York YT Specifications

26874AMILLENNIUMCENTRIFUGAL LIQUID CHILLERSOPERATING & MAINTENANCE Supersedes: Nothing 1096 FORM 160.48-O1MODEL YT G0 A1 B1 thru YT L6 D8 F2 (STYL

10 YORK INTERNATIONALPULL DOWN DEMAND - This function is used to pro-vide energy savings following the chiller start-up. Thiskey displays a programmab

YORK INTERNATIONAL 11FORM 160.48-O1press and release the “DISPLAY HOLD” key. The mes-sage will be displayed until the “DISPLAY HOLD” keyis again press

12 YORK INTERNATIONALmon start = 05:00 am stop = 07:00 pmproduce the following message:TODAY IS DAY XX:XX AM/PM 1/1/89To Display DAILY SCHEDULE

YORK INTERNATIONAL 13FORM 160.48-O1PROGRAMMING THE MICROCOMPUTERCONTROL CENTER9. Enter setpoints as detailed below. If you make a mis-take when enteri

14 YORK INTERNATIONALTo enter CHILLED LIQUID TEMP Setpoint:(Refer to Fig. 7)1. Press and release “CHILLED LIQUID TEMP” setpointkey. The following prog

YORK INTERNATIONAL 15FORM 160.48-O1To Enter PULL DOWN DEMAND Setpoint:(Refer to Fig. 9)1. Press and release “PULL DOWN DEMAND”setpoint key. The follow

16 YORK INTERNATIONALTo Enter DAILY SCHEDULE Setpoint:(Refer to Fig. 11)FIG. 11 - KEYPAD - PROGRAMMING “DAILY SCHEDULE” SETPOINTFIG. 12 - KEYPAD - PR

YORK INTERNATIONAL 17FORM 160.48-O1To Enter REMOTE/RESET TEMP RANGE Setpoint:FIG. 13 - KEYPAD - PROGRAMMING “REMOTE RESET TEMP RANGE” SETPOINTFIG. 14

18 YORK INTERNATIONALSERVICE KEYSFIG. 15 - KEYPAD - SERVICE KEYS LOCATIONThe “SERVICE” keys are provided for the servicetechnician’s use when performi

YORK INTERNATIONAL 19FORM 160.48-O1trol circuitry is automatically placed in “AUTO” mode andthe vanes operate to control the leaving chilled watertemp

2 YORK INTERNATIONALTABLE OF CONTENTSSection 1: Description of System and Operational Fundamentals ...4Section 2: MicroComputer

20 YORK INTERNATIONALand it says that there have been 7 purges in the“Last Hour”, that means that there have been 7exhausts since 8:11 AM. If you do t

YORK INTERNATIONAL 21FORM 160.48-O1COMPRESSOR SWITCH(Refer to Fig. 15, page 18)This rocker switch is used to locally operate the com-pressor. It is us

22 YORK INTERNATIONALSYSTEM RUN – LOW PRESSURE LIMIT IN EFFECTDisplayed when the chiller is running and the evapora-tor pressure falls to 5.55 PSIA (R

YORK INTERNATIONAL 23FORM 160.48-O1SYSTEM SHUTDOWN – PRESS STATUSDisplayed when chiller is shut down on a cycling shut-down, safety shutdown (operator

24 YORK INTERNATIONALMON XX:XX AM – SYSTEM CYCLING – AUTOSTARTA remote command (computer relay contact or manualswitch) connected to the Remote/Local

YORK INTERNATIONAL 25FORM 160.48-O1rator Pressure (LEP, not included with standard ControlCenter) safety contacts have opened. The brine LEPsafety is

26 YORK INTERNATIONALFLA for 10 seconds minimum anytime when the com-pressor-start signal is not energized. To restart the chiller,press “COMPRESSOR”

YORK INTERNATIONAL 27FORM 160.48-O1MON XX:XX AM – HIGH LINE VO LTAG E(Solid State Starter Applications Only)Chiller is shut down because the voltage i

28 YORK INTERNATIONALSECTION 3SYSTEM OPERATING PROCEDURESFIG. 17 - MICROCOMPUTER CONTROL CENTER AND KEYPADWARNINGOIL HEATERSIf the oil heater is de-en

YORK INTERNATIONAL 29FORM 160.48-O1START-UP PROCEDUREPre-StartingPrior to starting the chiller observe the MicroComputerControl Center. Make sure the

YORK INTERNATIONAL 3FORM 160.48-O126874A28009AFIG. 1 - YT CHILLER WITH ELECTRO-MECHANICAL STARTERFIG. 2 - YT CHILLER WITH VARIABLE SPEED DRIVE

30 YORK INTERNATIONAL3. The 1R-1 contacts of the 1R start relay will remainopen for the first 30 seconds of oil pump operation.These contacts will clo

YORK INTERNATIONAL 31FORM 160.48-O1chilled water temperature. Cooling tower fan cyclingwill normally provide adequate control of the enteringcondenser

32 YORK INTERNATIONALAn optional status printer is available for this purposeor Fig. 20 shows a log sheet used by YORK personnelfor recording test dat

YORK INTERNATIONAL 33FORM 160.48-O1(amps) at E-M starter (or Variable Speed Drive), oron the Control Center display for Solid State Starterunits.8. Ch

34 YORK INTERNATIONALthis unit is to automatically remove the mixture ofnoncondensable gases and refrigerant from the top ofthe condenser, expel the n

YORK INTERNATIONAL 35FORM 160.48-O1for 150 seconds (6 min. if Micro Board jumper JP-4removed). The compressor, condenser water, andcooling tower fans

36 YORK INTERNATIONALcompressor load with quiet operation. Gears are inte-grally assembled in the compressor rotor support and areoil film lubricated.

YORK INTERNATIONAL 37FORM 160.48-O1the various bearings and gears in the event of a sys-tem shutdown due to power failure. The reservoir, lo-cated on

38 YORK INTERNATIONALLD00468FIG. 22 - SCHEMATIC DRAWING - YT COMPRESSOR LUBRICATION SYSTEM

YORK INTERNATIONAL 39FORM 160.48-O1SOLID STATE STARTER (OPTIONAL)The Solid State Starter is a reduced-voltage liquid cooledstarter that controls and m

4 YORK INTERNATIONALSECTION 1DESCRIPTION OF SYSTEM AND OPERATIONALFUNDAMENTALSing through the condenser tubes absorbs heat fromthe refrigerant vapor,

40 YORK INTERNATIONALNOTE: If digits other than the correct digits wereentered in step No. 4,day INVALID ACCESS CODEis displayed when the “ENTER”

YORK INTERNATIONAL 41FORM 160.48-O13. Using “entry” keys enter the appropriate accesscode per above description.4. As each digit is entered, the chara

42 YORK INTERNATIONALPurge CountFollowing a 1 hour bypass at start, purge exhausts arecounted and displayed in the above messages whilethe chiller is

YORK INTERNATIONAL 43FORM 160.48-O1FIG. 24 - SCHEMATIC OPERATIONAL DIAGRAMFIG. 25 - OIL RETURN SYSTEMFIG. 26 - ASSEMBLY OF DEHYDRATORLD00471LD00469LD0

44 YORK INTERNATIONALFIG. 27 - CHARGING OIL RESERVOIR WITH OILCHARGING THE UNIT WITH OILthe pump discharge connection to the oil chargingvalve (A) l

YORK INTERNATIONAL 45FORM 160.48-O1

46 YORK INTERNATIONALSECTION 6TROUBLE SHOOTINGTABLE 1 - CAUSES OF NORMAL AND SAFETY SYSTEM SHUTDOWNS IN ACCORDANCE WITH THE MICROCOMPUTER CONTROL

YORK INTERNATIONAL 47FORM 160.48-O1TABLE 1 - CAUSES OF NORMAL AND SAFETY SYSTEM SHUTDOWNS IN ACCORDANCE WITH THE MICROCOMPUTER CONTROL CENTER DISP

48 YORK INTERNATIONALTABLE 1 - CAUSES OF NORMAL AND SAFETY SYSTEM SHUTDOWNS IN ACCORDANCE WITH THE MICROCOMPUTER CONTROL CENTER DISPLAY - CONTINUE

YORK INTERNATIONAL 49FORM 160.48-O1TABLE 1 - CAUSES OF NORMAL AND SAFETY SYSTEM SHUTDOWNS IN ACCORDANCE WITH THE MICROCOMPUTER CONTROL CENTER DISP

YORK INTERNATIONAL 5FORM 160.48-O1FIG. 3 - REFRIGERANT FLOW THROUGH CHILLERFIG. 3 (DETAIL A) - COMPRESSOR PREROTATION VANES7619A(D)FLOW CONTROLCOMPRES

50 YORK INTERNATIONALTABLE 2 - OPERATING ANALYSIS CHARTRESULTS POSSIBLE CAUSE REMEDY 1. SYMPTOM: ABNORMALLY HIGH DISCHARGE PRESSURETemperature diffe

YORK INTERNATIONAL 51FORM 160.48-O1TABLE 2 - OPERATING ANALYSIS CHART - CONTINUEDRESULTS POSSIBLE CAUSE REMEDY 6. SYMPTOM: UNUSUALLY HIGH OIL PRESSU

52 YORK INTERNATIONALSECTION 7MAINTENANCERENEWAL PARTSFor any required Renewal Parts refer to Forms listed on page 2.CHECKING SYSTEM FOR LEAKSLEAK TES

YORK INTERNATIONAL 53FORM 160.48-O1BOILINGTEMPERATURESOF WATER °FFIG. 28 - EVACUATION OF CHILLER LD00473TABLE 3 - SYSTEM PRESSURES*GAUGE ABSOLUTEINCH

54 YORK INTERNATIONALthe source of hot water under pressure and the coolerhead drain connection, out the cooler vent connec-tion, into the condenser h

YORK INTERNATIONAL 55FORM 160.48-O1down keep a careful watch on the wet bulb indicator tem-perature, and do not let it fall below 35°F. If the tempera

56 YORK INTERNATIONALMEGGING THE MOTORWhile the main disconnect switch and compressor mo-tor starter and Variable Speed Drive both open, meg themotor

YORK INTERNATIONAL 57FORM 160.48-O1FIG. 31 - MOTOR STATOR TEMPERATURE AND INSULATION RESISTANCESLD00476

58 YORK INTERNATIONALCondenserIn a condenser, trouble due to fouled tubes is usuallyindicated by a steady rise in head pressure, over a pe-riod of tim

YORK INTERNATIONAL 59FORM 160.48-O1tube simultaneously and insert the exploring tubefor 5 seconds - this should be long enough to drawinto the detecto

6 YORK INTERNATIONALSection 2MICROCOMPUTER CONTROL CENTERNOTE: This instruction covers operation of chillers equipped with Electro-Mechanical or Solid

COOLER AND CONDENSERThe major portion of maintenance on the condenser andcooler will deal with the maintaining of the water side ofthe condenser and c

YORK INTERNATIONAL 7FORM 160.48-O1The system setpoints (see Fig. 4) are operator enteredon the front control center “Setpoints” keypad. Theseset point

8 YORK INTERNATIONALOPERATIONTo Display CHILLED LIQUID TEMPERATURES:Press “CHILLED LIQUID TEMPS” display key asdescribed above to produce the followi

YORK INTERNATIONAL 9FORM 160.48-O1FLA value x 100%.For Electro-Mechanical Starter Applications- the % of Motor Current displayed is the high-est of th