American Standard YSC036A Owner's manual

RT-SVX21C-EN
Library Service Literature
Product Section Unitary
Product Rooftop AC – Lt. Comm. SZ
Model Y_
Literature Type Installation/ Oper/ Maint
Sequence B
Date March 2006
FileNo. SV-UN-RT-SVX21C-EN 12/05
Supersedes Y_C-IOM-1D 12/04; RT-SVX21B-EN 12/05
Since the manufacturer has a policy of continuous product improve-
ment, it reserves the right to change specifications and design without
notice. The installation and servicing of the equipment referred to in
this booklet should be done by qualified, experienced technicians.
© American Standard 2005
Models:
YSC036A - YSC120A
YHC033A - YHC120A
YSC036E - YSC060E
INSTALLATION
OPERATION
MAINTENANCE
Customer Property — Contains wiring, ser-
vice, and operation information. Please retain.
Packaged Gas/Electric
3 Through 10 Ton
IMPORTANT NOTE: All phases of this installation must comply with the NATIONAL, STATE & LOCAL CODES. In
addition to local codes, the installation must conform with National Electric Code -ANSI/NFPA NO. 70 LATEST
REVISION and NFPA 90 STANDARD LATEST REVISION for the installation of Air Conditioning and Ventilating
Systems.
CLICK ANYWHERE on THIS PAGE to RETURN to AMERICAN STANDARD HVAC
AGE & MANUALS at InspectApedia.com

2
Table of Contents
General Information
Literature Change History ............. 3
Overview of Manual....................... 3
Model Number Description ........... 3
Unit Nomenclature ........................ 4
Electro Mechanical Control ........... 5
Supply Fan Failure Input (Optional)5
Clogged Filter Switch (Optional) ... 6
Compressor Disable (CPR1/2) ..... 6
ReliaTel Control............................. 6
Electromechanical Control ............ 6
High Pressure Control (Optional).. 6
ReliaTel Control............................. 6
Electromechanical Control ............ 6
Power Exhaust Control (Optional). 6
Lead/Lag Control........................... 6
(ZSM) (BAYSENS006B) ............... 6
(ZSM) (BAYSENS008B) ............... 6
(BAYSENS010B) ........................... 6
Wall Mounted Relative Humidity
Sensor (BAYSENS036A).............. 6
Duct Mounted Relative Humidity
Sensor (BAYSENS037A)............. 6
Programmable Zone Sensor -
(BAYSENS019B) ........................... 7
Remote Zone Sensor
(BAYSENS013B) ........................... 7
Remote Zone Sensor
(BAYSENS014B) ........................... 7
Remote Zone Sensor
(BAYSENS016A) ........................... 7
Remote Zone Sensor
(BAYSENS017B) ........................... 7
Electro Mechanical Control ........... 7
BAYSENS025A.............................. 7
High Temperature Sensor
(BAYFRST001A)............................ 7
Evaporator Frost Control ............... 7
(ReliaTel™ Option) ........................ 7
(Electro Mechanical Option).......... 7
Pre-Installation Checklist
Smoke Detector Sensor ................ 8
Phase Monitor ............................... 8
ReliaTel Control Only .................... 8
Precautionary Measures ............... 9
Unit Clearances
..................................................... 10
Unit Dimensions
..................................................... 11
..................................................... 12
Installation
Rigging and
Center-of-Gravity Data ................ 14
Foundation .................................. 15
Horizontal Units ........................... 15
Downflow Unit Supply &
Return Air Openings.................... 15
Downflow Unit Supply &
Return Air Openings ................... 15
Installation ................................... 16
Downflow..................................... 16
Factory Installed Economizer ...... 17
Temperature Limit Switch
Usage for Gas Heat Units............17
IHorizontal
Discharge Conversion ................ 18
TCO-A Instructions:...................... 18
ITCO-A Instructions:..................... 19
Return Air Smoke Detector.......... 20
Through the Base Gas Installation21
Requirements for Gas Heat.........21
Condensate Drain Configuration 22
Filter Installation .......................... 22
Standard Wiring........................... 23
Optional TBUE Wiring..................23
Field Installed Control Wiring ...... 23
Control Power Transformer ..........23
Controls using 24 VAC ................ 24
24V AC Conductors with
Reliatel........................................ 24
24V AC Conductors with
Electromechanical Unit ............... 24
Controls using DC Analog
Input/Outputs............................... 24
(Standard Low Voltage
Multiconductor Wire)................... 24
(Dehumidification Option) ........... 25
Electro Mechanical Control ......... 26
Customer Low Voltage Routing- . 26
ReliaTel Control .......................... 26
Customer Low Voltage Routing- . 26
Smoke Detector ........................... 27
Customer Low Voltage Wiring- .... 27
Space Temperature Averaging.... 28
Sizing Natural Gas Pipe
Mains & Branches ....................... 30
Pre-start
Voltage Imbalance....................... 31
Electrical Phasing........................ 31
Compressor Crankcase Heaters. 31
Electro Mechanical Controls ....... 33
Electrocmechanical Controls ...... 33
Fan Test and Minimum Ventilation 33
Economizer Cooling.................... 33
(Units with Direct Drive Indoor Fan)33
ReliaTel Control........................... 33
(Units with Belt Drive Indoor Fan) 34
Start-Up
Compressor Start-Up................... 35
Scroll Compressors ..................... 35
Dehumidification Option.............. 35
Gas Heat Units ............................ 36
Final System Setup...................... 36
Maintenance
Fan Belt Adjustment -
Belt Drive Units ............................ 37
Belt Tension Gauge ..................... 37
Filters ........................................... 38
Return Air Smoke Detector
Maintenance................................ 38
Cooling Season........................... 38
Heating Season........................... 38
Dehumidification Option.............. 40
Annual Maintenance ................... 40
Final Process ............................... 40
Sample Maintenance Log ...........40
Trouble Shooting
ReliaTel Control........................... 41
System Status
Checkout Procedure ................... 41
System Failure ............................. 41
Heating Failure ............................ 41
Trouble Shooting ......................... 42
Cooling Failure ............................ 42
Service Failure ............................. 42
Simultaneous
Heat and Cool Failure ................ 42
Cool Failure ................................. 42
Resetting
Cooling and Ignition Lockouts ....42
(ZTS) Service Indicator ................ 42
Fan Failure Switch ....................... 43
(ZTEMP)....................................... 43
Cooling Set Point (CSP)
and Heating Set Point (HSP) ....... 43
Relative Humidity Sensor Test .... 43
Testing serial
communication voltage .............. 43
ReliaTel Refrigeration
Module (RTRM) Default Chart.... 44
Unit Economizer Control
(ECA) Troubleshooting ................ 44
ReliaTel Control........................... 44
Electro Mechanical Control ......... 44
Cooling Failure ............................ 45
Resetting Cooling and
Ignition Lockouts ......................... 45
Unit Economizer Control (ECA)
Test Procedures........................... 45
Electro Mechanical Control ......... 45
Testing the ECA
resistors and sensors ..................45

3
Literature Change History
Y_C-IOM-1C (December 2004)
Added capacitor discharge warning.
Y_C-IOM-1D (March 2004)
Added Phase Monitor option
Y_C-IOM-1C (April 2003)
Dehunidification Option added
Y_C-IOM-1C (April 2002)
Corrected TC01Tripping values, page 15.
Y_C-IOM-1B (March 2002)
Added Supply Air Tubing and Smoke Detector informa-
tion.
Y_C-IOM-1A (October 2001)
Added 6 1/4 through 10 Ton models to product offering.
Overview of Manual
Note: One copy of this document ships inside the
control panel of each unit and is customer
property. It must be retained by the unit’s
maintenance personnel.
This booklet describes proper installation, operation, and
maintenance procedures for air cooled systems. By care-
fully reviewing the information within this manual and fol-
lowing the instructions, the risk of improper operation
and/or component damage will be minimized.
It is important that periodic maintenance be performed to
help assure trouble free operation. A maintenance sched-
ule is provided at the end of this manual. Should equip-
ment failure occur, contact a qualified service organiza-
tion with qualified, experienced HVAC technicians to
properly diagnose and repair this equipment.
NOTICE:
Warnings and Cautions appear at appropriate sections
throughout this manual. Read these carefully.
WARNING– Indicates a potentially hazardous
situation which, if not avoided, could result in death or
serious injury.
CAUTION – Indicates a potentially hazardous
situation which, if not avoided, may result in minor or
moderate injury. It may also be used to alert against
unsafe practices.
CAUTION – Indicates a situation that may result in
equipment or property-damage-only accidents.
General Information
Model Number Description
All products are identified by a multiple-character model
number that precisely identifies a particular type of unit. An
explanation of the alphanumeric identification code is pro-
vided below. Its use will enable the owner/operator, install-
ing contractors, and service engineers to define the opera-
tion, specific components, and other options for any specific
unit.
When ordering replacement parts or requesting service, be
sure to refer to the specific model number and serial num-
ber printed on the unit nameplate.
WARNING
Contains Refrigerant!
System contains oil and refrigerant under high pressure.
Recover refrigerant to relieve pressure before opening
the system. See unit nameplate for refrigerant type. Do
not use non-approved refrigerants, refrigerant substi-
tutes, or refrigerant additives.
Failure to follow proper procedures or the use of non-ap-
proved refrigerants, refrigerant substitutes, or refriger-
ant additives could result in death or serious injury or
equipment damage.
WARNING
Hazardous Voltage w/Capacitors!
Disconnect all electric power,including remote discon-
nects and discharge all motor start/run capacitors be-
fore servicing. Follow proper lockout/tagout procedures
to ensure the power cannot be inadvertently energized.
Verify with an appropriate voltmeter that all capacitors
have discharged. Failure to disconnect power and dis-
charge capacitors before servicing could result in death
or serious injury.
Note: For additional information regarding the safe dis-
charge of capacitors, see PROD-SVB06A-EN or PROD-
SVB06A-FR
CAUTION
Equipment Damage From Ultraviolet (UV)
Lights!
The manufacturer does not recommend field installation
of ultraviolet lights in its equipment for the intended pur-
pose of improving indoor air quality.High intensity C-
band ultraviolet light is known to severely damage poly-
mer (plastic) materials and poses a personal safety risk
to anyone exposed to the light without proper personal
protective equipment. Polymer materials commonly
found in HVAC equipment that may be susceptible in-
clude insulation on electrical wiring, fan belts, thermal in-
sulation, various fasteners and bushings. Degradation of
these materials can result in serious damage to the
equipment.
The manufacturer accepts no responsibility for the
performance or operation of our equipment in which
ultraviolet devices were installed outside of the
manufacturer’s factory or its approved suppliers.

4
General Information
Unit Nomenclature
Digit 1 - ProductType
Y = Packaged Gas/Elect
Digit 2 - Unit Efficiency Level
S = Standard
H = High
Digit 3 - Airflow Configuration
C = Convertible
Digit 4, 5, 6 - Cooling Capacity (MBH)
033 = 3 Ton
036 = 3 Ton
043 = 4 Ton
048 = 4 Ton
060 = 5 Ton
063 = 5 Ton
072 = 6 1/4 Ton
090 = 7 1/2 Ton (Single
Commpressor)
092 = 7 1/2 Ton (Dual Compressor)
102 = 8 1/2 Ton
120 = 10 Ton
Digit 7 - Major Design Sequence
A = First
E = R410A
Digit 8 - Electrical Characteristics
1 = 208-230/60/1
3 = 208-230/60/3
4 = 460/60/3
D = 380-415/50/3
K = 380/60/3
T = 200/50/3
W = 575/60/3
Digit 9 - Unit Control
R = Relia Tel
E = Electro-mechanical
Digit 10 - Heat Capacity
H = High
M = Medium
L = Low
X = Low, Stainless Steel Heat Exchanger
Y = Medium, Stainless Steel Heat
Exchanger
Z = High, Stainless Steel Heat Exchanger
Digit 11 - Minor Design Sequence
Digit 12, 13 - Service Digit Sequence
Digit 14 - Factory Installed Options
-Fresh Air Section
0 = No Fresh Air
A = Manual OA, 0 - 25%
B = Motorized OA, 0 - 50%
C = Economizer Dry Bulb
D = Economizer with
Barometric Relief
E = Economizer, Reference Enthalpy
F = Economizer, Reference Enthalpy,
with Barometric Relief
G = Economizer Comparative En-
thalpy
H = Economizer, Comparative En-
thalpy, with Barometric Relief
Digit 15 - Factory Installed Options
-Supply Fan
0 = Standard Drive
1 = Oversize Motor
2 = Option Belt Drive
Digit 16 - Factory Installed Options
-Hinged Service Access
0 = Standard Panels/Standard Filters
A= Hinged AccessPanels/Standard
Filters
B= StandardPanels/2” PleatedFilters
C = Hinged Access Panels/2” Pleated
Filters
Digit 17 - Factory Installed Options
-Condenser Coil Protection
0 = Standard
1 = Hail Guard
2 = Epoxy Coated Condenser Coil
3 = Epoxy Coated Condenser Coil
and Hail Guard
4 = CompleteCoat Condenser Coil
5 = CompleteCoat Condenser Coil and
Hail Guard
Digit 18 - Factory Installed Options
-ThroughThe Base
0 = Without Through The Base
Connection
A = Through The Base Electrical
Connection
B = Through The Base Gas
Connection
C = Through The Base Electrical and
Gas Connection
Digit 19 - Factory Installed Options
-Disconnect Switch/Circuit Breaker
0 = Without Disconnect Switch/Circuit
Breaker/Phase Monitor
1 = Unit Mounted Non-Fused
Disconnect Switch
2 = Unit Mounted Circuit Breaker
3 = Unit Mounted Phase Monitor
4 = Unit Mounted Phase Monitor and
Unit Mounted Non-Fused
DisconnectSwitch
5= UnitMountedPhase Monitorand
UnitMounted CircuitBreaker
Digit 20 - Factory Installed Options
-Convenience Outlet
0 = Without Convenience Outlet
A = Convenience Outlet Unpowered
B = Convenience Outlet Powered
Digit 21 - Factory Installed Options
-Communications
0 = Without Communications Options
1 = Trane Communications Interface
2 = Lontalk Communications Interface
3 = Novar Communications Interface
Digit 22 - Factory Installed Options
-Refrigeration System
0 = Without Refrigeration System Op-
tion
A = Expansion Valve
B = Dehumidification Option
Digit 23 - Factory Installed Options
-Refrigeration Controls
0 = Without Refrigeration Controls
1 = High Pressure Control
2= FrostatTM
3 = Crankcase Heater
4 = High Pressure Control and Frostat
5 = High Pressure Control and
Crankcase Heater
6 = Frostat and Crankcase Heater
7 = High Pressure Control, Frostat and
Crankcase Heater
Digit 24 - Factory Installed Options
-Smoke Detector
0 = Without Smoke Detector
A = Return Air Smoke Detector
B = Supply Air Smoke Detector
C = Return and Supply Air Smoke
Detector
Digit 25 - Factory Installed Options
-System Monitoring Controls
0 = Without Monitoring Controls
1 = Clogged Filter Switch
2 = Fan Failure Switch
3 = Discharge Air Sensing Tube
4 = Clogged Filter Switch and Fan
Failure Switch
5 = Clogged Filter Switch and
Discharge Air Sensing Tube
6 = Fan Failure Switch and
Discharge Air Sensing Tube
7 = Clogged Filter Switch, Fan Failure
Switch and
Discharge Air Sensing Tube
8 = Novar Return Air Sensor

5
General Information
Unit Nameplate
A Mylar unit nameplate is located on the unit’s corner sup-
port next to the filter access panel. It includes the unit model
number, serial number, electrical characteristics, refrigerant
charge, as well as other pertinent unit data.
Compressor Nameplate
The nameplate for the compressors are located on the side
of the compressor.
Unit Description
Before shipment, each unit is leak tested, dehydrated,
charged with refrigerant and compressor oil, and run tested
for proper control operation.
The condenser coils are aluminum fin, mechanically
bonded to copper tubing.
Direct-drive, vertical discharge condenser fans are provided
with built-in thermal overload protection.
There are two control systems offered for these units.
The electro mechanical control option uses a thermostat to
perform unit functions.
The ReliaTel™ Control Module is a microelectronic control
system that is referred to as “Refrigeration Module” (RTRM).
The acronym RTRM is used extensively throughout this
document when referring to the control system network.
These modules through Proportional/Integral control algo-
rithms perform specific unit functions that governs unit op-
eration in response to; zone temperature, supply air tem-
perature, and/or humidity conditions depending on the ap-
plication. The stages of capacity control for these units are
achieved by starting and stopping the compressors.
The RTRM is mounted in the control panel and is factory
wired to the respective internal components. The RTRM re-
ceives and interprets information from other unit modules,
sensors, remote panels, and customer binary contacts to
satisfy the applicable request for cooling.
Economizer Control Actuator (Optional)
Electro Mechanical Control
The ECA monitors the mixed air temperature, ambient dry
bulb temperature and local minimum position setpoint sen-
sors, if selected, to control dampers to an accuracy of +/- 5%
of stroke. The actuator is spring returned to the closed posi-
tion any time that power is lost to the unit. It is capable of de-
livering up to 25 inch pounds of torque and is powered by
24VAC.
ReliaTel™ Control
The ECA monitors the mixed air temperature, return air tem-
perature, minimum position setpoint (local or remote),
power exhaust setpoint, CO2 setpoint, CO2, and ambient
dry bulb/enthalpy sensor or comparative humidity (return air
humidity against ambient humidity) sensors, if selected, to
control dampers to an accuracy of +/- 5% of stroke. The ac-
tuator is spring returned to the closed position any time that
power is lost to the unit. It is capable of delivering up to 25
inch pounds of torque and is powered by 24 VAC.
RTCI - ReliaTel™ Trane Communication
Interface (Optional)
This module is used when the application calls for an ICSTM
building management type control system. It allows the con-
trol and monitoring of the system through an ICS panel. The
module can be ordered from the factory or ordered as a kit
to be field installed. Follow the installation instruction that
ships with each kit when field installation is necessary.
RLCI - ReliaTel™ LonTalk Communication
Interface (Optional)
This module is used when the application calls for an ICSTM
building management type control system that is LonTalk. It
allows the control and monitoring of the system through an
ICS panel. The module can be ordered from the factory or
ordered as a kit to be field installed. Follow the installation
instruction that ships with each kit when field installation is
necessary.
RTOM - ReliaTel™ Options Module (Optional)
The RTOM monitors the supply fan proving, clogged filter,
supply air temperature, exhaust fan setpoint, supply air tem-
pering, Frostat™ and smoke detector. Refer to system input
devices and functions for operation.
System Input Devices & Functions
The RTRM must have a zone sensor or thermostat input in
order to operate the unit. The flexibility of having several
mode capabilities depends upon the type of zone sensor or
thermostat selected to interface with the RTRM.
The descriptions of the following basic Input Devices used
within the RTRM network are to acquaint the operator with
their function as they interface with the various modules.
Refer to the unit’s electrical schematic for the specific mod-
ule connections.
The following controls are available from the factory for field
installation.
Supply Fan Failure Input (Optional)
The Fan Failure Switch can be connected to sense indoor
fan operation:
FFS (Fan Failure Switch) If air flow through the unit is not
proven by the differential pressure switch connected to the
RTOM (factory set point 0.07 “ w.c.) within 40 seconds nomi-
nally, the RTRM will shut off all mechanical operations, lock
the system out, send a diagnostic to ICS, and the SERVICE
output will flash. The system will remain locked out until a
reset is initiated either manually or through ICS.

6
General Information
Clogged Filter Switch (Optional)
Theunit mountedcloggedfilter switchmonitorsthe pressure
differentialacrossthereturnairfilters.Itismountedinthe filter
sectionand isconnectedto theRTOM. Adiagnostic SER-
VICEsignal issentto theremote panelif thepressure differen-
tialacrossthe filtersisatleast0.5"w.c.Thecontactswill auto-
maticallyopenwhen thepressuredifferential acrossthefilters
decreasesto approximately 0.4"w.c. Theclogged filteroutput
isenergized when thesupply fanis operatingandthe clogged
filterswitch hasbeen closedfor atleast2 minutes.The system
willcontinue tooperateregardless ofthestatus ofthefilter
switch.
Compressor Disable (CPR1/2)
This input incorporates the low pressure control (LPC) of
each refrigeration circuit and can be activated by opening a
field supplied contact installed on the LTB.
If this circuit is open before the compressor is started, the
compressor will not be allowed to operate. Anytime this cir-
cuit is opened for 1 continuous second during compressor
operation, the compressor for that circuit is immediately
turned “Off”. The compressor will not be allowed to restart
for a minimum of 3 minutes should the contacts close.
If four consecutive open conditions occur during the first
three minutes of operation, the compressor for that circuit
will be locked out, a diagnostic communicated to the remote
panel (if installed), and a manual reset will be required to
restart the compressor.
Low Pressure Control
ReliaTel Control
When the LPC is opened for 1 continuous second, the com-
pressor for that circuit is turned off immediately. The com-
pressor will not be allowed to restart for a minimum of 3
minutes.
If four consecutive open conditions occur during an active
call for cooling, the compressor will be locked out, a
diganostic communicated to ICS™, if applicable, and a
manual reset required to restart tyhe compressor. On dual
compressor units only the affected compressor circuit is
locked out.
Electromechanical Control
When the LPC is opened, the compressor for that circuit is
turned off immediately. The compressor will restart when the
LPC closes.
High Pressure Control (Optional — except on
R-410A units)
ReliaTel Control
The high pressure controls are wired in series between the
compressor outputs on the RTRM and the compressor
contactor coils. If the high pressure control switch opens, the
RTRM senses a lack of current while calling for cooling and
locks the compressor out.
If four consecutive open conditions occur during an active call
for cooling, the compressor will be locked out, a diganostic
communicated to ICS™, if applicable, and a manual reset
required to restart tyhe compressor. On dual compressor units
only the affected compressor circuit is locked out.
Electromechanical Control
Whenthe HPCis opened,the compressorfor thatcircuit is
turned off immediately. The compressor will restart when the
HPC closes.
Power Exhaust Control (Optional)
ReliaTel Control
The power exhaust fan is started whenever the position of
the economizer dampers meets or exceed the power ex-
haust setpoint when the indoor fan is on.
With the optional ventilation override accessory, the power
exhaust fan is independent of the indoor fan.
The setpoint panel is located in the return air section and is
factory set at 25%.
Electromechanical Control
The power exhaust fan is started whenever the indoor fan is
on and the adjustable damper limit switch DLS is closed.
Lead/Lag Control (Dual Circuit Only)
ReliaTel Control Only
Lead/Lag is a selectable input located on the RTRM. The
RTRM is configured from the factory with the Lead/Lag
control disabled. To activate the Lead/Lag function, simply
cut the wire connected to J3-8 at the RTRM. When it is
activated, each time the designated lead compressor is shut
off due to the load being satisfied, the lead compressor or
refrigeration circuit switches. When the RTRM is powered
up, i.e. after a power failure, the control will default to the
number one circuit compressor.
Zone Sensor Module (ZSM) (BAYSENS006B)
This electronic sensor features three system switch settings
(Heat, Cool, and Off) and two fan settings (On
and Auto). It is a manual changeover control with single
setpoint. (Cooling Setpoint Only)
Zone Sensor Module (ZSM) (BAYSENS008B)
This electronic sensor features four system switch settings
(Heat, Cool, Auto, and Off) and two fan settings (On and
Auto). It is a manual or auto changeover control with dual
setpoint capability. It can be used with a remote zone tem-
perature sensor BAYSENS017B.
Zone Sensor (BAYSENS010B)
This electronic sensor features four system switch settings
(Heat, Cool, Auto, and Off) and two fan settings (On and
Auto) with four system status LED’s. It is a manual or auto
changeover control with dual setpoint capability. It can be
used with a remote zone temperature sensor
BAYSENS017B.
Wall Mounted Relative Humidity Sensor (BAYSENS036A)
Field installed, wall mounted humidity sensor is used to
control activation of the hot gas reheat dehumidification
option. Humidity set points can be selected for relative
humidity levels between 40% and 60% by adjusting the
DEHUMID setting on the ReliaTel Options Module. See
page 24.

7
General Information
Duct Mounted Relative Humidity Sensor (BAYSENS037A)
Field installed, duct mounted humidity sensor is used to
control activation of the hot gas reheat dehumidification
option. Humidity set points can be selected for relative
humidity levels between 40% and 60% by adjusting the
DEHUMID setting on the ReliaTel Options Module. See page
24.
Programmable Zone Sensor - (BAYSENS019B)
This 7 day programmable sensor features 2, 3 or 4 periods
for Occupied or Unoccupied programming per day. If the
power is interrupted, the program is retained in permanent
memory. If power is off for an extended period of time, only
the clock and day may have to be reset.
The Zone Sensor allows selection of 2, 3 or 4 system modes
(Heat, Cool, Auto, and Off), two fan modes (On and Auto). It
has dual temperature selection with programmable start time
capability.
The occupied cooling set point ranges between 45 and 98
degrees Fahrenheit. The heating set point ranges between
43 and 96 degrees Fahrenheit.
A liquid crystal display (LCD) displays zone temperature,
temperature set points, day of the week, time, and opera-
tional mode symbols.
The Option Menu is used to enable or disable applicable
functions, i.e.; Morning Warm-up, Economizer minimum posi-
tion override during unoccupied status, Fahrenheit or Centi-
grade, Supply air tempering, Remote zone temperature sen-
sor, 12/24 hour time display, Smart fan, and Computed recov-
ery.
During an occupied period, an auxiliary relay rated for 1.25
amps @ 30 volts AC with one set of single pole double throw
contacts is activated.
Status Inputs (4 Wires Optional)
The ZSM can be wired to receive four (4) operating status
signals from the RTRM (HEAT, COOL, SYSTEM “ON”, SER-
VICE).
Four (4) wires from the RTRM should be connected to
the appropriate terminals (7, 8, 9 & 10) on the ZSM.
Remote Zone Sensor (BAYSENS013B)
This electronic sensor features remote zone sensing and
timed override with override cancellation. It is used with a
Trane Integrated ComfortTM building management system.
Remote Zone Sensor (BAYSENS014B)
This electronic sensor features single setpoint capability and
timed override with override cancellation. It is used with a
Trane Integrated ComfortTM building management system.
Remote Zone Sensor (BAYSENS016A)
This bullet type temperature sensor can be used for; outside
air (ambient) sensing, return air temperature sensing, supply
air temperature sensing, remote temperature sensing (un-
covered. Wiring procedures vary according to the particular
application and equipment involved. Refer to the unit’s wiring
diagrams for proper connections.
Remote Zone Sensor (BAYSENS017B)
This electronic sensor can be used with BAYSENS006B,
008B, 010B, 019B Remote Panels. When this sensor is
wired to a BAYSENS019B Remote Panel, wiring must be
18 AWG Shielded Twisted Pair (Belden 8760 or equiva-
lent). Refer to The specific Remote Panel for wiring details.
Electro Mechanical Control
The unit must have a Thermostat to operate.
BAYSTAT036A
Single Stage - 1 Heat/1 Cool
BAYSTAT037A
Multi Stage - 2 Heat/2 Cool - Can be Used for Economizer
Operation
BAYSENS025A
Remotesensorfor BAYSTAT036Aand BAYSTAT037A
High Temperature Sensor (BAYFRST001A)
This sensor connects to the RTRM Emergency Stop Input
on the LTB and provides high limit “shutdown” of the unit.
The sensor is used to detect high temperatures due to fire
in the air conditioning or ventilation ducts. The sensor is
designed to mount directly to the sheet metal duct. Each kit
contains two sensors. The return air duct sensor
(X1310004001) is set to open at 135 F. The supply air duct
sensor (X1310004002) is set to open at 240 F. The control
can be reset after the temperature has been lowered ap-
proximately 25 F below the cutout setpoint.
Evaporator Frost Control
(ReliaTel™ Option)
This input incorporates the Frostat™ control (FOS)
mounted in the indoor coil circuit and can be activated by
closing a field supplied contact installed in parallel with
theFOS.
If this circuit is open before the compressor is started, the
compressor will not be allowed to operate. Anytime this
circuit is opened for 1 continuous second during compres-
sor operation, the compressor for that circuit is immedi-
ately turned “Off”. The compressor will not be allowed to
restart for a minimum of 3 minutes should the FOS close.
(Electro Mechanical Option)
This input incorporates the Frostat™ control (FOS)
mounted in the indoor coil circuit and can be activated by
opening a field supplied contact installed in series with the
FOS.
If this circuit is open before the compressor is started, the
compressor will not be allowed to operate. Anytime this
circuit is opened during compressor operation, the com-
pressor for that circuit is immediately turned “Off”. The
compressor will restart when the FOS closes.

8
Smoke Detector Sensor (Optional)
This sensor is only applicable on units equipped with a RTOM.
Itprovides highlimit“shutdown” ofthe unitandrequires a
manualreset. Thesensor isused todetectsmokedueto firein
theairconditioningorventilation ducts.
Important:The supply and return air smoke
detectors are designed to shut off the unit if smoke
is sensed in the supply air stream or return air
stream.This function is performed by sampling the
airflow entering the unit at the return air opening.
Follow the instructions provided below to assure that
the airflow through the unit is sufficient for adequate
sampling. Failure to follow these instructions will
prevent the smoke detectors from performing it's
design function.
Important: Airflow through the unit is affected by the
amount of dirt and debris accumulated on the indoor
coil and filters.To insure that airflow through the unit
is adequate for proper sampling by the return air
smoke detector, complete adherence to the
maintenance procedures, including recommended
intervals between filter changes, and coil cleaning is
required.
Important: Periodic checks and maintenance
procedures must be performed on the smoke
detector to insure that it will function properly. For
detailed instructions concerning these checks and
procedures, refer to the appropriate section(s) of the
smoke detector Installation and Maintenance
Instructions provided with the literature package for
this unit.
In order for the supply air smoke detector or return air
smoke detector to properly sense smoke in the supply air
stream or return air stream, the air velocity entering the
smoke detector unit must be between 500 and 4000 feet
per minute. Equipment covered in this manual will develop
an airflow velocity that falls within these limits over the en-
tire airflow range specified in the evaporator fan perfor-
mance tables.
There are certain models, however, if operated at low air-
flow, will not develop an airflow velocity that falls within the
required 500 to 4000 feet per minute range. For these mod-
els, the design airflow shall be greater than or equal to
1000 feet per minute MINIMUM.
Phase Monitor (Optional)
ReliaTel Control Only
This sensor monitors voltage between the 3 conductors of
the 3 phase power supply. Two LED lights are provided. The
green light indicates that a balanced 3 phase supply circuit
is properly connected. The red light indicates that unit op-
eration has been prevented. There are two conditions that
will prevent unit operation.The power supply circuit is not
balanced with the proper phase sequence of L1,L2,L3 for
the 3 conductors of a 3 phase circuit. The line to line voltage
is not between 180 volts and 633 volts.
Pre-Installation Checklist

9
Pre-Installation Checklist
Unit Inspection
As soon as the unit arrives at the job site
[ ] Verify that the nameplate data matches the data on the
sales order and bill of lading (including electrical data).
[ ] Verify that the power supply complies with the unit name-
plate specifications.
[ ] Visually inspect the exterior of the unit, including the roof,
for signs of shipping damage.
WARNING
FiberglassWool !
Product contains fiberglass wool. Disturbing the insula-
tion in this product during installation, maintenance or
repair will expose you to airborne particles of glass wool
fibers and ceramic fibers known to the state of Califor-
nia to cause cancer through inhalation. Glass wool fi-
bers may also cause respiratory, skin or eye irritation.
Precautionary Measures
· Avoid breathing fiberglass dust.
· Use a NIOSH approved dust/mist respirator.
· Avoid contact with the skin or eyes.Wear long-
sleeved, loose-fitting clothing, gloves, and eye protec-
tion.
· Wash clothes separately from other clothing: rinse
washer thoroughly.
· Operations such as sawing, blowing, tear-out,
and spraying may generate fiber concentrations
requiring additional respiratory protection. Use
the appropriate NIOSH approved respiration in
these situations.
First Aid Measures
Eye Contact - Flush eyes with water to remove dust. If
symptoms persist, seek medical attention.
Skin Contact - Wash affected areas gently with soap and
warm water after handling.
Ifthe jobsite inspectionofthe unitreveals damageor material
shortages,filea claimwiththecarrierimmediately.Specifythe
type and extent of the damage on the “bill of lading” before
signing.
[ ] Visually inspect the internal components for shipping
damage as soon as possible after delivery and before it
is stored. Do not walk on the sheet metal base pans.
[ ] If concealed damage is discovered, notify the carrier’s ter-
minal of damage immediately by phone and by mail.
Concealed damage must be reported within 15 days.
Request an immediate joint inspection of the damage by
the carrier and the consignee. Do not remove damaged
material from the receiving location. Take photos of the
damage, if possible. The owner must provide reasonable
evidence that the damage did not occur after delivery.
[ ] Notify the appropriate sales representative before install-
ing or repairing a damaged unit.
Storage
Take precautions to prevent condensate from forming inside
the unit’s electrical compartments and motors if:
a. the unit is stored before it is installed; or,
b. the unit is set on the roof curb, and temporary heat is pro-
vided in the building. Isolate all side panel service en-
trances and base pan openings (e.g., conduit holes, S/A
and R/A openings, and flue openings) from the ambient
air until the unit is ready for start-up.
Note: Do not use the unit’s heater for temporary heat
without first completing the start-up procedure
detailed under“Starting the Unit”.
The manufacturer will not assume any responsibility for
equipment damage resulting from condensate accumula-
tion on the unit’s electrical and/or mechanical components.

10
Unit Clearances
Unit Clearances
Figure 1 illustrates the minimum operating and service
clearances for either a single or multiple unit installation.
These clearances are the minimum distances necessary to
assure adequate serviceability, cataloged unit capacity, and
peak operating efficiency.
Providing less than the recommended clearances may re-
sult in condenser coil starvation, “short-circuiting” of exhaust
and economizer airflows, or recirculation of hot condenser
air.
Figure 1
Typical Installation Clearances for Single & Multiple Unit
Applications

11
Unit Dimensions
Figure 2
Unit Dimensional Data
YHC033A,Y(H/S)C036A,YHC043A,Y(H/S)C048A — Low and Medium Heat
YSC060A — Low and Medium Heat
Unit Dimensional Data
YHC033A, Y(H/S)C036A, YHC043A,Y(H/S)C048A — High Heat
YSC060A — High Heat
YHC060A,YHC063A — Low, Medium, and High Heat
YSC036E, YSC048E, YSC060E

12
Unit Dimensions
Figure 2 - Continued
Unit Dimensional Data
Y(H/S)C072A, YSC090A, YSC092A
Unit Dimensional Data
YHC092A, Y(H/S)102A, Y(H/S)C120A

13
Table 1
Typical UnitWeights & Point Loading Data
Net
Unit Weight
Model (lbs) ABCDLengthWidth
YSC036A1*(L,M,X,Y) 453 143 116 90 104 32 19
YSC036A1*(H,Z) 480 151 124 96 109 32 19
YSC036A(3,4,W)*(L,M,X,Y) 453 143 116 90 104 32 19
YSC036A(3,4,W)*(H,Z) 480 151 124 96 109 32 19
YSC036E(1,3,4,W) 532 165 137 95 134 31 19
YSC048A1*(L,M,X,Y) 478 151 122 102 103 33 19
YSC048A1*(H,Z) 505 159 130 108 109 33 19
YSC048A(3,4,W)*(L,M,X,Y) 465 146 121 101 97 33 19
YSC048A(3,4,W)*(H,Z) 492 154 129 107 103 33 19
YSC048E(1,3,4,W) 563 175 145 101 142 31 19
YSC060A1*(L,M,X,Y) 494 160 127 99 108 32 18
YSC060A1*(H,Z) 522 169 134 105 114 32 18
YSC060A(3,4,K,W)*(L,M,X,Y) 494 160 127 99 108 32 18
YSC060A(3,4,K,W)*(H,Z) 522 169 134 105 114 32 18
YSC060E(1,3,4,W) 613 190 158 110 155 31 19
YSC072A(3,4,K,W)*(L,X) 720 245 188 129 158 39 21
YSC072A(3,4,W)*(M,Y) 731 248 192 131 160 39 21
YSC072A(3,4,K,W)*(H,Z) 735 249 193 132 161 39 21
YSC090A(3,4,K,W)*(L,X) 804 269 203 142 190 38 22
YSC090A(3,4,W)*(M,Y) 808 270 204 143 191 38 22
YSC090A(3,4,K,W)*(H,Z) 820 273 208 146 193 38 22
YSC092A(3,4,W)*(L,X) 806 273 217 143 172 40 21
YSC092A(3,4,W)*(M,Y) 810 274 219 144 173 40 21
YSC092A(3,4,W)*(H,Z) 822 277 222 147 175 40 21
YSC102A(3,4,K,W)*(L,X) 883 293 238 161 191 40 21
YSC102A(3,4,W)*(M,Y) 887 294 239 162 192 40 21
YSC102A(3,4,K,W)*(H,Z) 899 297 243 165 194 40 21
YSC120A(3,4,K,W)*(L,X) 933 310 253 171 198 40 21
YSC120A(3,4,W)*(M,Y) 945 313 257 174 200 40 21
YSC120A(3,4,K,W)*(H,Z) 958 317 261 177 202 40 21
YHC036A1*(L,M,X,Y) 470 150 120 95 105 32 19
YHC036A1*(H,Z) 497 158 128 101 110 32 19
YHC033A(3,4,W)*(L,M,X,Y) 537 159 139 126 111 32 19
YHC036A(3,4,W)*(L,M,X,Y) 470 150 120 95 105 32 19
YHC033A(3,4,W)*(H,Z) 537 159 139 126 111 32 19
YHC036A(3,4,W)*(H,Z) 497 158 128 101 110 32 19
YHC048A1*(M,Y) 511 157 126 108 121 32 20
YHC048A1*(H,Z) 539 166 133 114 126 32 20
YHC043A(3,4,W)*(L,M,X,Y) 577 167 144 139 127 32 20
YHC048A(3,4,W)*(L,M,X,Y) 511 157 126 108 121 32 20
YHC043A(3,4,W)*(H,Z) 577 167 144 139 127 32 20
YHC048A(3,4,W)*(H,Z) 539 166 133 114 126 32 20
YHC060A1*(L,M) 562 176 137 116 133 31 20
YHC060A1*(H,Z) 574 179 140 119 136 32 20
YHC060A(3,4,W)*(L,M,X,Y) 550 175 133 110 131 31 19
YHC063A(3,4,W)*(L,M,X,Y) 612 180 151 144 137 31 19
YHC060A(3,4,W)*(H,Z) 561 178 137 113 134 31 19
YHC063A(3,4,W)*(H,Z) 561 178 137 113 134 31 19
YHC072A(3,4,W)*(L,X) 756 245 193 137 181 39 22
YHC072A(3,4,W)*(M,Y) 768 248 197 140 183 39 22
YHC072A(3,4,W)*(H,Z) 772 249 198 141 184 39 22
YHC092A(3,4,W)*(L,X) 907 302 238 161 207 39 22
YHC092A(3,4,W)*(M,Y) 911 303 239 162 208 39 22
YHC092A(3,4,W)*(H,Z) 923 306 243 165 210 39 22
YHC102A(3,4,W)*(L,X) 942 306 247 171 217 39 22
YHC102A(3,4,W)*(M,Y) 946 307 248 172 218 39 22
YHC102A(3,4,W)*(H,Z) 957 310 252 175 220 40 22
YHC120A(3,4,W)*(L,X) 1035 336 269 191 240 39 22
YHC120A(3,4,W)*(M,Y) 1047 339 272 194 242 39 22
YHC120A(3,4,W) *(H,Z) 1060 342 277 197 245 40 22
Center
Corner Wt. (lbs) of Gravity (In.)
Installation

14
Installation
Typical Accessory Weights
Option / Accessory
Descri
p
tion YHC033, 043, 063 YH/YS036-060 YH/YS072-120
Economizer 26 26 36
Motorized Damper 20 20 30
Manual Damper 16 16 26
Barometric Relief 7 7 10
Power Exhaust N/A N/A 80
Oversize Motor 5 5 8
BeltDrive Motor (3 phase only) Standard 31 Standard
Hinged Access 10 10 12
Hail Guard 12 12 20
Through the Base:Electrical 8 8 13
Through the Base : Gas 5 5 5
Unit Disconnect Switch 5 5 5
Unit Circuit Breaker 5 5 5
Conv. Outlet: Unpowered 2 2 2
Conv. Outlet: Powered 38 38 38
TCI, LCI 1 1 1
NOVAR 8 8 8
HPC 1 1 1
Frostat 1 1 1
Crankcase Heater 1 1 1
Smoke Detector, Return 7 7 7
Smoke Detector, Supply 5 5 5
Clogged Filter Switch 1 1 1
Fan Fail Switch 1 1 1
Discharge Air Tube 3 3 3
Roofcurb 70 70 115
LP Conversion Kit 3 3 3
All Zone Sensors 3 3 1
Hard Start Kit 3 3 N/A
ReheatCoil 15 15 25
Stainless Steel HeatExchanger 5 5 10
Weight - Net lbs
WARNING
Heavy Objects!
Do not use cables (chains or slings) except as shown.
Each of the cables (chains or slings) used to lift the unit
must be capable of supporting the entire weight of the
unit. Lifting cables (chains or slings) may not be of the
same length. Adjust as necessary for even unit lift. Other
lifting arrangements may cause equipment or property-
only damage. Failure to properly lift unit may result in
death or serious injury.
WARNING
Improper Unit Lift!
Test lift unit approximately 24 inches to verify proper
center of gravity lift point.To avoid dropping of unit,repo-
sition lifting point if unit is not level. Failure to properly lift
unit could result in death or serious injury or possible
equipment or property-only damage.
Figure 3
Rigging and Center-of-Gravity Data
Foundation
Horizontal Units
If the unit is installed at ground level, elevate it above the
snow line. Provide concrete footings at each support loca-
tion with a “full perimeter” support structure or a slab foun-
dation for support. Refer to Table 1 for the unit’s operating
and point loading weights when constructing a footing foun-
dation.
If anchoring is required, anchor the unit to the slab using
hold down bolts or isolators. Isolators should be installed to
minimize the transmission of vibrations into the building.
For rooftop applications, ensure the roof is strong enough to
support the combined unit and support structural weight.
Refer to Table 1 for the unit operating weights. If anchoring
is required, anchor the unit to the roof with hold-down bolts
or isolators.
Check with a roofing contractor for proper waterproofing
procedures.

15
Installation
Figure 4-1
3 through 5Ton
Horizontal Unit Supply & Return Air Opening
6 1/4 through 10Ton
Horizontal Unit Supply & Return Air Opening
Supply
Return
Ductwork
Figure 4-1 illustrates the supply and return air openings as
viewed from the rear of the unit.
Elbows with turning vanes or splitters are recommended to
minimize air noise due to turbulence and to reduce static
pressure.
When attaching the ductwork to the unit, provide a water
tight flexible connector at the unit to prevent operating
sounds from transmitting through the ductwork.
All outdoor ductwork between the unit and the structure
should be weather proofed after installation is completed.
Figure 4-1
3 through 5Ton
Downflow Unit Supply & Return Air Openings
6 1/4 through 10Ton
Downflow Unit Supply & Return Air Openings
Roof Curb
Downflow
The roof curbs for these units consists of a “full perimeter”
enclosure to support the unit.
Before installing any roof curb, verify;
1. That it is the correct curb for the unit,
2. That it includes the necessary gaskets and hardware,
3. That the purposed installation location provides the re-
quired clearance for proper operation.
4. Insure that the curb is level and square. The top surface of
the curb must be true to assure an adequate curb-to-unit
seal.

16
WARNING
Combustible Materials!
Maintain proper clearance between the unit heat ex-
changer, vent surfaces and combustible materials. Refer
to unit nameplate and installation instructions for proper
clearances. Improper clearances could result in a fire
hazard. Failure to maintain proper clearances could re-
sult in death or serious injury or property damage.
5. Verify that appropriate materials were used in the con-
struction of roof and ductwork. Combustible materials
should not be used in the construction of ductwork or roof
curb that is in close proximity to heater elements or any
hot surface. Any combustible material on the inside of the
unit base should be removed and replaced with appro-
priate material.
Step-by-step curb assembly and installation instructions
ship with each accessory roof curb kit. Follow the instruc-
tions carefully to assure proper fit-up when the unit is set
into place.
Note:To assure proper condensate flow during
operation, the unit (and curb) must be level.
If the unit is elevated, a field constructed catwalk around the
unit is strongly recommended to provide easy access for
unit maintenance and service.
Recommendations for installing the Supply Air and Return
Air ductwork joining the roof curb are included in the curb
instruction booklet. Curb ductwork must be fabricated and
installed by the installing contractor before the unit is set
into place.
Note: For sound consideration, cut only the holes in
the roof deck for the ductwork penetrations. Do not
cut out the entire roof deck within the curb perimeter.
If a Curb Accessory Kit is not used:
a. The ductwork can be attached directly to the factory-
provided flanges around the unit’s supply and return
air openings. Be sure to use flexible duct connections
at the unit.
b. For “built-up” curbs supplied by others, gaskets must
be installed around the curb perimeter flange and the
supply and return air opening flanges.
Rigging
A Rigging illustration and Center-of-Gravity dimensional
data table is shown in Figure 3. Refer to the typical unit op-
erating weights table before proceeding.
1. Remove all drill screws fastening wood protection to
metal baserail. Remove all screws securing wooden pro-
tection to wooden top crate.
2. Remove Wooden Top Crate.
WARNING
Heavy Objects!
Do not use cables (chains or slings) except as shown.
Each of the cables (chains or slings) used to lift the unit
must be capable of supporting the entire weight of the
unit. Lifting cables (chains or slings) may not be of the
same length. Adjust as necessary for even unit lift. Other
lifting arrangements may cause equipment or property-
only damage. Failure to properly lift unit may result in
death or serious injury. See details below.
3. Rig the unit as shown in Figure 3. Attach adequate
strength lifting slings to all four lifting brackets in the unit
base rail. Do not use cables, chains, or slings except as
shown.
4. Install a lifting bar, as shown in Figure 3, to protect the unit
and to facilitate a uniform lift. The minimum distance be-
tween the lifting hook and the top of the unit should be 7
feet.
5. Test-lift the unit to ensure it is properly rigged and bal-
anced, make any necessary rigging adjustments.
6. Lift the unit enough to allow the removal of two Fork Lift
brackets and hardware. Remove the two Fork Lift brack-
ets, two metal runners and three wooden boards as
shown in the following Figure.
7. Downflow units; align the base rail of the unit with the
curb rail while lowering the unit onto the curb. Make sure
that the gasket on the curb is not damaged while posi-
tioning the unit.
General Unit Requirements
The checklist listed below is a summary of the steps re-
quired to successfully install a commercial unit. This check-
list is intended to acquaint the installing personnel with
what is required in the installation process. It does not re-
place the detailed instructions called out in the applicable
sections of this manual.
[ ] Check the unit for shipping damage and material short-
age; file a freight claim and notify appropriate sales rep-
resentative.
[ ] Verfiy correct model, options and voltage from unit name-
plate.
Installation

17
Installation
[ ] Verify that the installation location of the unit will provide
the required clearance for proper operation.
[ ] Assemble and install the roof curb (if applicable). Refer to
the latest edition of the curb installers guide that ships
with each curb kit.
[ ] Fabricate and install ductwork; secure ductwork to curb.
[ ] Install pitch pocket for power supply through building roof.
(If applicable)
[ ] Rigging the unit.
[ ] Set the unit onto the curb; check for levelness.
[ ] Ensure unit-to-curb seal is tight and without buckles or
cracks.
[ ] Install and connect a condensate drain line to the evapo-
rator drain connection.
Factory Installed Economizer
[ ] Ensure the economizer has been pulled out into the oper-
ating position. Refer to the economizer installers guide
for proper position and setup.
[ ] Install all access panels.
Temperature Limit Switch Usage for Gas Heat Units
Units are factory shipped in the downflow discharge
confriguration but can be field converted to a horizontal dis-
charge confriguration. Some, but not all units require a dif-
ferent TC01 limit switch, which is attached to the combustion
blower motor if horizontal discharge confriguration is used.
Note:The following units require a limit switch
change out for horizontal discharge.The additional
limit switch is shipped attached to the blower
housing. Proceed to the Horizontal Discharge
Conversion, Step 5 on page 18 for the following
models "ONLY". Y*C036A**(H,Z) , Y*C048A**(H,Z),
Y*C060A**(H,Z), YHC060A**(M,Y), Y*C072A**(H,Z),
YSC090A**(M,Y), Y*C092A**(M,Y), YHC092A**(H,Z),
Y*C102A**(M,Y), Y*C102A**(H,Z), Y*C120A**(M,Y),
Y*C120A**(H,Z) YSC036E**(L,X), YSC036E**(M,Y),
YSC036E**(H,Z), YSC048E**(L,X), YSC048E**(M,Y),
YSC048E**(H,Z), YSC060E**(L,X), YSC060E**(M,Y),
YSC060E**(H,Z).
If any of the aforementioned units are installed in the
downflow discharge configuration, remove the additional
TC01 limit switch from the combustion blower motor and
discard.
Horizontal Discharge Conversion
3Through 5Ton Units
If a unit is to be converted to Horizontal discharge, the fol-
lowing conversion must be preformed:
1. Remove the return and supply duct covers.
2. Apply white gasket to the supply duct cover as shown.
White gasket is located in the Ship With bag located in
the control box.
TCO1 Tripping Values
Downflow / Horizontal
YHC033A**(L,X) 170F
YHC033A**(M,Y) 220F
YHC033A**(H,Z) 190F / 210F
YSC036E**(L,X) 170F
Y*C036A**(L,X) 170F
YSC036E**(M,Y) 220F
Y*C036A**(M,Y) 220F
YSC036E**(H,Z) 115F/190F
Y*C036A**(H,Z) 190F / 210F
YHC043A**(L,X) 170F
YHC043A**(M,Y) 170F
YHC043A**(H,Z) 180F /220F
YSC048E**(L,X) 170F
Y*C048A**(L,X) 170F
YSC048E**(M,Y) 190F/200F
Y*C048A**(M,Y) 170F
YSC048E**(H,Z) 155F/200F
Y*C048A**(H,Z) 180F /220F
YSC060E**(L, X) 155
YHC060A**(L,X) 155F
YSC060E**(M,Y) 170F
YHC060A**(M,Y) 155F / 170F
YSC060E**(H,Z) 170F
YHC060A**(H,Z) 170F / 200F
YHC063A**(L,X) 155F
YHC063A**(M,Y) 155F / 170F
YHC063A**(H,Z) 170F / 200F
YSC060A**(L,X) 170F
YSC060A**(M,Y) 170F
YSC060A**(H,Z) 170F / 200F
Y*C072A**(L,X) 200F
Y*C072A**(M,Y) 200F
Y*C072A**(H,Z) 180F / 210F
YSC090A**(L,X) 200F
YSC090A**(M,Y) 180F / 220F
YSC090A**(H,Z) 200F
YHC092A**(L,X) 225F
YHC092A**(M,Y) 180F / 220F
YHC092A**(H,Z) 180F /220F
YSC092A**(L,X) 200F
YSC092A**(M,Y) 180F / 220F
YSC092A**(H,Z) 200F
Y*C102A**(L,X) 225F
Y*C102A**(M,Y) 180F / 220F
Y*C102A**(H,Z) 190F / 260F
Y*C120A**(L,X) 200F
Y*C120A**(M,Y) 190F / 260F
Y*C120A**(H,Z) 190F / 260F
Unit Model

18
Installation
3. Position duct covers as shown below. Rotate supply duct
cover 90 degrees to allow it to be slid into supply open-
ing.
Note: If unit is equipped with Return Air Smoke
Detector refer to field conversion for horizontal
discharge before installing return air duct cover.
4. Slide duct covers into duct openings until endward edge
of the duct cover engages with the 2 retaining clips on
the duct flanges. Secure the outward edge of the each
duct cover with 2 screws.
Note:The following units require a limit switch
change out.The additional limit switch is shipped
attached to the blower housing for these
models.Proceed to Step 5 for the following models
"ONLY". YHC033A**(H,Z), YSC036E**(H,Z),
YHC043A**(H,Z), YHC063A**(H,Z), Y*C036A**(H,Z),
YSC048E**(H,Z), Y*C048A**(H,Z), YSC048E**(M,Y),
Y*C060A**(H,Z), YHC060A**(M,Y)
5. After completing installation of the duct covers for hori-
zontal discharge, proceed to TCO-A instructions.
TCO-A Instructions:
If the unit being installed is listed in the following table the
limit control TCO1 must be replaced with the extra limit con-
trol shipped in the heater compartment. Replace TCO1 fol-
lowing the instructions in steps 1through 3 below. If the unit
being installed does not correspond to any in the following
table, skip steps1 through 3 and go on to next step in the in-
stallation process.
Y*C036A**(H,Z), YSC048E**(H,Z), Y*C048A**(H,Z),
Y*C060A**(H,Z), YHC060A**(M,Y)
Unit Model Number
YHC033A**(H,Z), YSC036E**(H,Z),YHC043A**(H,Z),
YHC063A**(M,Y), YSC048E**(M,Y), YHC063A**(H,Z),
WARNING
Hazardous Voltage!
Disconnect all electric power,including remote discon-
nects before servicing. Follow proper lockout/tagout pro-
cedures to ensure the power can not be inadvertently en-
ergized. Failure to disconnect power before servicing
could result in death or serious injury.
1. Remove the heat section access panel.
2. Remove TC01 from shipping location, attached to the
combustion blower.
3. Replace and discard the existing TC01 originally installed
at the factory for downflow operation with the TC01
shipped attached to the combustion blower for horizontal
operation.
4. Replace heat section access panel.
Horizontal Discharge Conversion
6Through 10Ton Units
If a unit is to be converted to Horizontal discharge, the fol-
lowing conversion must be preformed:
1. Remove the return and supply duct covers.
2. Apply white gasket to the supply duct cover as shown.
White gasket is located in the Ship With bag located in
the control box.

19
3. Position duct covers as shown below. The supply duct
cover is installed ( insulation side down )over the
downflow return opening by engaging one side of the
panel under a retaining angle and securing the other
side with 3 screws.
Note: If unit is equipped with Return Air Smoke
Detector refer to field conversion for horizontal
discharge before installing return air duct cover.
4. Slide return duct cover ( insulation side up ) into supply
openings until endward edge of the duct cover engages
with the 2 retaining clips on the duct flanges. Secure the
outward edge of the each duct cover with 2 screws.
Note:The following units require a limit switch
change out.The additional limit switch is shipped
attached to the blower housing for these models.
Proceed to Step 5 for the following models "ONLY".
Y*C072A**(H,Z), YSC090A**(M,Y), Y*C092A**(M,Y),
YHC092A**(H,Z), Y*C102A**(M,Y), Y*C102A**(H,Z),
Y*C120A**(M,Y), Y*C120A**(H,Z).
5. After completing installation of the duct covers for hori-
zontal discharge, proceed to TCO-A instructions.
TCO-A Instructions:
If the unit being installed is listed in the following table the
limit control TCO1 must be replaced with the extra limit con-
trol shipped in the heater compartment. Replace TCO1 fol-
lowing the instructions in steps 1through 3 below. If the unit
being installed does not correspond to any in the following
table, skip steps1 through 3 and go on to next step in the in-
stallation process.
Installation
Y*C092A**(M,Y), YHC092A**(H,Z),
Y*C102A**(M,Y), Y*C102A**(H,Z),
Y*C120A**(M,Y), Y*C120A**(H,Z)
Unit Model Number
Y*C072A**(H,Z), YSC090A**(M,Y),
WARNING
Hazardous Voltage!
Disconnect all electric power,including remote discon-
nects before servicing. Follow proper lockout/tagout pro-
cedures to ensure the power can not be inadvertently en-
ergized. Failure to disconnect power before servicing
could result in death or serious injury.
1. Remove the heat section access panel.
2. Remove TC01 from shipping location, attached to the
combustion blower.
3. Replace and discard the existing TC01 originally installed
at the factory for downflow operation with the TC01
shipped attached to the combustion blower for horizontal
operation.
4. Replace heat section access panel.
Return Air Smoke Detector
The factory installed Return Air Smoke Detector is installed
in the Downflow discharge position. No additional field
setup is required.
If a unit is to be converted to Horizontal discharge, the fol-
lowing conversion must be performed:
1. If the unit has an economizer, it must be pulled out in the
operating position.

20
Installation
2.Remove the3screws fromthe mountingbrackets. Referto
DownflowView forscrew locations.
3. Lift the tube and bracket from the downflow duct opening.
Rotate the tube and bracket assembly 180 degrees en-
suring that the holes on the copper sensing tube face
away from the unit and face the return air ductwork. Refer
to Horizontal View.
Note: Check to insure that the flexible tubing lies flat
on the base pan surface.
4. Slide the top bracket down the copper sensing tube, in-
sert the tab on the left side into the slot on the indoor coil
blockoff and secure the right side of the bracket with one
of the 3 screws removed in step 2. Refer to Horizontal
View.
5.Using theremaining2 screwsremoved instep 2,secure the
bottombracket. Referto HorizontalView.
Main Electrical Power Requirements
[ ] Verify that the power supply complies with the unit name-
plate specifications.
[ ] Inspect all control panel components; tighten any loose
connections.
[ ] Connect properly sized and protected power supply wir-
ing to a field-supplied/installed disconnect switch and to
the main power terminal block (HTB1) in the unit control
panel.
[ ] Install proper grounding wires to an earth ground.