York MILLENNIUM Y22 User manual

CONTENTS
NOMENCLATURE. . . . . . . . . . . . . . . . . . . . . . . . . . . 6
GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . 8
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
GAS HEATING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
GAS FURNACE OPERATING INSTRUCTIONS. . . 68
MILLENNIUM SEQUENCE OF OPERATION . . . . . 70
TROUBLESHOOTING A MILLENNIUM SIMPLICITY
CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
THE MILLENNIUM SIMPLICITY CONTROL. . . . . . 96
SIMPLICITY PROGRAMMING OPTIONS. . . . . . . 106
SETTABLE SYSTEM PARAMETERS. . . . . . . . . . 106
SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
MAINTENANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . 131
See the following pages for a complete Table of Contents.
NOTES, CAUTIONS AND WARNINGS
Installer should pay particular attention to the words: NOTE,
CAUTION, and WARNING. Notes are intended to clarify or
make the installation easier. Cautions are given to prevent
equipment damage. Warnings are given to alert installer
that personal injury and/or equipment damage may result if
installation procedure is not handled properly.
INSTALLATION
MANUAL
CAUTION: READ ALL SAFETY GUIDES BEFORE YOU
BEGIN TO INSTALL YOUR UNIT.
SAVE THIS MANUAL
MILLENNIUM™ ROOFTOP
25, 30 & 40 TON
102777-YIM-E-0206
MODELS: Y22
Y23
Y24

102777-YIM-E-0206
2Unitary Products Group
TABLE OF CONTENTS
NOMENCLATURE. . . . . . . . . . . . . . . . . . . . . . . . . . . 6
GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . 8
NOTES, CAUTIONS AND WARNINGS. . . . . . . . . . . . . . .8
GAS FIRED MODELS . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
WHAT TO DO IF YOU SMELL GAS . . . . . . . . . . . . . . . . . . . . .8
ALL MODELS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
INSPECTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
REFERENCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
APPROVALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
INSTALLATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
LIMITATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
LOCATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
RIGGING AND HANDLING . . . . . . . . . . . . . . . . . . . . . . .12
CLEARANCES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
DUCTWORK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
AIR HOODS FOR FIXED OUTSIDE AIR
(UNITS WITHOUT ECONOMIZER). . . . . . . . . . . . . . . . .13
AIR HOODS FOR ECONOMIZER. . . . . . . . . . . . . . . . . .13
AIR HOODS FOR EXHAUST AIR . . . . . . . . . . . . . . . . . .13
CONDENSATE DRAIN . . . . . . . . . . . . . . . . . . . . . . . . . .13
SERVICE ACCESS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
COMPRESSORS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
FILTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
THERMOSTAT (CONSTANT VOLUME UNITS). . . . . . .14
SPACE SENSOR (VARIABLE AIR VOLUME UNITS). . .14
POWER AND CONTROL WIRING . . . . . . . . . . . . . . . . .15
POWER WIRING DETAIL . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
ERV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
GAS HEATING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
GAS PIPING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
GAS CONNECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
VENT AND COMBUSTION AIR. . . . . . . . . . . . . . . . . . . .17
233 & 466 MBH HEAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
699 MBH HEAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
ELECTRIC HEAT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
HOT WATER HEAT. . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
PIPING CONNECTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
STEAM HEAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
PIPING CONNECTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
STATIC PRESSURE CONTROL PLASTIC TUBING . . .20
EXHAUST STATIC PRESSURE . . . . . . . . . . . . . . . . . . .20
CFM, STATIC PRESSURE, AND POWER - ALTITUDE
AND TEMPERATURE CORRECTIONS . . . . . . . . . . . . .46
START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
COMPRESSOR ROTATION . . . . . . . . . . . . . . . . . . . . . .63
SUPPLY AIR FAN INSTRUCTIONS . . . . . . . . . . . . . . . .63
CHECK BLOWER BEARING SET SCREWS. . . . . . . . . . . . . .63
CHECKING SUPPLY AIR CFM . . . . . . . . . . . . . . . . . . . . . . . .63
FAN ROTATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
BELT TENSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
AIR BALANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
CHECKING AIR QUANTITY . . . . . . . . . . . . . . . . . . . . . . . . . . 63
SUPPLY AIR DRIVE ADJUSTMENT . . . . . . . . . . . . . . . . . . . 65
SYSTEM SETPOINTS. . . . . . . . . . . . . . . . . . . . . . . . . . . 65
CONSTANT VOLUME AND VARIABLE AIR VOLUME:. . . . . 65
GAS FURNACE OPERATING
INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
TO LIGHT THE MAIN BURNERS . . . . . . . . . . . . . . . . . . 68
TO SHUT DOWN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
POST-START CHECKLIST (GAS) . . . . . . . . . . . . . . . . . 68
MANIFOLD GAS PRESSURE ADJUSTMENT . . . . . . . . 68
BURNER INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . 69
ADJUSTMENT OF TEMPERATURE RISE. . . . . . . . . . . 69
CHECKING GAS INPUT . . . . . . . . . . . . . . . . . . . . . . . . . 69
NATURAL GAS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
ELECTRIC HEATING . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
COOLING OPERATING INSTRUCTIONS . . . . . . . . . . . 70
COMPRESSOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
INTERNAL WIRING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
CONDENSER FANS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
MILLENNIUM SEQUENCE OF OPERATION . . . . . 70
OVERVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
RUN SEQUENCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
UNIT CONTROLS SEQUENCE . . . . . . . . . . . . . . . . . . . 71
VARIABLE AIR VOLUME UNIT (VFD & IGV) . . . . . . . . . 73
OVERVIEW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
OCCUPIED / UNOCCUPIED / MORNING WARM-UP . . 73
OCCUPIED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
UNOCCUPIED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
MORNING WARM-UP [MWUP] . . . . . . . . . . . . . . . . . . . . . . . 74
UNIT CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
HEAD PRESSURE CONTROL . . . . . . . . . . . . . . . . . . . . 77
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
SEQUENCE OF OPERATION - FOR HEAD PRESSURE
CONTROL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
INTELLI-START. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
LEAD LAG. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
DEVICES AND RULES . . . . . . . . . . . . . . . . . . . . . . . . . . 77
AIR PROVING SWITCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
FAN DELAYS:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
COMFORT VENTILATION MODE . . . . . . . . . . . . . . . . . 78
ECONOMIZER CONTROL DURING COMFORT
VENTILATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
STAGING CONTROL DURING COMFORT VENTILATION. . 79
HYDRONIC HEAT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
COOLING LOCKOUT ON OAT. . . . . . . . . . . . . . . . . . . . 80
WATER COIL FREEZE STAT (FSI) . . . . . . . . . . . . . . . . 80
CV OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
THERMOSTAT OPERATION FOR COOLING WITH Y1,
Y2, Y3 AND Y4 INPUTS . . . . . . . . . . . . . . . . . . . . . . . . . 80
GROUPING COMPRESSORS INTO STAGES . . . . . . . . . . . 81
ECONOMIZER MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

102777-YIM-E-0206
Unitary Products Group 3
OPERATION FOR HEATING WITH W1, W2, AND W3
INPUTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
SUPPLY FAN OFF DELAY . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
HEAT STAGE DELAYS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
THERMOSTAT OPERATION WITH HYDRONIC HEAT . . . . . 81
SENSOR OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . 81
TYPES OF SPACE SENSORS. . . . . . . . . . . . . . . . . . . . 81
SUPPLY FAN CONTROL WHEN USING A ZONE SENSOR .82
SUPPLY FAN OFF DELAY . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
CONTROL OF COMPRESSORS WHEN USING A ZONE
SENSOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82
HEATING OPERATION WITH THE SENSOR OPTION . . . . . 82
COOLING OPERATION WITH THE SENSOR OPTION . . . . . 82
VAV OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
VAV OPERATION WITH A THERMOSTAT. . . . . . . . . . . . . . . 83
VAV OPERATION WITH A ZONE SENSOR . . . . . . . . . . . . . . 83
STANDALONE VAV OPERATION. . . . . . . . . . . . . . . . . . . . . .83
SUPPLY FAN OFF DELAY . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
OCCUPIED HEATING WITH A THERMOSTAT . . . . . . . . . . .83
UNOCCUPIED HEATING WITH A THERMOSTAT. . . . . . . . .84
OCCUPIED COOLING WITH A THERMOSTAT . . . . . . . . . . . 84
UNOCCUPIED COOLING WITH A THERMOSTAT . . . . . . . . 84
OCCUPIED HEATING WITH A SPACE SENSOR. . . . . . . . . .84
UNOCCUPIED HEATING WITH A SPACE SENSOR . . . . . . .84
OCCUPIED COOLING WITH A SPACE SENSOR . . . . . . . . . 84
UNOCCUPIED COOLING WITH A SPACE SENSOR. . . . . . . 84
UNOCCUPIED HEATING IN STANDALONE OPERATION . . 85
OCCUPIED COOLING IN STANDALONE OPERATION. . . . .85
SUPPLY DUCT PRESSURE CONTROL ALGORITHM . 85
MORNING WARM UP / VAV OCCUPIED HEATING
CONTROL ALGORITHM. . . . . . . . . . . . . . . . . . . . . . . . . 85
STARTING MORNING WARM UP. . . . . . . . . . . . . . . . . . . . . .85
MORNING WARM UP / VAV OCCUPIED HEATING
FUNCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85
UNOCCUPIED VAV HEATING / COOLING CONTROL
ALGORITHM WITH A SPACE SENSOR . . . . . . . . . . . . . . . . .86
OCCUPIED VAV HEATING / COOLING CONTROL
ALGORITHM WITH A SPACE SENSOR . . . . . . . . . . . . . . . . .86
CONTROLLING EXCESSIVE SAT (SUPPLY AIR
TEMPERATURE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
SAT CONTROL CONFIGURATION. . . . . . . . . . . . . . . . . . . . . 87
SAT CONTROL FOR COOLING . . . . . . . . . . . . . . . . . . . . . . . 87
ECONOMIZER LOADING OPERATION DURING AN
EXCESSIVE SAT FOR COOLING: . . . . . . . . . . . . . . . . . . . . . 87
CV ECONOMIZER OPERATION. . . . . . . . . . . . . . . . . . . . . . .87
SAT SETPOINTS USED DURING COOLING WITH
ECONOMIZER OPERATION . . . . . . . . . . . . . . . . . . . . . 87
DEMAND VENTILATION. . . . . . . . . . . . . . . . . . . . . . . . . 90
EXHAUST OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . 91
TWO-POSITION CONTROL (NON MODULATING POWER
EXHAUST) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
PROPORTIONAL CONTROL (FAN WITH MODULATING
EXHAUST AIR DAMPER (EAD) CONTROLLED FROM
BUILDING STATIC PRESSURE). . . . . . . . . . . . . . . . . . . . . . .91
PROPORTIONAL CONTROL WITH VFD FAN . . . . . . . . . . . . 92
TWO-POSITION CONTROL (POWER EXHAUST WITH
BAROMETRIC RELIEF, CONTROLLED FROM BUILDING
STATIC PRESSURE). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92
ERV. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
SCHEDULING OPERATION. . . . . . . . . . . . . . . . . . . . . . 92
COMPRESSOR STATUS MONITORING. . . . . . . . . . . . 92
TROUBLESHOOTING A MILLENNIUM SIMPLICITY
CONTROL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95
STATUS LED CHART. . . . . . . . . . . . . . . . . . . . . . . . . . . 95
FAILURE MODES AND DEFAULT OPERATION. . . . . . 95
ERROR HISTORIES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
SENSOR FAILURES AND DEFAULT OPERATION . . . 95
SAT SENSOR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
RAT SENSOR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
OAT SENSOR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
OUTSIDE AIR RELATIVE HUMIDITY SENSOR . . . . . . . . . . 95
RETURN AIR RELATIVE HUMIDITY SENSOR . . . . . . . . . . . 95
SPACE TEMPERATURE SENSOR . . . . . . . . . . . . . . . . . . . . 96
BUILDING PRESSURE SENSOR . . . . . . . . . . . . . . . . . . . . . 96
DUCT STATIC PRESSURE SENSOR . . . . . . . . . . . . . . . . . . 96
IAQ SENSOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
SYSTEM ERRORS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
HEATING SAT FAILURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
COOLING SAT FAILURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
SUPPLY FAN FAILURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
COMPRESSOR SAFETY CHAIN TRIP . . . . . . . . . . . . . . . . . 96
DIRTY FILTER ALARM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
HIGH DUCT STATIC ALARM. . . . . . . . . . . . . . . . . . . . . . . . . 96
HOT WATER COIL FREEZE ALARM. . . . . . . . . . . . . . . . . . . 96
THE MILLENNIUM SIMPLICITY CONTROL . . . . . .96
INTRODUCTION AND OVERVIEW . . . . . . . . . . . . . . . . 96
DIAGNOSTICS VIA LED. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
ERROR HISTORY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
DIGITAL LINGO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
THE PI ALGORITHM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
ANALOG TO DIGITAL CONVERTER. . . . . . . . . . . . . . . 98
SOFTWARE TERMINOLOGY . . . . . . . . . . . . . . . . . . . . . . . . 98
COMMUNICATIONS BUS . . . . . . . . . . . . . . . . . . . . . . . 99
OPTIONAL MODLINC TRANSLATOR . . . . . . . . . . . . . . 99
OVERVIEW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
COMPONENT DESCRIPTION . . . . . . . . . . . . . . . . . . . . 99
THE SIMPLICITY CONTROLLER . . . . . . . . . . . . . . . . . . . . . 99
WIRING AND TERMINATION, COMMUNICATIONS. . . . . . 100
COMMUNICATION ADDRESS: . . . . . . . . . . . . . . . . . . . . . . 100
ACRONYMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
INPUTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
ANALOG INPUTS (AI):. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
BINARY INPUTS (BI):. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
OUTPUTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
BINARY OUTPUTS (BO) . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
H1-3 - HEAT STAGES 1 TO 3 [OPTIONAL]. . . . . . . . . . . . . 103
SIMPLICITY PROGRAMMING OPTIONS . . . . . . .106
INTERACTING THROUGH THE MILLENNIUM
SIMPLICITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
SET THE CLOCK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
PARAMETER SETTING. . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
INITIAL STARTUP OPTIONS. . . . . . . . . . . . . . . . . . . . 106
METRIC OPERATION (ENGLISH). . . . . . . . . . . . . . . . 106

102777-YIM-E-0206
4Unitary Products Group
SETTABLE SYSTEM PARAMETERS . . . . . . . . . 106
SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
REFRIGERATION SYSTEM . . . . . . . . . . . . . . . . . . . . .114
COMPRESSORS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114
MOTORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114
INDOOR BLOWER MOTORS . . . . . . . . . . . . . . . . . . . . . . . .114
POWER EXHAUST OR RETURN AIR FAN MOTORS . . . . .114
CONDENSER FAN MOTORS . . . . . . . . . . . . . . . . . . . . . . . .114
DRAFT MOTOR (GAS FURNACE) . . . . . . . . . . . . . . . . . . . .114
GAS FURNACE SAFETY FEATURES . . . . . . . . . . . . .131
COMBUSTION AIR PROVING. . . . . . . . . . . . . . . . . . . . . . . .131
ROLLOUT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131
MAINTENANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . 131
NORMAL MAINTENANCE. . . . . . . . . . . . . . . . . . . . . . .131
FILTERS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131
MOTORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131
FAN DRIVES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .132
OUTDOOR COIL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .132
GAS BURNER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .132
TO CLEAN BURNERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .132
COMBUSTION AIR DISCHARGE . . . . . . . . . . . . . . . . . . . . .132
CLEANING FLUE PASSAGES AND HEATING ELEMENTS.132
SECURE OWNERS APPROVAL. . . . . . . . . . . . . . . . . .133
LIST OF FIGURES
Fig. # Pg. #
1 COMPONENT LOCATION . . . . . . . . . . . . . . . . . . . . . . .7
2 TYPICAL RIGGING . . . . . . . . . . . . . . . . . . . . . . . . . . .10
3 CENTER OF GRAVITY . . . . . . . . . . . . . . . . . . . . . . . .11
4 RECOMMENDED DRAIN PIPING . . . . . . . . . . . . . . . .14
5 TYPICAL THERMOSTAT WIRING. . . . . . . . . . . . . . . .14
6 TYPICAL GAS PIPING CONNECTION . . . . . . . . . . . .16
7 VENT AND COMBUSTION AIR HOODS . . . . . . . . . . .17
8 699 MBH HEAT VENT . . . . . . . . . . . . . . . . . . . . . . . . .17
9 FLUE EXTENSION . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
10 CLEARANCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
11 HOT WATER PIPING CROSS-SECTION . . . . . . . . . .19
12 STEAM PIPING CROSS-SECTION . . . . . . . . . . . . . . .19
13 BOTTOM SUPPLY AND RETURN. . . . . . . . . . . . . . . .39
14 END RETURN, BOTTOM SUPPLY . . . . . . . . . . . . . . .40
15 BOTTOM RETURN, FRONT & REAR SUPPLY. . . . . .41
16 END RETURN, FRONT & REAR SUPPLY . . . . . . . . .42
17 FIELD INSTALLED DISCONNECT . . . . . . . . . . . . . . .43
18 PARTIAL ROOF CURB MODEL 1RC0455P . . . . . . . .44
19 FULL ROOF CURB MODEL 1RC0455F . . . . . . . . . . .45
20 ALTITUDE/TEMPERATURE CONVERSION FACTOR 47
21 FAN PERFORMANCE - 25 TON . . . . . . . . . . . . . . . . .50
22 FAN PERFORMANCE - 30 TON . . . . . . . . . . . . . . . . .53
23 FAN PERFORMANCE - 40 TON . . . . . . . . . . . . . . . . .56
24 POWER EXHAUST - ONE FORWARD CURVE FAN -
25 TONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
25 POWER EXHAUST - TWO FORWARD CURVED FANS -
30 & 40 TONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
26 BELT TENSION ADJUSTMENT . . . . . . . . . . . . . . . . . 63
27 TYPICAL GAS VALVE . . . . . . . . . . . . . . . . . . . . . . . . . 69
28 TYPICAL FLAME APPEARANCE . . . . . . . . . . . . . . . . 70
29 COMFORT VENTILATION ECONOMIZER
CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
30 SAT CONTROL BAND . . . . . . . . . . . . . . . . . . . . . . . . . 85
31 SIMPLICITY CONTROLLER . . . . . . . . . . . . . . . . . . . . 97
32 SIMPLICITY CONTROLS PUSH BUTTONS . . . . . . . . 97
33 ANALOG TO DIGITAL CONVERTER . . . . . . . . . . . . . 98
34 VFD CONTROL WIRING . . . . . . . . . . . . . . . . . . . . . . 102
35 SEQUENCE OF SETTING THE SET POINTS . . . . . 109
36 HOT WATER COIL - 25 & 30 TON, 1 ROW,
AT 10 GPM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
37 HOT WATER COIL - 25 & 30 TON, 1 ROW,
AT 20 GPM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
38 HOT WATER COIL - 25 & 30 TON, 1 ROW,
AT 30 GPM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
39 HOT WATER COIL - 25 & 30 TON, 1 ROW,
AT 40 GPM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
40 HOT WATER COIL - 25 & 30 TON, 2 ROW,
AT 60 GPM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
41 HOT WATER COIL - 25 & 30 TON, 2 ROW,
AT 80 GPM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
42 HOT WATER COIL - 40 TON, 1 ROW, AT 10 GPM . 121
43 HOT WATER COIL - 40 TON, 1 ROW, AT 20 GPM . 121
44 HOT WATER COIL - 40 TON, 1 ROW, AT 30 GPM . 122
45 HOT WATER COIL - 40 TON, 1 ROW, AT 40 GPM . 122
46 HOT WATER COIL - 40 TON, 2 ROW, AT 20 GPM . 123
47 HOT WATER COIL - 40 TON, 2 ROW, AT 40 GPM . 123
48 HOT WATER COIL - 40 TON, 2 ROW, AT 60 GPM . 124
49 HOT WATER COIL - 40 TON, 2 ROW, AT 80 GPM . 124
50 STEAM COIL - 25 & 30 TON (1 ROW) . . . . . . . . . . . 125
51 STEAM COIL - 40 TON (1 ROW). . . . . . . . . . . . . . . . 125
52 TYPICAL CONTROL WIRING . . . . . . . . . . . . . . . . . . 126
53 LEGEND. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
54 TYPICAL 25 TON POWER WIRING . . . . . . . . . . . . . 128
55 TYPICAL 30/40 TON POWER WIRING . . . . . . . . . . . 129
56 TYPICAL GAS HEAT WIRING . . . . . . . . . . . . . . . . . . 130
57 TYPICAL FLUE BAFFLE . . . . . . . . . . . . . . . . . . . . . . 133
58 25 TON CHARGING CURVE . . . . . . . . . . . . . . . . . . . 134
59 30 TON CHARGING CURVE . . . . . . . . . . . . . . . . . . . 135
60 40 TON CHARGING CURVE . . . . . . . . . . . . . . . . . . . 136
61 PRESSURE DROP DRY EVAPORATOR COIL VS
SUPPLY AIR CFM - 25 TON . . . . . . . . . . . . . . . . . . . 137
62 PRESSURE DROP DRY EVAPORATOR COIL VS
SUPPLY AIR CFM - 30 & 40 TON . . . . . . . . . . . . . . 138

102777-YIM-E-0206
Unitary Products Group 5
LIST OF TABLES
Tbl. # Pg. #
1 COOLING & ELECTRICAL APPLICATION . . . . . . . . . . 9
2 COOLING & ELEC. APP. LIMITATIONS. . . . . . . . . . . . 9
3 GAS APPLICATION DATA . . . . . . . . . . . . . . . . . . . . . 10
4 UNIT WEIGHTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5 SUPPLY FAN MOTOR VFD WEIGHTS . . . . . . . . . . . 11
6 EXHAUST FAN MOTOR VFD WEIGHTS . . . . . . . . . . 11
7 UNIT CORNERWEIGHT . . . . . . . . . . . . . . . . . . . . . . . 12
8 UNIT CENTER OF GRAVITY . . . . . . . . . . . . . . . . . . . 12
9 CONTROL WIRE SIZES . . . . . . . . . . . . . . . . . . . . . . . 14
10 PIPE SIZES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
11 GENERAL PHYSICAL DATA . . . . . . . . . . . . . . . . . . . 21
12 REFRIGERANT CHARGE. . . . . . . . . . . . . . . . . . . . . . 22
13 ELECTRICAL DATA BASIC UNIT - 25 TON . . . . . . . . 22
14 ELECTRICAL DATA BASIC UNIT - 30 TON . . . . . . . . 23
15 ELECTRICAL DATA BASIC UNIT - 40 TON . . . . . . . . 23
16 ELECTRICAL DATA BASIC UNIT WITH ELECTRIC
HEAT - 25 TON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
17 ELECTRICAL DATA BASIC UNIT WITH ELECTRIC
HEAT - 30 TON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
18 ELECTRICAL DATA BASIC UNIT WITH ELECTRIC
HEAT - 40 TON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
19 ELECTRICAL DATA BASIC UNIT WITH POWER
EXHAUST - 25 TON . . . . . . . . . . . . . . . . . . . . . . . . . . 27
20 ELECTRICAL DATA BASIC UNIT WITH POWER
EXHAUST - 30 TON . . . . . . . . . . . . . . . . . . . . . . . . . . 28
21 ELECTRICAL DATA BASIC UNIT WITH POWER
EXHAUST - 40 TON . . . . . . . . . . . . . . . . . . . . . . . . . . 29
22 ELECTRICALDATABASIC UNIT W/POWEREXHAUST
& ELECTRIC HEAT - 25 TON . . . . . . . . . . . . . . . . . . . 30
23 ELECTRICALDATABASIC UNIT W/POWEREXHAUST
& ELECTRIC HEAT - 30 TON . . . . . . . . . . . . . . . . . . . 33
24 ELECTRICALDATABASIC UNIT W/POWEREXHAUST
& ELECTRIC HEAT - 40 TON . . . . . . . . . . . . . . . . . . . 36
25 ALTITUDE CORRECTION FACTORS . . . . . . . . . . . . 46
26 FAN PERFORMANCE - 25 TON . . . . . . . . . . . . . . . . 48
27 FAN PERFORMANCE - 30 TON . . . . . . . . . . . . . . . . 51
28 FAN PERFORMANCE - 40 TON . . . . . . . . . . . . . . . . 54
29 COMPONENT STATIC RESISTANCE . . . . . . . . . . . . 57
30 SUPPLY FAN MOTOR AND DRIVE DATA . . . . . . . . . 58
31 EXHAUST FAN DRIVE DATA . . . . . . . . . . . . . . . . . . . 58
32 POWER EXHAUST - ONE FORWARD CURVED FAN
25 TON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
33 POWER EXHAUST - TWO FORWARD CURVED
FANS - 30 & 40 TON . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Tbl. # Pg. #
34 BELT ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . 64
35 BLOWER SPEED RATE OF CHANGE. . . . . . . . . . . . 65
36 25 TON DRIVE ADJUSTMENT. . . . . . . . . . . . . . . . . . 66
37 30 TON DRIVE ADJUSTMENT. . . . . . . . . . . . . . . . . . 66
38 40 TON DRIVE ADJUSTMENT. . . . . . . . . . . . . . . . . . 67
39 DRIVE ADJUSTMENT FOR POWER EXHAUST -
25 TON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
40 DRIVE ADJUSTMENT FOR POWER EXHAUST -
30 & 40 TON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
41 GAS RATE - CUBIC FEET PER HOUR . . . . . . . . . . . 69
42 COOLING STAGE. . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
43 COMPRESSOR MINIMUM OFF TIMES . . . . . . . . . . . 81
44 WEEKLY SCHEDULE . . . . . . . . . . . . . . . . . . . . . . . . . 86
45 HOLIDAY SCHEDULE . . . . . . . . . . . . . . . . . . . . . . . . 86
46 ALARM DEFAULT CODES. . . . . . . . . . . . . . . . . . . . . 93
47 STATUS LED CHART. . . . . . . . . . . . . . . . . . . . . . . . . 95
48 ACRONYMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
49 INPUT SIGNAL TO Y1 ACTUATOR POSITION . . . . 102
50 SIMPLICITY CONTROL INPUTS . . . . . . . . . . . . . . . 103
51 SIMPLICITY CONTROL OUTPUTS . . . . . . . . . . . . . 105
52 SETTABLE SYSTEM PARAMETERS. . . . . . . . . . . . 112
53 SYSTEM MOISTURE INDICATOR. . . . . . . . . . . . . . 114
54 STEAM COIL (1 ROW, 25 & 30 TON). . . . . . . . . . . . 115
55 STEAM COIL (1 ROW, 40 TON). . . . . . . . . . . . . . . . 115
56 STATIC RESISTANCE STEAM COIL
(25 & 30 TON) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
57 STATIC RESISTANCE STEAM COIL (40 TON) . . . . 115
58 HOT WATER COIL (1 ROW 25 & 30 TON) . . . . . . . 115
59 HOT WATER COIL (1 ROW, 40 TON). . . . . . . . . . . 116
60 WATER PRESSURE DROP (1 ROW,
25 & 30 TON) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
61 WATER PRESSURE DROP (1 ROW, 40 TONS) . . . 116
62 HOT WATER COIL (2 ROW, 25 & 30 TON) . . . . . . . 116
63 WATER PRESSURE DROP (2 ROW,
25 & 30 TON) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
64 WATER PRESSURE DROP (2 ROW, 40 TON) . . . . 117
65 STATIC RESISTANCE HOT WATER COIL
(25 & 30 TON) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
66 STATIC RESISTANCE HOT WATER COIL
(40 TON) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
67 INDOOR BLOWER BEARING LUBRICATION
SCHEDULE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

102777-YIM-E-0206
6Unitary Products Group
NOMENCLATURE
127(6 
$%277205(7851 %%277206833/< &(1'5(7851 '5($56833/< ()52176833/< )
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102777-YIM-E-0206
Unitary Products Group 7
FIGURE 1 - COMPONENT LOCATION
FILTER ACCESS
EVAPORATOR COIL
AND DRAINPAN ACCESS
POWER & CONTROL WIRING
COMPRESSOR ACCESS
HEAT SECTION
POWER EXHAUST ACCESS
FILTER ACCESS
EVAPORATOR COIL
AND DRAINPAN ACCESS
HEAT SECTION
SUPPLY BLOWER & MOTOR
FILTER DRIERS
RIGHT
SIDE
LEFT SIDE
FRONT
REAR
REAR

102777-YIM-E-0206
8Unitary Products Group
GENERAL
YORK Model Y22/Y23/Y24 units are single package cooling
only or cooling with gas, electric, hot water or steam heating
designed for outdoor installation on a rooftop and for non-res-
idential use.
The units are completely assembled on rigid, permanently
attached base rails. All piping, refrigerant charge, and electri-
cal wiring is factory installed and tested. The units require
electric power, gas, steam, or hot water connections and duct
connections. Gas fired units also require installation of a flue
gas outlet hood.
SAFETY CONSIDERATIONS
NOTES, CAUTIONS AND WARNINGS
Installer should pay particular attention to the words: NOTE,
CAUTION, and WARNING. Notes are intended to clarify or
make the installation easier. Cautions are given to prevent
equipment damage. Warnings are given to alert installer that
personal injury and/or equipment damage may result if instal-
lation procedure is not handled properly.
GAS FIRED MODELS
DO NOT store or use gasoline or other flammable vapors and
liquids in the vicinity of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS
Do not try to light any appliance. Do not touch any electrical
switch. Do not use any phone in your building. Immediately
call your gas supplier from a neighbor’s phone. Follow the
gas supplier’s instructions. If you cannot reach your gas sup-
plier, call the fire department.
ALL MODELS
Installation and servicing of air conditioning equipment can
be hazardous due to system pressure and electrical compo-
nents. Only trained and qualified service personnel should
install, repair or service air conditioning equipment.
Untrained personnel can perform basic maintenance func-
tions of cleaning coils and filters and replacing filters. All other
operations should be performed by trained service personnel.
When working on air conditioning equipment, observe pre-
cautions in the literature, tags and labels attached to the unit
and other safety precautions that may apply.
Follow all safety codes, including ANSI Z223.1-Latest Edi-
tion: wear safety glasses and work gloves; use quenching
cloth for unbrazing operations; have fire extinguisher avail-
able for all brazing operations.
INSPECTION
As soon as a unit is received, it should be inspected for possi-
ble damage during transit. If damage is evident, the extent of
damage should be noted on the carrier’s freight bill. A sepa-
rate request for inspection by the carrier’s agent should be
made in writing.
The furnace and its individual shut-off valve must
be disconnected from the gas supply piping sys-
tem during any pressure testing of that system at
test pressures in excess of 0.5 psig. Pressures
greater than 0.5 will cause gas valve damage
resulting in a hazardous condition. If gas valve is
subjected to a pressure greater than 0.5 psig, it
must be replaced. The furnace must be isolated
from the gas supply piping system by closing its
individual manual shut-off valve during any pres-
sure testing of that system at test pressures equal
to or less than 0.5 psig.
This Furnace is not to be used for temporary heat-
ing of buildings or structures under construction.
Before performing service or maintenance opera-
tions on unit, turn off main power switch to unit.
Electrical shock could cause personal injury.
Improper installation, adjustment, alteration, ser-
vice or maintenance can cause injury or property
damage. Refer to this manual. For assistance or
additional information consult a qualified installer,
service agency or the gas supplier.

102777-YIM-E-0206
Unitary Products Group 9
REFERENCE
Additional information is available in the following reference
forms:
• 036-21091-004 - Technical Guide
• TBD - Unit Replacement Parts List (25, 30 & 40 Tons)
APPROVALS
Designed certified by CGA, ETL, CETL as follows:
1. For use as a forced air furnace with cooling unit (gas
heat models).
2. For outdoor installation only.
3. For installation on combustible material and may be
installed directly on combustible flooring or Class A,
Class B or Class C roof covering materials.
4. For use with natural gas (convertible to LP with kit).
Not suitable for use with conventional venting systems.
INSTALLATION
LIMITATIONS
The installation of this unit must conform to local building
codes, or in the absence of local codes, with ANSI Z223.1
Natural Fuel Gas Code and /or CAN/CGA B149 installation
codes.
In U.S.A.:
1. National Electrical Code ANSI/NFPA No. 70-Latest Edi-
tion.
2. National Fuel Gas Code Z223.1-Latest Edition.
3. Gas-Fired Central Furnace Standard ANSI Z21.47-Lat-
est Edition.
4. Local gas utility requirements.
Refer to Table 1 for Cooling and Electrical Application Data
and to Table 2 for Gas Heat Application Data.
After installation, gas fired units must be adjusted to obtain a
temperature rise within the range specified on the unit rating
plate.
If components are to be added to a unit to meet local codes,
they are to be installed at the contractor's and/or the cus-
tomer's expense.
Size of unit for proposed installation should be based on heat
loss / heat gain calculation made according to the methods of
the Air Conditioning Contractors of America (ACCA).
LOCATION
Use the following guidelines to select a suitable location for
these units:
1. Unit is designed for outdoor installation only.
2. Condenser coils must have an unlimited supply of air.
Where a choice of location is possible, position the unit
on either north or east side of building.
3. Suitable for roof mount on curb.
4. Roof structures must be able to support the weight of the
unit and its accessories. Unit must be installed on a solid
level roof curb or appropriate angle iron frame.
5. Maintain level tolerance to 3/4 inches across width and 2
inches along length.
TABLE 1: COOLING & ELECTRICAL APPLICATION
UNIT POWER
SUPPLY
VOLTAGE VARIATIONS
MIN. VOLTS MAX VOLTS
575-3-60 540 630
208/230-3-60 187 252
460-3-60 432 504
TABLE 2: COOLING & ELEC. APP. LIMITATIONS
LIMITATIONS MODEL
Y22 Y23 Y24
Supply Air CFM
(min./max) 6,000- 12,5000 6,000- 15,000 8,000- 20,000
Entering Wet Bulb
Temp (F°) (min./max) 57/75 57/75 57/75
Ambient Temp 40/120 40/120 40/120
Min. Air Temperature on Gas Fired Heat Exchangers (°F)
Aluminized 25 25 25
Stainless 000

102777-YIM-E-0206
10 Unitary Products Group
TABLE 3: GAS APPLICATION DATA
INPUT CAPACITY (MBH)
AVAILABLE
ON
MODELS
GAS
RATE1
(FT.3/HR.)
TEMP. RISE °F
AT FULL INPUT23
0 TO 2,000 FEET ABOVE
SEA LEVEL 3,000 FEET ABOVE
SEA LEVEL44,000 FEET ABOVE
SEA LEVEL4
MAX. MIN. MAX. MIN. MAX. MIN. MIN. MAX.
233 233 205 205 196 196 Y22, Y23,
Y24 217 5 35
466 233 410 205 392 196 Y22, Y23,
Y24 434 15 45
6995233 615 205 587 196 Y24 650 20 50
1. Based on maximum input and 1075 Btu/Ft.3
2. The air flow must be adjusted to obtain a temperature rise within the range shown.
3. On VAV units, individual room damper boxes must go full open in heating mode to ensure airflow falls within temperature rise
range.
4. For operation at elevations above 2,000 feet and, in the absence of specific recommendations from local authority having jurisdic-
tion, equipment ratings shall be reduced at the rate of 4% for each 1,000 feet above sea level.
5. Minimum heating CFM for 699 MBH input heat is 11,700 CFM.
If a unit is to be installed on a roof curb other than
a YORK roof curb, gasketing must be applied to all
surfaces that come in contact with the unit under-
side.
If a unit is to be installed on an angle iron frame it
is recommended that it be sized to allow the bot-
tom rail to overhang to facilitate installation of con-
densate drains (see Fig. 4).
FIGURE 2 - TYPICAL RIGGING
CABLES
SPREADER BARS
(3 PLACES)
20"
A
B
C
UNIT UNIT WEIGHT
(LB)
LIFTING LUG DIMENSIONS
ABC
25TON
30TON
40TON
SEE NOTE 5
SEE NOTE 5
SEE NOTE 5
8' 4"
8' 4"
8' 4" 6' 9"
6' 9"
6' 9"
2' 3"
2' 3"
2' 3"
RIGGING:
1) RIGWITH 6 CABLES,THREE SPREADER BARS - 95" ACROSS WIDTH AND
SPREADER BARS OF LENGTH EQUALTO "A + B".
2) CENTER OF GRAVITY INCLUDES ECONOMIZER, POWER EXHAUST AND
INLET GUIDE VANES.
3) CAUTION: ALL PANELS MUST BE SECURED IN PLACEWHENTHE UNIT
IS LIFTED.
4) CAUTION: THE CONDENSER COIL SHOULD BE PROTECTED FROM DAMAGE BY
THE RIGGING CABLES WITH PLYWOOD OR OTHER SUITABLE MATERIALS.
5) REFERTO INSTALLATION INSTRUCTIONS.
NOTICETO RIGGERS

102777-YIM-E-0206
Unitary Products Group 11
NOTE: If the Millennium is VAV with ERV, add the
weight of an exhaust VFD - it will be in the unit.
.
TABLE 4: UNIT WEIGHTS
COMPONENT 25 TON 30 TON 40 TON
Basic Unit 4350 4550 4950
Gas Heat
233 MBH 180 180 180
466 MBH 320 320 320
700 MBH - - 450
Electric Heat
40KW 404040
80KW 105 105 105
108KW 110 110 110
Hot Water Heat
1 Row Coil 70 70 70
2 Row Coil 85 85 85
Steam Heat
1 Row Coil 85 85 85
Blower
Forward Curve Fan (Std Fan) 0 0 0
FC IGV 155 155 175
Air Foil Fan 135 135 155
AF IGV 155 155 180
Motor - Supply Fan
7.5hp 110 - -
10hp 145 145 145
15hp 200 200 200
20hp 240 240 240
25hp - 300 300
Supply Fan Motor VFD See Table 5
Refrigeration
Hi Cap. Evap. Coil - 50 15
T-Coat Evap. 32 30 40
T-Coat cond. 32 30 40
Hot Gas Bypass 10 10 10
Low Ambient Head Pressure Control
208-230/380/460 5 5 5
575 252525
Filters
6" Rigid 70 70 70
Exhaust1
1. If ERV and Supply Fan VAV are selected, add the
weight of an Exhaust VFD, Table 5.
Exhaust Type
Barometric 45 65 65
Modulated 140 275 275
Exhaust Motor
5hp 808080
7.5hp 110 110 110
10hp 145 145 145
15hp 200 200 200
Exhaust Motor VFD See Table 6
Economizer
Std. Econ. 235 235 235
Econ. w/ERV 50 50 50
Control
Disconnect 15 15 15
110V outlet 55 55 55
Optilogic 202020
Roof Curb
Partial Curb 415 415 415
Full Curb 615 615 615
TABLE 5: SUPPLY FAN MOTOR VFD WEIGHTS
Supply Fan Motor VFD 230V 460V 575V
W/O Bypass
7.5hp 60 25 30
10hp 60 25 30
15hp 75 50 60
20hp 75 50 60
25hp 115 50 60
W/Bypass
7.5hp 155 90 120
10hp 155 90 120
15hp 185 140 155
20hp 185 140 155
25hp 255 140 155
TABLE 6: EXHAUST FAN MOTOR VFD WEIGHTS
Exhaust Fan Motor 230V 460V 575V
W/O Bypass
5hp 15 10 20
7.5hp 50 15 20
10hp 50 15 20
15hp 65 40 50
25hp 255 140 155
FIGURE 3 - CENTER OF GRAVITY1
1. Refer to Tables 7 and 8 for A, B, C, D and X and Y data
respectively.
All panels must be secured in place when the unit is
lifted.
The condenser coils should be protected from dam-
age by the rigging cables with plywood or other suit-
able material.
An adhesive backed cover is provided over the out-
side of the combustion air inlet opening on gas fired
units to prevent moisture from entering the unit
which could cause damage to electrical compo-
nents. Allow this closure label to remain in place
until the combustion air hood is to be installed (Refer
to Figures 7, 8, & 9).
RIGHT SIDE
CENTEROF
GRAVITY
CONDENSER

COILEND
LEFT SIDE
X
Y
83"
240"
A
B
C
D


BACK

102777-YIM-E-0206
12 Unitary Products Group
RIGGING AND HANDLING
This unit is not designed to be handled with a fork-truck.
Exercise care when moving the unit. Do not remove any
packaging until the unit is near the place of installation. Rig
the unit by attaching chain or cable slings to the holes pro-
vided in lifting lugs. Spreaders MUST be used across the top
of the unit. Refer to Figure 2.
• Rig with six cables and spread with four 95-inch spread-
ers across width and two spreaders of length equal to A
+ B.
• Refer to Tables 4 and 7 for unit weight.
• Center of gravity includes economizer, exhaust or return
air fan and inlet guide vanes (Refer to Table 8).
NOTES: Basic Unit = cooling only, 10hp FC fan.
+ Econ = +235lb
+ Heat = single stage gas, 180 lb
+ Power Exhaust = modulating 7.5hp CLEARANCES
All units require certain clearances for proper operation and
service. Installer must make provisions for adequate combus-
tion and ventilation air in accordance with section 5.3, Air for
Combustion and Ventilation of the National Fuel Gas Code
ANSI Z223.1 or Sections 7.2, 7.3 or 7.4 of CAN/CGA B149
installation codes-Latest Edition and/or applicable provisions
of the local building codes. Refer to Figure 10 for clearances
required for combustible construction, servicing, and proper
unit operation.
TABLE 7: UNIT CORNERWEIGHT
UNIT
DESCRIPTION
25 TON 30 TON 40 TON
ABCDA B C D A B C D
Basic Unit 1033 1033 1215 1215 1079 1053 1269 1294 1131 1131 1417 1417
Basic Unit With
Economizer 1112 1112 1253 1253 1185 1157 1280 1308 1205 1205 1460 1460
Basic Unit With
Economizer and
Gas or Electric Heat 1162 1162 1293 1293 1209 1155 1346 1400 1255 1224 1500 1531
Basic Unit With
Economizer and
Gasor Electric Heat
and Power Exhaust
1284 1284 1296 1296 1359 1298 1389 1449 1416 1384 1532 1563
TABLE 8: UNIT CENTER OF GRAVITY
MODEL 25 TON 30 TON 40 TON
XYXYXY
Basic Unit 99” 46” 98” 45” 93” 46"
Basic Unit With
Econ. 110” 46” 108” 45” 97” 46"
Basic Unit With
Econ. & Gas or
Elect. Heat,
Steam or Hot
Water Heat
104” 45” 102” 44” 96” 45"
Basic Unit With
Econ. & Gas or
Elect. Heat, &
Power Exhaust
118” 45” 112” 44” 108” 45"
(COOLING OPERATION) Do not permit overhang-
ing structures or shrubs to obstruct condenser air
discharge outlet, combustion air inlet or vent out-
lets.

102777-YIM-E-0206
Unitary Products Group 13
DUCTWORK
Ductwork should be designed and sized according to the
methods in Manual Q of the Air Conditioning Contractors of
America (ACCA).
A closed return duct system should be used. This will not pre-
clude use of economizers or outdoor fresh air intake. The
supply and return air duct connections at the unit should be
made with flexible joints to minimize noise.
When the unit is equipped with power exhaust fans or return
air fan the return duct should have a 90 elbow before opening
to the building space to abate noise.
The supply and return air duct systems should be designed
for the CFM and static pressure requirements of the job. They
should NOT be sized to match the dimensions of the duct
connections on the unit.
If the unit is equipped with hot water or steam heat then the
supply air direction will be down only.
AIR HOODS FOR FIXED OUTSIDE AIR
(UNITS WITHOUT ECONOMIZER)
These hoods are factory installed. The dampers may be
adjusted by loosening the thumb screw, turning the lever to
the desired position, and retightening the thumb screw.
AIR HOODS FOR ECONOMIZER
There are (3) economizer outside air intake hoods provided
with the unit. The hood on the end of the unit is factory
mounted. The (2) front and rear hoods are made operational
per the following instructions.
Remove the screws holding the economizer hood shipping
covers in place. Discard covers.
Rotate the hoods out (each hood is hinged in the lower cor-
ner). Secure the hoods with screws along the top and sides.
Apply a bead of RTV sealer along the edge of both hoods
and each pivot joint to prevent water leakage.
Seal any unused screw holes with RTV or by replacing the
screw.
AIR HOODS FOR EXHAUST AIR
When furnished, these hoods and dampers are factory
installed.
CONDENSATE DRAIN
There is one condensate drain connection. Trap the connec-
tion per Figure 4. The trap and drain lines should be pro-
tected from freezing.
Plumbing must conform to local codes. Use a sealing com-
pound on male pipe threads. Install condensate drain lines
from the 1-1/2 inch NPT female connections on the unit to an
open drain.
(GAS HEATING OPERATION)
Excessive exposure to contaminated combustion
air will result in safety and performance related
problems. To maintain combustion air quality, the
recommended source of combustion air is the out-
door air supply.
The outdoor air supplied for combustion should be
free from contaminants due to chemical exposure
that may be present from the following sources:
• Commercial buildings
• Indoor pools
• Laundry rooms
• Hobby or craft rooms
• Chemical storage areas
The following substances should be avoided to
maintain outdoor combustion air quality:
• Permanent wave solutions
• Chlorinated waxes and cleaners
• Chlorine based swimming pool cleaners
• Water softening chemicals
• De-icing salts or chemicals
• Carbon tetrachloride
• Halogen type refrigerants
• Cleaning solvents (such as perchloroethylene)
• Printing inks, paint removers, varnishes, etc.
• Hydrochloric acid
• Cements and glues
• Antistatic fabric softeners for clothes dryers
• Masonry acid washing materials

102777-YIM-E-0206
14 Unitary Products Group
SERVICE ACCESS
Access to all serviceable components is provided by the fol-
lowing hinged doors:
• Furnace compartment
• Supply Air Fan compartment Evaporator Coil compart-
ment (three doors)
• Filter compartment economizer compartment (two doors)
• Power Exhaust compartment (two doors)
• Main control panels (one door)
Refer to Figure 1 for location of these access panels.
COMPRESSORS
Units are shipped with compressor mountings factory-
adjusted and ready for operation.
FILTERS
Throwaway or rigid filters are supplied with each unit. Filters
must always be installed ahead of evaporator coil and must
be kept clean or replaced with same size and type. Dirty fil-
ters will reduce the capacity of the unit and will result in
frosted coils or safety shutdown. Required filter sizes are
shown in Table 11. The unit should not be operated without
filters properly installed.
THERMOSTAT (CONSTANT VOLUME UNITS)
The thermostat, if used, should be located on an inside wall
approximately 56 inches above the floor where it will not be
subject to drafts, sun exposure or heat from electrical fixtures
or appliances. Follow manufacturer's instructions enclosed
with sensor for general installation procedure (See Figure 5).
Refer to Table 9 for control wire sizing and maximum length.
SPACE SENSOR (VARIABLE AIR VOLUME UNITS)
The space sensor, if used, should be located on an inside
wall approximately 56 inch above the floor where it will not be
subject to drafts, sun exposure or heat from electrical fixtures
or appliances. Follow manufacturer's instructions enclosed
with sensor for general installation procedure.
FIGURE 4 - RECOMMENDED DRAIN PIPING
Make sure that all screws and panel latches are
replaced and properly positioned on the unit to
maintain an air-tight seal.
DO NOT loosen compressor mounting bolts.
H - 1 / 2 " P L U S T O T A L S T A T I C P R E S S U R E - M I N I M U M
Y - M I N I M U M 2 "
Y
F I E L D S U P P L I E D
D R A I N C O N N E C T I O N
F A C T O R Y I N S T A L L E D
U N I T B A S
E
H
R O O F
C U R B
O R
P E R I M E T E R
S U P P O R T
S T R U C T U R E
FIGURE 5 - TYPICAL THERMOSTAT WIRING
TABLE 9: CONTROL WIRE SIZES
WIRE SIZE MAXIMUM LENGTH
20 AWG 100 Feet
18 AWG 150 Feet
R C G Y 1 Y 2 Y 3 Y 4 W 1 W 2 A 1 C T T
R
G
Y 1
Y 2
Y 3
Y 4
W 1
W 2
A 1
C
R E M O T E
S E N S O R
2 T H O 4 7 0 2 2 2 4
T 7 3 0 0 T H E R M O S T A T S U B B A S E
L 1 L 2 L 3
ABC
T B 1
E Q U I P . G N D .
P O W E R S U P P L Y
P O W E R W I R I N G

102777-YIM-E-0206
Unitary Products Group 15
POWER AND CONTROL WIRING
Field wiring to the unit must conform to provisions of National
Electrical Code (NEC) ANSI / NFPA 70-Latest Edition and / or
local ordinances. The unit must be electrically grounded in
accordance with the NEC and / or local codes. Voltage toler-
ances which must be maintained at the compressor terminals
during starting and running conditions are indicated on the
unit Rating Plate and Table 1.
The internal wiring harnesses furnished with this unit are an
integral part of the design certified unit. Field alteration to
comply with electrical codes should not be required. If any of
the wire supplied with the unit must be replaced, replacement
wire must be of the type shown on the wiring diagram and the
same minimum gauge as the replaced wire.
Power supply to the unit must be NEC Class 1 and must
comply with all applicable codes. A disconnect switch must
be provided (factory option available). The switch must be
separate from all other circuits. Wire entry at knockout open-
ings requires conduit fittings to comply with NEC and/or Local
Codes. Refer to Figures 13, 14, 15, and 16 for installation
location of openings.
If installing a field mounted disconnect on the unit, refer to
Figure 17 for the recommended mounting location. Unit-
strutTM or equivalent rails should be mounted as shown to
provide structure for mounting. The location of the rails
should be adjusted to fit the disconnect within the dimensions
shown. Conduit run from the disconnect to the power entry
location in the baserail should be routed so that it does not
interfere with the doors of the unit access panels.
NOTE: Since not all local codes allow the mounting of a dis-
connect on the unit, please confirm compliance with
local code before mounting a disconnect on the unit.
Electrical wiring must be sized properly to carry the load.
Each unit must be wired with a separate branch circuit fed
directly from the meter panel and properly fused.
Refer to Figure 5 for typical field wiring and to the appropriate
unit wiring diagram mounted inside control doors for control
circuit and power wiring information.
POWER WIRING DETAIL
Units are factory wired for the voltage shown on the unit
nameplate. The main power block requires copper wires.
Refer to Electrical Data Tables 13 through 24 to size power
wiring, fuses and disconnect switch. All field supplied wiring,
fuses and disconnects must comply with applicable NEC
codes.
Power wiring is brought into the unit through the side of the
baserail or the bottom of the unit/control box inside the curb.
The baserail has a 2-1/2” diameter hole for field wiring and a
3-5/8” hole is provided for a through-the-curb connection. A
removable patch plate covers both the openings.
ERV
The ERV [Energy Recovery Ventilation] is a separate air han-
dler that attaches to the exhaust end of the 25-40T Millen-
nium packaged rooftop unit. The ERV is shipped separately
and assembled to the Millennium at the jobsite. An 'ERV' Mil-
lennium is shipped with an end configuration and electric
hookups designed to mate with the ERV. This option is avail-
able only with the Simplicity control, and no other power
exhaust option can be supplied if an ERV is selected.
The ERV incorporates a rotating heat exchange wheel and a
pair of exhaust blowers. It exhausts return air through the
wheel, capturing the thermal energy of the exiting hot or cold
air as it passes. As the wheel rotates, the incoming airstream,
pulled through by the supply fan, regains that energy.
The Millennium ERV has a terminal block and mating con-
nectors to simplify hooking up the two systems. The controls
of both units are factory set to interact properly. Power for the
ERV blower motors and controls is provided through the Mil-
lennium unit. The Millennium /ERV dataplate information
includes the ERV electrical load.
The Millennium Simplicity control has parameters for the
ERV; ref. the parameter list. When economizer and ERV
options are selected on the same unit, the Simplicity control
and the ERV have specific connections and internal rules for
that operation.
Also refer to the ERV Installation Instructions packaged with
the ERV.
Use care to avoid damage when drilling holes for
the disconnect mounting.
When connecting electrical power and control wir-
ing to the unit, waterproof connectors MUST BE
USED so that water or moisture cannot be drawn
into the unit during normal operation. The above
waterproofing conditions will also apply when
installing a field-supplied disconnect switch.
Waterproof connections MUST be used to ensure
that water cannot penetrate the roof or roof curb.

102777-YIM-E-0206
16 Unitary Products Group
GAS HEATING
GAS PIPING
Proper sizing of gas piping depends on the cubic feet per
hour of gas flow required, specific gravity of the gas and the
length of run. National Fuel Gas Code Z223.1-Latest Edition
should be followed in all cases unless superseded by local
codes or gas company requirements. Refer to Table 10.
The heating value of the gas may differ with locality. The
value should be checked with the local gas utility.
NOTE: There may be a local gas utility requirement specify-
ing a minimum diameter for gas piping. All units
require a 1-1/4 inch pipe connection at the entrance
fitting. Line should not be sized smaller than the
entrance fitting size.
GAS CONNECTION
The gas supply line should be routed within the space and
penetrate the roof at the gas inlet connection of the unit.
Refer to Fig. 13 -- 16 to locate the access opening. Typical
supply piping arrangements are shown in Figure 5.
Gas piping recommendations:
1. A drip leg and a ground joint union must be installed in
the gas piping.
2. When required by local codes, a manual shut-off valve
will have to be installed outside of the unit.
3. Use wrought iron or steel pipe for all gas lines. Pipe dope
should be applied sparingly to male threads only.
4. All piping should be cleaned of dirt and scale by ham-
mering on the outside of the pipe and blowing out the
loose particles. Before initial start-up, be sure that all of
the gas lines external to the unit have been purged of air.
5. The gas supply should be a separate line and installed in
accordance with all safety codes as prescribed under
Limitations. After the gas connections have been com-
pleted, open the main shutoff valve admitting normal gas
pressure to the mains. Check all joints for leaks with
On VAV units with gas fired furnace, ALL INDIVID-
UAL ROOM DAMPER BOXES MUST BE CON-
TROLLED FULL OPEN DURING HEATING
OPERATION TO ENSURE PROPER AIRFLOW
OVER THE FURNACE. A control contact between
D1 and D2 on TB3 is provided for the damper box
interlock. This contact is normally open, thus is
closed during heating operation.
TABLE 10: PIPE SIZES
LENGTH IN
FEET
NOMINAL IRON PIPE, SIZE
1-1/4 IN.1
1. Maximum capacity of pipe in cubic feet of gas
per hour (based upon a pressure drop of 0.3 inch
water column and 0.6 specific gravity gas.
1-1/2 IN.12 IN.1
10 1,050 1,600 3,050
20 730 1,100 2,100
30 590 890 1,650
40 - 760 1,450
50 - - 1,270
60 - - 1,150
70 - - 1,050
80 - - 990
FIGURE 6 - TYPICAL GAS PIPING CONNECTION
Natural gas may contain some propane. Propane,
being an excellent solvent, will quickly dissolve
white lead or most standard commercial com-
pounds. Therefore, a special pipe dope must be
applied when wrought iron or steel pipe is used.
Shellac base compounds such as Gaskolac or
Stalastic, and compounds such as Rectorseal #5,
Clyde's or John Crane may be used.

102777-YIM-E-0206
Unitary Products Group 17
soap solution or other material suitable for the purpose.
NEVER USE A FLAME
6. The furnace and its individual manual shut-off valve must
be disconnected from the gas supply piping system dur-
ing any pressure testing of that system at test pressures
in excess of 0.5 psig.
7. A 1/8 inch N.P.T. plugged tapping, accessible for test
gage connection, must be installed immediately
upstream of the gas supply connection to the furnace.
VENT AND COMBUSTION AIR
NOTE: All the hoods and hardware are shipped within the
evaporator section. Each hood must be properly
attached to the furnace doors to assure proper
operation and compliance with CSA/ETL safety cer-
tification. (Refer to Figure 7 and 8)
The products of combustion are discharged horizontally
through hooded openings in the gas heat access doors.
233 & 466 MBH HEAT
(Figure 7)
1. Remove the shipping covers that are attached to the
heat section door covering the flue outlets.
2. Locate the flue which is shipped in the evaporator sec-
tion.
3. Place the flue over the flue outlet with the diverter angles
facing up toward the top of the unit and attach with
screws provided.
4. Refer to the Gas Furnace Operation Instruction in the
Start-up Section of this manual for further instructions.
699 MBH HEAT
(Figure 8)
1. Remove the shipping covers that are attached to the
heat section door covering the flue outlets.
2. Locate the flue duct extensions and flue which are
shipped between the evaporator and filter section.
Disconnect gas piping from unit when leak testing
at pressures greater than 0.5 psig. Pressures
greater than 0.5 psig will cause gas valve damage
resulting in a hazardous condition. If gas valve is
subjected to pressure greater than 0.5 psig, it must
be replaced.
FIGURE 7 - VENT AND COMBUSTION AIR
HOODS
H E A T S E C T I O N D O O R
S H I P P I N G L A B E L S
( R E M O V E S H I P P I N G
L A B E L S P R I O R T O
V E N T I N S T A L L A T I O N )
V E N T F L U E A S S Y .
C O M B U S T I O N A I R I N L E T
E X H A U S T V E N T O U T L E T
FIGURE 8 - 699 MBH HEAT VENT
FIGURE 9 - FLUE EXTENSION
I N D S H I E L D
R E M O V E
S H I P P I N G
P L A T E S
O U T E R D O O R P A N E L
G A S H E A T S E C T I O N
F L U E D U C
T
F L U E E X T E N S I O N

102777-YIM-E-0206
18 Unitary Products Group
3. Place the flue extension (Figure 9) on the flue duct of
each furnace section and attach with screws provided.
4. Place the flue in position with the diverter angles facing
up toward the top of the unit and attach with screws pro-
vided.
5. Place the wind shield over the louvers on the right side of
the burner access door and attach with screws provided.
6. Refer to the Gas Furnace Operation Instructions in the
Start-up Section of this manual for further information.
ELECTRIC HEAT
Units with electric heat are fully wired and operational when
shipped. Constant volume units are designed for two equal
steps of capacity for 80 and 108 kWH heat; 40 kW heat is one
step only. VAV units are one full step at full heat capacity.
HOT WATER HEAT
The YORK Millennium units (25, 30, and 40 Ton sizes) can be
furnished with a YORK hot water coil as the heat source. One
or two row coil units will be factory installed in the heating
section.
NOTE: The hot water control valve will not be provided. The
installer will need to purchase a hot water control
valve, to connect the hot water piping and power
wiring at the job site for the hot water heat section to
be operational.
NOTE: For all hot water coils the entering water tempera-
ture should not exceed 200°F.
The hot water coil is located downstream of the supply air fan
and just above the supply air opening in the bottom of the
unit.
Refer to Tables 58 through 66 and Figures 36 through 49 for
flow rate and capacity.
FIGURE 10 - CLEARANCES
60"
REAR 60"
FRONT
60"
ENDS
10'
60"
ENDS
REQUIRED CLEARANCES
LEFT
RIGHT
REAR
FRONT
TOP
60"
60"
60"
60"
10'
* Right is the side with access to the Electrical / Gas Controls.
*is the side with the Condenser Coils
NOTE: DO NOT use the unit roof to support any type of
structure or bracing.
Front
DO NOT use hot water coils as steam coils under
any circumstances.
All piping, control valves, and wiring that is field
installed must be properly insulated and conform
to all local and national codes.

102777-YIM-E-0206
Unitary Products Group 19
PIPING CONNECTIONS
The hot water pipping must enter the unit through the floor of
the heat section compartment. The access doors to the com-
partment are gasketed so the compartment can be sealed.
However, as added protection for water leakage into the
space, the piping access holes should be sealed with a heat
resistant mastic Figure 11 shows the location of the compart-
ment and piping connections.
STEAM HEAT
The YORK Millennium units (25, 30 and 40 Ton sizes) can be
furnished with a YORK single row steam coil. YORK steam
coils are a factory installed option.
There are no provisions in the coil or control
sequence to prevent freezing of condensate. The
control valve, piping and field installed wiring con-
nections are particularly vulnerable because they
are installed in the vestibule outside of the condi-
tioned air stream. The installing party will be
responsible for properly insulating and installing
power and control wiring, to the actuator and pip-
ing.
In one row hot water coil systems DO NOT exceed
a 40 gallons per minute flow rate.
In two row hot water coil systems Do Not exceed a
80 gallons per minute flow rate
Condensate will freeze on the control valve and
piping if they are not properly insulated. Insulating
the control valve and piping is the responsibility of
the installing party.
Piping access holes should be sealed with a heat
resistant mastic to prevent damage to equipment.
DO NOT use tin based solder. Brazing with tin
based solder could cause equipment damage or
possible injury to tenets of the structure that is
being conditioned.
FIGURE 11 - HOT WATER PIPING CROSS-SEC-
TION
FIGURE 12 - STEAM PIPING CROSS-SECTION
H O T W A T E R
C O I L
C O N D E N S I N G
S E C T I O N
I N L E T 2 " )
O U T L E T 2 " )
CL
2 . 5 5 "
8 . 3 8 "
2 . 2 5 "
1 1 . 8 8 "
26"
1 5 . 8 "
8 8 . 7 5 "
H E A T S E C T I O N
C O M P A R T M E N T
( 1 O R 2 R O W )
O U T S I D E O F
BASE RAIL
STEAM
C O I L
C O N D E N S I N G
S E C T I O N
O U T L E T 1 1 / 2 " )
CL
2 . 5 5 "
8 . 3 8 "
26"
1 5 . 8 " I N L E T 2 " )
8 "
9 "
H E A T S E C T I O N
C O M P A R T M E N T
8 8 . 7 5 "
T O P V I E W
O U T S I D E O F
B A S E R A I L

102777-YIM-E-0206
20 Unitary Products Group
NOTE: The steam control valve, power and control wiring to
the actuator of the valve is the responsibility of the
installing party.
PIPING CONNECTIONS
Refer to Tables 54 through 57 and Figures 50 and 51 for flow
rate and capacity.
The steam piping must enter the unit through the floor of the
heat section compartment. The access doors to the compart-
ment are gasketed so the compartment can be sealed. How-
ever, as added protection for condensate leakage into the
space, the piping access holes should be sealed with a heat
resistant mastic. The following figure illustrates the location of
the compartment and piping connections.
STATIC PRESSURE CONTROL PLASTIC TUBING
On units with inlet guide vanes (IGV's) and variable fre-
quency drives on the supply blower and/or power exhaust
fans, pressure sensing tubing must be field supplied and
installed from differential pressure switches or transducers to
the locations in the building or ductwork where a constant
pressure is desired, and to the atmosphere.
The supply air discharge static pressure switch or transducer
is located in the blower compartment on the heat section par-
tition panel. Plastic tubing (1/4") must be run from the high
pressure tap of the transducer to a static pressure tap (field
supplied) in the supply duct located at a point where constant
pressure is desired. Tubing must also be run between the low
pressure tap of the transducer to atmospheric pressure.
EXHAUST STATIC PRESSURE
If a modulating power exhaust is installed, there will be a
building pressure sensor (BPS) in the control box directly
below the Millennium Simplicity. This ± .25 0-5VDC trans-
ducer sends a building pressure signal to the control. A sens-
ing tube must be installed from a representative location in
the building to the HI power of the transducer.
Changing the adjustment is done to the building pressure
parameter in the control.
All piping and control valves, and wiring that is
field installed must be properly insulated and con-
form to all local and national codes.
There are no provisions in the coil or control
sequence to prevent freezing of condensate. The
control valve, piping and field installed wiring con-
nections are particularly vulnerable because they
are installed in the vestibule outside of the condi-
tioned air stream. The installing party will be
responsible for properly insulating and installing
power and control wiring, to the actuator and pip-
ing.
DO NOT use steam coils as hot water coils under
any circumstances.
In steam coil systems, the steam pressure shall
not exceed 15 PSI.
Piping access holes should be sealed with a heat
resistant mastic to prevent damage to equipment.
DO NOT use tin based solder. Brazing with tin
based solder could cause equipment damage or
possible injury to tenets of the structure that is
being conditioned.
Do not run plastic tubes in the supply or return air
ducts as air movement could cause erroneous
sensing. If tubes penetrate bottom of unit be sure
openings are sealed against air and water leak-
age.