING
Cooling coils (and associated piping circuits) are
pressurized (up to 100 psi) and sealed when they
leavethe factory. Before installingthe interconnect-
ing piping, observe appropriate safety precautions
and releasethe pressure via an available stem valve
or Schrader valve prior to uncapping the pipes.
CAUTION
When the air conditioner operates in cooling mode
the return air intake and discharge (supply) must be
free of obstructions. Ensure panels are secure and
latched into position.
CAUTION
After interconnecting piping is installed, the piping
system must be cleaned. If solvents/cleaning solu-
tions are used, ensure they are completely flushed
from the piping before connecting it to the unit.
Failure to do so will result in equipment problems.
CAUTION
When installing and filling a chilled water or water/
glycol loop, all air must be bled from the piping
system.
CAUTION
Do not use chloride-based water conditioning ad-
ditives in the condensate drain pans. They cause
corrosion to occur on the coil fins.
CAUTION
When transporting and installing theA/C unit, it must
be kept in its normal, horizontally-installed position.
Ifthe unit is not kept level and horizontal, damage to
the compressor(s) will result.
1.5 General Design
The CeilAiR unit is housed in an aluminum frame cabinet
and is rated for indoor use. Removable panels are located
on the front and rear ofthe 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 electric box inside the
cabinet with a removable panel for accessing the electri-
cal components. Operator controls may be conveniently
located on a wall within the space to be conditioned.
NOTE
Customer specified, non-standard features or de-
sign variations may not be described in this manual.
Referto the installation and electrical drawings sup-
plied withyourunit fordetails on additional feature(s).
In some cases, an addendum tothis manual mayalso
be included to further describe the feature(s).
1.5.1 Electric Box Access
Electrical components are protected in an enclosure
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 E2
controller (if present) and shuts the unit off.

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CEILAIR OHS SERIES INSTALLATION, OPERATION AND MAINTENANCE MANUAL
1.5.2 Coil(s)
The cooling and optional hot water reheating coils are alu-
minum finned/copper tube construction. The coils are leak
tested and cleaned before installation at the factory.
1.5.3 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 stati-
cally balanced to minimize vibration. 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 con-
figured 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-driv-
en 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 21 on page 33).
1.5.4 Temperature Sensor
As a standard for systems utilizing a wall mounted ATech
thermostat, the temperature sensor is built into the thermo-
stat for room air control. The sensor monitors the room air
conditions and provides input signal(s) to the thermostat.
The thermostat manages the operation ofthe A/C unit
consistent with the setpoints 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.
1.6 Optional Equipment
1.6.1 Humidistat/Dehumidistat
As an option for systems employing 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 its operation. The humidistat controls
the humidifier’s operation independently of the control
thermostat; however, the blower must be on for the humidi-
fier 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
Figure 3. CeilAiR OHS032AR (Access Panels Removed)