York YK M3, MH, M3 G4, HC User Manual

MILLENNIUM

CENTRIFUGAL LIQUID CHILLERS

OPERATING & MAINTENANCE

MODEL YK M3 M3 G4 THRU YK S6 S4 J2 (STYLE C)

R-22 (COOLING ONLY)

MODEL YK LB LB G4 THRU YK SE SC J4 (STYLE C)

R-134a (COOLING ONLY)

WITH MICROCOMPUTER CONTROL CENTER

PART #371-01200-010, 371-01200-011 & 371-01200-015

FOR ELECTRO-MECHANICAL STARTER,

SOLID STATE STARTER & VARIABLE SPEED DRIVE

Supersedes: Nothing

Form 160.49-O2 (1296)

ARNINGARNING

ARNING

ARNINGARNING

SYSTEM CONTAINS REFRIGERANT UNDER PRESSURE.

SERIOUS INJURY COULD RESULT IF PROPER PROCEDURES ARE NOT FOLLOWED WHEN SERVICING SYSTEM. ALL SERVICE WORK SHALL BE PERFORMED BY A QUALIFIED SERVICE TECHNICIAN IN ACCORDANCE WITH Y ORK INSTALLATION/OPERA TION MANUAL.

27385A

ABLE OF CONTENTSABLE OF CONTENTS

ABLE OF CONTENTS

ABLE OF CONTENTSABLE OF CONTENTS

Page

SECTION 1 – Description of System and

Fundamentals of Operation ......................................... 4

SECTION 2 – MicroComputer Control Center ...................................... 6

SECTION 3 – System Operating Procedures ..................................... 30

SECTION 4 – System Component Description .................................. 37

SECTION 5 – Operational Maintenance ............................................. 42

SECTION 6 – Trouble Shooting........................................................... 44

SECTION 7 – Maintenance ................................................................. 49

SECTION 8 – Preventive Maintenance............................................... 58

REFERENCE INSTRREFERENCE INSTR

REFERENCE INSTR

REFERENCE INSTRREFERENCE INSTR

DESCRIPTION FORM NO.

Solid State Starter – Operation & Maintenance 160.46-OM3.1 V ariable Speed Drive – Operation 160.00-O1 Installation 160.49-N5 Installation and Operation of Printers 160.49-N7 Wiring Diagram – Unit with Electro-Mechanical Starter 160.49-PW7 Wiring Diagram – Field Connections (E-M Starter) 160.49-PW10 Wiring Diagram – Field Control Modifications 160.49-PW13 Wiring Diagram – Control Center with SS Starter 160.49-PW8 Wiring Diagram – Field Connections (SS Starter) 160.49-PW11 Wiring Diagram – Solid State Starter 160.49-PW14 Wiring Diagram – Unit with Solid State Starter 160.49-PW8 Wiring Diagram – Unit with Variable Speed Drive 160.49-PW9 Wiring Diagram – Field Connections (V.S.D.) 160.49-PW12 Wiring Diagram – Variable Speed Drive 160.49-PW15

UCTIONSUCTIONS

UCTIONS

UCTIONSUCTIONS

2 YORK INTERNA TIONAL

R-22 UNITS

YK N2 N1 H1 – CX C

CONDENSER CODE M3, M4, N3, N4, P3, P4, Q3, Q4, R3, R4, S3, S4

COOLER CODE M3, M4, N3, N4, P3, P4, P5, P6, Q3, Q4, Q5, Q6, R3, R4, R5, R6, S5, S6

NOMENCLATURE

DESIGN LEVEL (C)

POWER SUPPLY – for 60 HZ 5 for 50 HZ

COMPRESSOR CODE G4, H0, H1, H2, J1, J2

FORM 160.49-O2

MOT OR CODE:

{

60 HZ 50 HZ CH CX 5CE 5CT CJ CY 5CF 5CU CK CZ 5CG 5CV CL CA 5CH 5CW CM CB 5CI 5CX CN DA 5CJ 5DA CP DB 5CK 5DB CR DC 5CL 5DC CS DD 5CM 5DD CT DE 5CN 5DE CU DF 5CO 5OF CV DH 5CP 5OG CW DJ 5CQ 5OH

5CR 5OJ 5CS

MODEL

R-134a

YK NB PB H1 – CX C

CONDENSER CODE LB, LC, MB , MC, NB, NC, PB, PC, QB, QC, RB, RC, SB, SC

COOLER CODE LB, LC, MB , MC , NB, NC, PB , PC, PD , PE, QB, QC, QD, QE, RB, RC, RD , RE, SD, SE

DESIGN LEVEL (C)

POWER SUPPLY – for 60 HZ 5 for 50 HZ

COMPRESSOR CODE G4, H0, H1, H2, J1, J2, J3, J4

MOT OR CODE:

{

60 HZ 50 HZ CH CX 5CE 5CT CJ CY 5CF 5CU CK CZ 5CG 5CV CL CA 5CH 5CW CM CB 5CI 5CX CN DA 5CJ 5DA CP DB 5CK 5DB CR DC 5CL 5DC CS DD 5CM 5DD CT DE 5CN 5DE CU DF 5CO 5DF CV DH 5CP 5DG CW DJ 5CQ 5DH

5CR 5OJ 5CS

MODEL

Y ORK INTERNA TIONAL 3

CONTROL CENTER

SECTION 1

DESCRIPTION OF SYSTEM AND FUNDAMENTALS OF OPERA TION

COMPRESSOR

MOTOR

PRE-ROT ATION

DISCHARGE LINE

27385A

COOLER

VANE ACTUA T OR

FIG. 1 – MODEL YK MILLENNIUM CHILLER

SYSTEM OPERATION DESCRIPTION (See Fig. 2)

The YORK Model YK Millennium Chiller is commonly applied to large air conditioning systems, but may be used on other applications. The chiller consists of an open motor mounted to a compressor (with integral speed increasing gears) condenser, cooler and flow control chamber.

The chiller is controlled by a modern state of the art MicroComputer Control Center which monitors its operation. The Control Center is programmed by the operator to suit job specifications. Automatic timed startups and shutdowns are also programmed to suit nighttime, weekends, and holidays. The operating status, temperatures, pressures, and other inf ormation pertinent to operation of the chiller are automatically displayed and read on a 40 character alphanumeric message display. Other displays can be observed by pressing the keys as labeled on the Control Center. The chiller with the MicroComputer Control Center is applied with an electro-mechanical starter, YORK Solid State Starter (optional), or Variable Speed Drive (optional).

OIL RESERVOIR/ PUMP

CONDENSER

In operation, a liquid (water or brine to be chilled) flows through the cooler, where boiling refrigerant absorbs heat from the water. The chilled liquid is then piped to fan coil units or other air conditioning terminal units, where it flows through finned coils, absorbing heat from the air. The warmed liquid is then returned to the chiller to complete the chilled liquid circuit.

The refrigerant vapor, which is produced by the boiling action in the cooler, flows to the compressor where the rotating impeller increases its pressure and temperature and discharges it into the condenser. W ater flowing through the condenser tubes absorbs heat from the refrigerant vapor, causing it to condense. The condenser water is supplied to the chiller from an external source, usually a cooling tower . The condensed refrigerant drains from the condenser into the flow control chamber, where the flow restrictor meters the flow of liquid refrigerant to the cooler to complete the refrigerant circuit.

The major components of a chiller are selected to handle the refrigerant which would be evaporated at full load

27382A

4 YORK INTERNA TIONAL

7619A(D)

DET AIL A – COMPRESSOR PRER O TATION V ANES

FORM 160.49-O2

design conditions. Howev er, most systems will be called upon to deliver full load capacity for only a relatively small part of the time the unit is in operation.

CAPACITY CONTROL

The major components of a chiller are selected for full load capacities, therefore capacity must be controlled to maintain a constant chilled liquid temperature leaving the cooler. Prerotation vanes (PRV), located at the entrance to the compressor impeller, compensate f or variation in load (See Fig. 2. Detail A).

The position of these vanes is automatically controlled through a lever arm attached to an electric motor located outside the compressor housing. The automatic adjustment of the vane position in effect provides the performance of many different compressors to match various load conditions from full load with vanes wide open to minimum load with vanes completely closed.

COMPRESSOR

DISCHARGE

DISCHARGE BAFFLE

CONDENSER

SUB-COOLER

FLOW CONTROL ORIFICE

PREROT A TION V ANES (See Detail A)

SUCTION

COOLER

ELIMINA TOR

LD00924

FIG. 2 – REFRIGERANT FLOW-THRU CHILLER

Y ORK INTERNA TIONAL 5

OIL COOLER

SECTION 2

MICROCOMPUTER CONTROL CENTER

26879A

LD00953

FIG. 3 – MICROCOMPUTER CONTR OL CENTER AND KEYPAD

NOTE: This instruction covers operation of chillers equipped with Electro-Mechanical or Solid State Starters. If chiller

is equipped with Variable Speed Drive, Form 160.00-O1 is to be used in conjunction with this manual.

WARNING

This equipment generates, uses and can radiate radio frequency energy and if not installed and used in accordance with the instructions manual, may cause interference to radio communications . Operation of this equipment in a residential area is likely to cause interference in which case the user at his own expense will be required to take whatev er action ma y be required to correct the interf erence .

Additionally , any electronic equipment can generate EMI (electromagnetic interf erence) which, depending upon the installation and magnitude, may affect other electronic equipment. The amount of EMI generated is determined by the source inductance, load inductance, and circuit impedances. Responsibility for assuring the satisfactory operation of other equipment included in the same power source as the YORK equipment rests solely with the user. YORK disclaims any liability resulting from any interference or for the correction thereof.

6 YORK INTERNA TIONAL

INTRODUCTION

FORM 160.49-O2

The YORK MicroComputer Control Center is a microprocessor based control system for R-22 or R134a centrifugal chillers. It controls the lea ving chilled water temperature via pre-rotation vane control and has the ability to limit motor current via control of the pre-rotation vanes. Further, it is compatible with YORK Solid State Starter (optional), Variable Speed Drive (optional), and electromechanical starter applications.

A keypad mounted on the front of the Control Center (see Fig. 3) allo ws the operator to displa y system operating parameters on a 40 character alphanumeric display that is part of the keypad. These readings are displayed via “Display” keypad as follows: (In the English mode; temperatures in °F, pressures in (PSIG) (in the metric mode, temperatures in °C, Pressures in KP a).

If unit is equipped with EPROM version C.02F(T).12 or later, the Control Center can be equipped with an optional Chinese language display, either as a field retrofit or factory supplied option on new units. This display mounts on the control center door, directly above the standard display. Both the standard and Chinese display will be present, providing displa y messages simultaneously in both English and Chinese language.

The system setpoints (see Fig. 3) are operator entered on the front control center Setpoints keypad. These setpoints can also be displayed on the 40 char acter alphanumeric display. The system setpoints are:

• CHILLED LIQUID TEMPERATURE (LCWT)

• % CURRENT LIMIT

• PULLDOWN DEMAND LIMIT

• CLOCK (TIME-OF-DAY)

• DAILY SCHEDULE (7 DAY TIME-CLOCK PROGRAMMING)

• HOLIDAY

• REMOTE RESET TEMPERATURE RANGE

• DATA LOGGER

• CONDENSER REFRIGERANT LEVEL

The cause of all system shutdowns (safety or cycling) is preserved (until the system is reset or restarts) in the microcomputer’s memory for subsequent viewing on the keypad display. The operator is continually advised of system operating conditions by various background and warning messages. The keypad contains special service keys for use by the service technician when performing system troubleshooting.

The Control Center must be configured for Chinese display by a qualified service technician. Instructions are contained in YORK service manual, Form 160.49-M3.

• CHILLED LIQUID TEMPERATURES – LEAVING AND RETURN

• REFRIGERANT PRESSURES – EVAPORATOR AND CONDENSER

• DIFFERENTIAL OIL PRESSURE

• CONDENSER LIQUID TEMPERATURES – OPTIONAL FIELD INSTALLED – LEAVING AND RETURN

• OPTIONS

• PRINT *

• HISTORY PRINT *

• MOTOR CURRENT IN % OF FULL LOAD AMPS

• SA TURA TION TEMPERA TURES – EV APORATOR AND CONDENSER

• DISCHARGE TEMPERATURE

• OIL TEMPERATURE

• HIGH & LOW OIL PRESSURE TRANSDUCER PRESSURE

• SOLID ST ATE STARTER MOTOR CURRENT / VOLTS (When Supplied)

• CONDENSER REFRIGERANT LEVEL

The MicroComputer Control Center is designed to be compatible with most Energy Management Systems

(EMS) in use today. The standard design allows for the following EMS interface:

1. Remote Start

2. Remote Stop

3. Remote LCWT Setpoint (Pulse Width Modulated signal)

4. Remote Current Limit Setpoint (Pulse Width Modulated signal)

5. A “Remote Mode Ready to Start” Status Contacts

6. Safety Shutdown Status Contacts

7. Cycling Shutdown Status Contacts

As an enhancement to the standard EMS features, an optional card file with plug-in printed circuit boards is available. These optional cards will accept a remote LCWT 0 to 10°F or 0 to 20°F setpoint offset and/or remote current limit setpoint interface from three user input choices.

1. 4-20mA

2. 0-10VDC

* These ke ys provide a print-out when the customer connects a com-

patible printer to the Micro Board RS-232 serial port. (See Form

160.49-N7.)

Y ORK INTERNA TIONAL 7

3. Contact Closures

CONTROL CENTER

The Control Center front panel layout consists of five key groups, one switch and a 1 line by 40 character alphanumeric vacuum fluorescent display: (see Fig. 3.)

CHARACTERISTIC DISPLAY – The alphanumeric vacuum fluorescent display is located to the right of the ST ATUS key . All messages, parameters, set points, and data can be viewed at this location. The main communications between the operator or service technician and the MicroComputer Control Center occurs on this display.

DISPLAY – Provide a direct readout of each monitored parameter on the alphanumeric display.

ENTRY – These keys are used to enter the values for the operator programmed setpoints. These k eys are used in conjunction with the Setpoint keys while in PRO-

GRAM mode.

SETPOINTS – These keys are used as follows:

1. To view each setpoint, in any mode , or

2. To select the individual setpoints that are prog rammed by the operator in PR OGRAM mode only.

Pressing the appropriate key enables the operator to program that setpoint pressing the Entry keys.

SERVICE– Included in this group of keys are those functions that are only relevant to servicing the chiller .

Typically, these keys would not be used for daily chiller operation.

ACCESS CODE – Permits operator to access the program.

PROGRAM – Permits operator to program the Control Center.

MODE – P ermits operator to check what mode the Control Center is presently in (LOCAL, REMOTE or SER- VICE).

1. Service – allows manual PRV control with visual display readout of PRV operation.

2. Local – allows manual compressor start from the COMPRESSOR switch on the Control Center front.

3. Program – allows operator programming of system setpoints.

4. Remote – allows remote start, remote stop of compressor and remote reset of LCWT and % current limit.

COMPRESSOR-START, RUN, STOP/RESET SWITCH – This 3-position rocker s witch is used to start (except in REMO TE mode), stop/run/reset the system.

OPERATION

DISPLA YING SYSTEM PARAMETERS

The Display keys are used to display selected monitored parameters as follows: (Refer to Fig. 3.)

• Press and release the appropriate Display ke y – the message will be displayed f or 2 seconds.

– or –

• Press and hold the appropriate Display key – the message will be displayed and updated every 0.5 seconds until the Display ke y is released.

– or –

• Press and release appropriate Display key , then press and release the DISPLAY HOLD key – the message

8 YORK INTERNA TIONAL

will be displayed and updated every 2 seconds until the DISPLAY HOLD key is again pressed and re- leased, or 10 minutes have elapsed, whiche ver comes first.

NOTE: If the display actually displays X’s, then the

monitored parameter is out of normal operating range (refer to Fig. 4). If the “English/Metric” jumper is installed on the Micro Board, all temperatures are displayed in degrees F ahrenheit (°F) and all pressures are displayed in pounds per sq. inch gauge (PSIG) except oil pressure which is displayed in pounds per sq. inch diff erential (PSID). If the “English/Metric” jumper is not installed, all temperatures are displayed in degrees Centigrade (°C) and all pressures are displayed in Kilo-Pascals (kPa).

FORM 160.49-O2

DISPLAY

READS

CONDENSER PRESS. = < 6.8 PSIG, or > 300 PSIG XX.X PSIG EVAPORATOR PRESS. = < 50 PSIG, or > 125 PSIG XX.X PSIG EVAP. PRESS. (BRINE) = < 25 PSIG, or > 100 PSIG XX.X PSIG HOP TRANSDUCER = < 59.1 PSIG, or > 314.9 PSIG XX.X PSIG LOP TRANSDUCER = < 23.2 PSIG, or > 271.8 PSIG XX.X PSIG DISCHARGE TEMP. = < 20.3°F; > 226.4°F XXX.X°F OIL TEMP. = < 20.3°F; > 226.4°F XXX.X°F

LEAVING CONDENSER WATER TEMP. ENTERING CONDENSER WATER TEMP.

LEAVING EVAPORATOR = < 0°F XX.X°F WATER TEMP. = > 81.1°F XX.X°F

ENTERING EVAPORATOR = < .1°F XX.X°F WATER TEMP. = > 93°F XX.X°F

= < 8.4°F; > 134.1°F XXX.X°F

FIG. 4 – SYSTEM PARAMETERS – OUT OF

RANGE READINGS

To Display CHILLED LIQUID TEMPERATURES:

______ PSID = (HOP – LP) – OFFSET PRESSURE OFFSET PRESSURE: Pressure differential between

the HOP transducer and LOP transducer outputs during a 3 second period beginning 10 seconds after the start of “START SEQUENCE INITIATED”. During this time, the transducers will be sensing the same pressure and their outputs should indicate the same pressure. However, due to accuracy tolerances in transducer design, differences can exist. Therefore, to compensate for differences between transducers and assure differential pressure sensing accuracy, the OFF- SET PRESSURE is subtracted algebraically from the differential pressure. The offset pressure calculation will not be performed if either transducer is out-of-range. The offset value will be taken as 0 PSI in this instance.

To Display OPTIONS:

This key is not used.

NO OPTIONS INSTALLED

is displayed when this key is pressed.

Press CHILLED LIQUID TEMPS displa y key as de- scribed on page 7 to produce the following alphanumeric display message:

CHILLED LEA VING = XXX.X°F, RETURN = XXX.X°F

To Display REFRIGERANT PRESSURE:

Use REFRIGERANT PRESSURE display key as described on page 7 to produce the following alphanumeric display message:

EV AP = XXX.X PSIG; COND = XXX.X PSIG

To Display OIL PRESSURE:

Use OIL PRESSURE display key as described on page 7 to produce the following alphanumeric display message:

OIL PRESSURE = XXXX.X PSID

The differential pressure displayed is the pressure difference between the high side oil pressure transducer (output of oil filter) and the low side oil pressure transducer (compressor housing). Displayed value includes offset pressure derived from auto-zeroing during “START SEQUENCE INITIATED”. If either transducer is out-of-range, XX.X is displayed. Oil pressure is calculated as follows:

To Display SSS MOT OR CURRENT / VOLTS: (Solid State Starter Applications Only)

If chiller is equipped with a Y ORK Solid State Starter, use SSS MOTOR CURRENT / VOLTS key to dis- play 3-phase compressor motor current and 3-phase Solid State Starter input line voltage.

Continuously pressing this key will display the motor current and line voltage alternately. When used with the DISPLAY HOLD key, motor current and line voltage will alternately be displayed each time this key is pressed. The messages are as follows:

A AMPS = XXXX; B AMPS = XXXX; C AMPS = XXXX V A-B = XXXX; V B-C = XXXX; V C-A = XXXX

If chiller is not equipped with a Solid State Starter, this key produces the following message:

SOLID STATE STARTER NOT INSTALLED

In PROGRAM mode, this k ey is used to displa y the applicable line voltage range (200-208VAC, 220240V AC , 380VAC, 400V A C , 415V A C , 440-480V A C, 500-600V AC, Supply V oltage Range Disab led). The correct line voltage range is programmed at the YORK factory and is checked by the service technician at start-up. For security reasons, a special access code is required to program the line voltage range. The line voltage range is used to determine a low line voltage threshold for cycling shutdown. Refer to “System Setpoints” for Trip/Reset values.

Y ORK INTERNA TIONAL 9

To Display CONDENSER LIQUID TEMPERATURES

(Field Installed Option Package):

Use CONDENSER LIQUID TEMPS display key as described above to produce the follo wing alphan umeric display message:

Computer Control Center”, page 14. However, the purpose of the OPERATING HOURS key is to display the total accumulated chiller run time. Therefore, the operating hours should not be arbitrarily reset.

SYSTEM SETPOINTS

COND LEAVING = XXX.X°F; RETURN = XXX.X°F

NOTE: If the condenser liquid thermistors are not con-

nected, or both thermistors are “out of range”, the display will blank when this k e y is pressed.

To Initiate a PRINT to Printer:

Press the PRINT key to initiate a printout to an optional printer. When the key is pressed,

PRINT ENABLE

is displayed.

Refer to “MicroComputer Control Center – System Status Printers” instruction, Form 160.49-N7 for details of the optional printers.

To Display MOTOR CURRENT:

Press the % MOTOR CURRENT display key as described above to display motor current as a percent of Full Load Amps (FLA). The message is as follows:

MOTOR CURRENT = XXX% FLA

The system setpoints may be programmed by the system operator. The Setpoints keys are located on the Control Center keypad (see Fig. 3). To program, see “Programming System Setpoints”, page 14. The following is a description of these setpoints (with the English/ Metric jumper installed on the Micro Board):

CHILLED LIQUID TEMP – This key displays the leaving chilled water temperature (LCWT) setpoint in degrees Fahrenheit. If not progr ammed, the default value is 45°F. See “Programming System Setpoints”, page 15).

NOTE: If an Energy Management System is interfaced

to the Control Center for the purpose of remote LCWT setpoint reset, then the operator-programmed chilled liquid temperature will be the base or lowest setpoint av ailable to the Energy Management System (EMS). This chilled liquid temperature value must also be entered into the EMS. Further, any subsequent change to this value must also be entered into the EMS.

% CURRENT LIMIT – This key displays the maximum value of motor current permitted by its programmed setting. The value is in terms of percent of Full Load Amps (FLA). If not programmed, the def ault value is 100%. (See “Programming System Setpoints”, page 15.)

NOTE: • Liquid-Cooled Solid State Starter Applications

– the % Motor Current displayed is the highest of three line currents divided by the programmed chiller FLA value x 100%.

• Electro-Mechanical Starter Applications – the % Motor Current displayed is the highest of the three line currents.

If chiller is equipped with a YORK Solid State Starter, the system FLA is also displayed. This value is programmed by the f actory and should nev er be changed. The Micro Board uses this value to calculate and display the % motor current parameter that is displayed when the % MOT OR CURRENT display ke y is pressed. Also, proper current limit control depends on the correctly programmed FLA value. For security reasons, a special access code is required to program the FLA value. It should only be changed by a service technician.

To Display OPERATING HOURS and STARTS COUNTER:

Use the OPERA TING HOURS ke y as described on page 8, to produce the following message:

OPER. HOURS = XXXXX; START COUNTER = XXXXX

PULL DOWN DEMAND – This function is used to provide energy savings following the chiller start-up. This key displays a programmable motor current limit and a programmable period of time. Operation is as follows: Whenever the system starts, the Pull Down Demand Limit is maintained for the programmed time, then the current limit control returns to % current limit setpoint.

NOTE: The operating hours and starts counter can be

reset to zero. Ref er to “Progr amming the Micro-

The maximum permitted motor current is in terms of % FLA. The duration of time that the current is limited is in

10 YORK INTERNA TIONAL

FORM 160.49-O2

terms of minutes (to a maximum of 255). If not programmed, the default value is 100% FLA for 00 minutes. (See “Programming Systems Setpoints”, page 16.) Thus, no pull down demand limit is imposed following system start, and the % current limit setpoint is used.

CLOCK – This key displa ys the day of the week, time of day and calendar date. If not programmed, the default value is

SUNDAY 12:00 AM 1/1/92 .

(See “Programming System Setpoints”, page 16.)

DAIL Y SCHEDULE – This key displays the programmed daily start and stop times, from Sunday thru Saturday plus Holiday. If desired, the Control Center can be programmed to automatically start and stop the chiller as desired. This schedule will repeat on a 7-day calendar basis. If the Daily Schedule is not progr ammed, the default value is 00:00 AM start and stop times for all da ys of the week and the holiday. (Note that the system will not automatically start and stop on a daily basis with these default values because 00:00 is an “Impossible” time for the Micro Board. See “Programming System Setpoints”, page 17.) Finally, one or more days in the week can be designated as a holiday (see description under HOLIDAY setpoint) and the Control Center can be programmed (usually Daily Schedule setpoint) to automatically start and stop the chiller on those days so designated. The operator can override the time clock at any time using the COMPRESSOR switch.

For additional information on remote LCWT reset, refer to Form 160.49-PW13.

NOTE: If an Energy Management System is interfaced

to the Control Center for the purpose of remote LCWT setpoint reset, then the operator programmed REMOTE RESET TEMP RANGE value determines the maximum value of temperature reset controlled by the Energy Management System.

DATE LOGGER – This key is used when an optional printer is connected to the MicroComputer Control Center. Refer to Form 160.49-N7 for operation instructions.

SSS MOT OR CURRENT/VOLTS – This key is used on Solid State Starter applications only. Although this is a display key, it is used to program the applicable AC power line voltage range (380VAC, 400VAC, 415VAC, 440-480VAC, 550-600VAC). The MicroComputer Control Center uses this entry to determine the under-voltage and overvoltage shutdown threshold. For each line voltage category, there is an undervoltage and overvoltage shutdown threshold. If the AC po wer line v oltage exceeds these thresholds for 20 continuous seconds, the chiller shuts down and displays

MON 10:00 AM LOW LINE VOLTAGE

– or –

Note that if only a start time is entered for a particular day, the compressor will not automatically stop until a scheduled stop time is encountered on a subsequent day.

HOLIDAY – This key indicates which da ys in the upcoming week are holidays. On those designated days, the chiller will automatically start and stop via the holiday start and stop times programmed in the DAIL Y SCHED- ULE setpoint. It will do this one time only and the f ollowing week will rev ert to the normal daily schedule for that day.

REMOTE / RESET TEMP RANGE – This key displays the maximum offset of remote LCWT setpoint reset. This offset is either 10° or 20°F as programmed. When in the REMOTE mode, this v alue is added to the operator programmed CHILLED LIQUID TEMP setpoint and the sum equals the temperature range in which the LCWT can be reset. For example, if the operator programmed CHILLED LIQUID TEMP setpoint is programmed with a value of 10°F, then the CHILLED LIQUID TEMP setpoint can be remotely reset over a range of 46°F to 56°F (46 + 10 = 56). If not prog rammed, the default value for this parameter is 20°F.

MON 10:00 AM HIGH LINE V OLTAGE

This overvoltage and undervoltage protection can be disabled. Ref er to chart below:

LOW / HIGH LINE VOLTAGE TRIP / RESET VALUES

COMPRESSOR

MOT OR

SUPPL Y VOL TA GE

RANGE – (V)

380 305 331 415 414 400 320 349 436 435

415 335 362 454 453 440-480 370 400 524 523 550-600 460 502 655 654

Supply V oltage

Range Disabled

LOW LINE VOL TAGE HIGH LINE V O LTAGE

OPERA TING POINT OPERATING POINT

CUTOUT -(V) CUTIN-(V) CUTOUT -(V) CUTIN-(V)

(

ON FALL) (ON RISE) (ON RISE) (ON FALL)

NONE 0 NONE 0

For security reasons, a special access code is required to program the supply voltage range. The supply voltage range is programmed at the factory and should only be changed by a service technician.

Y ORK INTERNA TIONAL 11

DISPLAYING SYSTEM SETPOINTS

The currently programmed Setpoint values can be viewed at any time (see page 22) in SER VICE, LOCAL or REMOTE operating mode as follo ws:

• Press and release the appropriate Setpoint key – the message will be displayed f or 2 seconds.

– or –

If chiller is equipped with a YORK Solid State Starter, the message is:

CURRENT LIMIT = XXX % FLA; *MTR CUR = 000 FLA

NOTE: On Solid State Starter applications, this value is

programmed at the YORK factory . A special access code is required.

• Press and hold the appropriate Setpoint key – the message will be displayed as long as the key is pressed.

– or –

• Press and release the appropriate Setpoint key , then press and release the DISPLA Y HOLD k ey . The message will be displayed until the DISPLAY HOLD key is again pressed and released, or 10 minutes have elapsed, whichever comes first.

To Display CHILLED LIQUID TEMP Setpoint:

Use CHILLED LIQUID TEMP setpoint key as de- scribed on page 10 to produce the following message:

LEAVING SETPOINT = XX.X °F

NOTE: The value displayed is the actual LCWT setpoint.

For example , the value display ed in LOCAL

PROGRAM modes is that which is oper ator programmed. The v alue displayed in the REMOTE mode is that base setpoint with added temperature reset by an Energy Management System, via remote LCWT setpoint (PWM signal) if a remote reset signal was received within 30 minutes.

To Display PULL DOWN DEMAND Setpoint:

Use PULL DOWN DEMAND setpoint key as de- scribed on page 10 to produce the following message:

SETPOINT = XXX MIN @ XX % FLA XXX MIN LEFT

To Display CLOCK Setpoint (Time of Day):

Use CLOCK setpoint key as described above to produce the following message:

TODAY IS DAY XX:XX AM/PM 1/1/92

To Display DAILY SCHEDULE Setpoints:

• Press and hold the DAILY SCHEDULE setpoint key. The chiller start and stop times for each day of the

week are sequentially display ed, beginning with Sunday and ending with Holida y. The displa y will continuously scroll until the DAILY SCHEDULE key is re- leased.

– or –

• Press and release the DAIL Y SCHEDULE setpoint k ey . Then press and release the DISPLA Y HOLD k ey . The

To Display % CURRENT LIMIT Setpoint:

Use % CURRENT LIMIT setpoint key as described above to produce the f ollowing message:

CURRENT LIMIT = XXX % FLA

chiller start and stop times for each day of the week are sequentially displayed beginning with Sunda y and ending with Holiday . The display will continuously scroll until the DISPLAY HOLD key is again pressed and released, or 10 minutes have elapsed, whichever comes first.

NOTE: The value display ed is the actual % current limit

setpoint. For example, the value displayed in LOCAL or PROGRAM mode is that which is operator programmed. The value displayed in the REMOTE mode is that which has been pro- grammed by the Energy Management System via the remote current limit setpoint input.

The display message for DAILY SCHEDULE will scroll in the following sequence:

SUN START = 08:30 AM STOP = 06:00 PM MON START = 05:00 AM STOP = 07:00 PM

12 YORK INTERNA TIONAL

TUE START = 05:00 AM STOP = 07:00 PM

FORM 160.49-O2

WED START = 05:00 AM STOP = 07:00 PM THU START = 05:00 AM STOP = 07:00 PM FRI START = 05:00 AM STOP = 07:00 PM SAT STAR T = 05:00 AM STOP = 01:00 PM HOL START = 00:00 AM STOP = 00:00 PM

To Display HOLIDAY Setpoints:

Use HOLIDAY setpoint key as described in the be- ginning of this section to produce the following message:

S_ M_ T_ W_ T_ F_ S_ HOLIDAY NOTED BY *

NOTE: On the days that are designated by an *, the

chiller will automatically start and stop per the holiday schedule established in D AIL Y SCHED- ULE setpoints.

To Display UNDERVOLTAGE setpoints: (Solid State Starter Applications Only)

Press SSS MOTOR CURRENT/V OL TS key in PRO- GRAM mode to display the selected voltage range. One of the following messages will be displa yed.

SUPPLY VOLTAGE RANGE 380

– or –

SUPPLY VOLTAGE RANGE 400

– or –

SUPPLY VOLTAGE RANGE 415

– or –

SUPPLY VOLTAGE RANGE 440-480

– or –

SUPPLY VOLTAGE RANGE 550-600

– or –

To Display REMOTE RESET TEMP RANGE Setpoint:

Use REMOTE RESET TEMP RANGE setpoint ke y as described above to produce the following message:

REMOTE RESET TEMP RANGE = 10°F

– or –

REMOTE RESET TEMP RANGE = 20°F

To Display DATA LOGGER setpoints:

Refer to Y ORK, F orm 160.49-N7 for operation of this key .

SUPPLY VOLTAGE RANGE DISABLED

A special access code is required to program the Supply Voltage Range. The Supply Voltage Range is programmed at the factory and check ed at system start-up. (Note to service technician: Refer to programming instructions in Service Instruction, Form 160.49-M3.)

Y ORK INTERNA TIONAL 13

PROGRAMMING

THE MICROCOMPUTER CONTROL CENTER

PROGRAMMING SYSTEM SETPOINTS

The system setpoints can be entered at any time . . . . .

even when the system is running. Proceed as f ollows to enter system setpoints. (Ref er to Fig. 5.)

1. Press ACCESS CODE key .

ENTER VALID ACCESS CODE _ _ _ _

3. Using ENTRY keys, enter 9 6 7 5.

4. As each digit is entered, the characters Y O R K are displayed.

is displayed.

NOTE: If digits other than 9 6 7 5 are entered,

YORKis still displayed.

NOTE: For ease in remembering the code, note that

the letters YORKcorrespond to the digits 9675on a telephone dial

5. Press ENTER key. NOTE: If digits other than 9675 w ere entered in step

No. 4,

INVALID ACCESS CODE

is displayed when the ENTER key is pressed. If this occurs, enter the correct access code (9675) and proceed.

ACCESS TO PROGRAM KEY AUTHORIZED

is displayed.

NOTE: Unless terminated by pressing the ACCESS

CODE key again, the operator will have access to the PROGRAM key for 10 minutes. When 10 minutes have elapsed, access to PROGRAM key will be automatically disab led and the operator must return to step No. 1 to gain access.

7. Press PROGRAM key .

PROGRAM MODE, SELECT SETPOINT

is displayed.

LD00954

FIG. 5 – KEYPAD – PROGRAMMING SYSTEM

SETPOINTS

9. Enter setpoints as detailed below. If you make a mistake when entering a value, press CANCEL k ey and then ENTER key . The display will re vert to the default values and the cursor will return to the first changeable digit. You can then proceed to enter the correct values. If the entered v alue exceeds acceptab le limits,

OUT OF RANGE – TRY AGAIN!

message will be displayed for 2 seconds, then the

PROGRAM MODE, SELECT SETPOINT

message will re-

appear.

10.When all the desired setpoints have been entered, press the ACCESS CODE key to exit PROGRAM mode and terminate access to PROGRAM mode.

ACCESS TO PROGRAM MODE DISABLED

is displayed. The Control Center will automatically return to LO-

CAL, REMOTE or SERVICE mode . . . . whichever

was last selected.

14 YORK INTERNA TIONAL

To enter CHILLED LIQUID TEMP Setpoint: (Refer to Fig. 6.)

1. Press and release CHILLED LIQUID TEMP setpoint key. The following program prompt message will be displayed:

LEAVING SETPOINT = XX.X °F (BASE)

(BASE) refers to the base or lowest setpoint available to an Energy Management System. If an y Energy Management System is applied, this value must be entered into the Energy Management System. Refer to previous explanation or REMO TE/RESET TEMP RANGE, page 11.

FORM 160.49-O2

2. Use ENTRY keys to enter desired v alue.

3. Press and release ENTER key.

PROGRAM MODE, SELECT SETPOINT

message is displayed.

To Enter % CURRENT LIMIT Setpoint: (Electro-Mechanical Starter , ref er to Fig. 7)

1. Press and release % CURRENT LIMIT setpoint key . The following program prompt message is displa yed:

CURRENT LIMIT = XXX% FLA

2. Use ENTRY k e ys to enter desired v alue .

3. Press and release ENTER key.

PROGRAM MODE, SELECT SETPOINT

message is displayed.

LD00955

FIG. 6 – KEYPAD – PROGRAMMING “LEAVING

CHILLED WATER TEMP” SETPOINT

3. Press and release ENTER key.

PROGRAM MODE, SELECT SETPOINT

message is displayed.

(Solid State Starter, ref er to Fig. 7)

1. Press and release % CURRENT LIMIT setpoint key . The following program prompt message is displa yed:

CURRENT LIMIT = XXX% FLA; MTR CUR = _ _ _ FLA

2. Use ENTRY k e ys to enter desired v alue . NOTE: Motor Current FLA value is entered by Y ORK

LD00956

factory and checked at system start-up. It cannot be changed without special access code. (Note to service technician: refer to

FIG. 7 – KEYPAD – PROGRAMMING “% CURRENT

LIMIT” SETPOINT

“Programming Instructions” in Service instruction, Form 160.49-M3.

Y ORK INTERNA TIONAL 15

To Enter PULL DOWN DEMAND Setpoint: (Refer to Fig. 8.)

1. Press and release PULL DOWN DEMAND setpoint key. The following program prompt message is displayed:

SETPOINT = XXX MIN @ XXX % FLA, XXX MIN LEFT

2. Use Entry keys to enter desired values. For explanation, see PULL DOWN DEMAND, page 12. Note that “XX min left” is not an operator entered v alue .

3. Press and release ENTER key.

PROGRAM MODE, SELECT SETPOINT

message is displayed.

LD00957

FIG. 8 – KEYPAD – PROGRAMMING “PULL DO WN

DEMAND” SETPOINT

To Enter CLOCK Setpoint: (Refer to Fig. 9.)

1. Assure Micro Board Program jumper J57 is in “CLKON” position.

2. Press and release CLOCK setpoint key. The f ollo w- ing program prompt message is displayed:

TOD AY IS MON 10:30 PM 1/1/92

3. Press ADVANCE DAY / SCROLL key until the pro- gram per day of week appears on the display.

4. Use Entry keys to enter proper time of day.

5. Press AM/PM key to change the AM to PM or vice versa.

6. Use Entr y keys to enter proper calendar date, (MONTH/DA Y/YR). If month and da y are single digit entries, precede the entry with “0”. For example, 02/04/88.

7. Press and release ENTER key.

PROGRAM MODE, SELECT SETPOINT

message is displayed.

LD00958

FIG. 9 – KEYPAD – PROGRAMMING “CLOCK”

SETPOINT

16 YORK INTERNA TIONAL

FORM 160.49-O2

To Enter DAILY SCHEDULE Setpoint: (Refer to Fig. 10.)

1. Press and release DAILY SCHEDULE setpoint key. The following prompt message is displa yed:

SUN START = XX:XX AM, STOP = XX:XX AM

2. If the displayed start and stop time is not the desired schedule, enter the desired start and stop times as follows:

a. If you do not want the chiller to automatically start

and stop on this day, press CANCEL key.

b. Use the Entry keys to enter desired hours and

minutes start time.

c. If necessary, press the AM/PM ke y to change “AM”

to “PM” or vice versa.

d. Use the Entry keys to enter desired hours and

minutes stop time.

e. If necessary , press the AM/PM key to change “AM”

to “PM” or vice versa.

3. Press and release ADV ANCE D A Y/SCROLL ke y. The following prompt message is displa yed:

6. Use the ADV ANCE DAY / SCROLL key with proce- dure in Step 2. To enter start and stop times for remainder of the week plus a holiday schedule if required.

7. Press the ENTER key.

PROGRAM MODE, SELECT SETPOINT

is displayed.

MON START = XX:XX AM, STOP = XX:XX AM

4. Enter the desired start and stop time per Step 2.

5. Press and release ADV ANCE D A Y/SCROLL ke y. The following prompt message is displa yed:

REPEAT MON SCHEDULE MON-FRI? YES = 1; NO = 0

a. If you press the 1 Entry key, Monday’s start and

stop time will be automatically entered for Tuesday through F riday.

– or –

b. If you press the 0 Entry key, Tuesday through Fri-

day can be programmed with different start and stop times.

LD00959

FIG. 10 – KEYPAD – PROGRAMMING “DAIL Y

SCHEDULE” SETPOINT

Y ORK INTERNA TIONAL 17

To Enter HOLIDAY Setpoint: (Refer to Fig. 11.)

1. Press and release HOLIDAY setpoint key. The fol- lowing program prompt message is display ed:

S_ M_ T_ W_ T_ F_ S_ HOLIDAY NOTED BY

2. Press and release ADV ANCE DAY/SCR OLL k ey to move cursor to the day that y ou wish to designate as a holiday .

3. Press and release r entry key. An r will appear next to the selected day.

4. After you have placed an r n ext to each of the da ys that you wish to designate a holiday, press ENTER key

PROGRAM MODE, SELECT SETPOINT

message is displayed. T o cancel all of the designated holidays: perform Step

1, press CANCEL key, and then press ENTER key.

PROGRAM MODE, SELECT SETPOINT

message is displayed. To cancel one of the designated holidays: perform

Step 1, press ADVANCE DAY / SCROLL key until the cursor appears to the right of the desired day, press the r key, then press the ENTER key.

LD00961

FIG. 11 – KEYPAD – PROGRAMMING “HOLIDAY”

SETPOINT

To Enter REMOTE/ RESET TEMP RANGE Setpoint: (Refer to Fig. 12.)

1. Press and release REMOTE/RESET TEMP RANGE setpoint key . The following program prompt message is displayed:

REMOTE TEMP SETPOINT RANGE = XX °F

2. Use Entry keys desired value (10 or 20).

3. Press and release ENTER key.

PROGRAM MODE, SELECT SETPOINT

message is displayed.

To Enter DA TA LOGGER Setpoint: Refer to F orm 160.49-N7 for operation of this k e y.

LD00962

FIG. 12 – KEYPAD – PROGRAMMING “REMO T E

RESET” TEMP RANGE

18 YORK INTERNA TIONAL

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