MILLENNIUM TM CENTRIFUGAL LIQUID CHILLERS OPERATING & MAINTENANCE Supersedes: Nothing Form 160.49-O2 (1296) 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 27385A W ARNING SYSTEM CONTAINS REFRIGERANT UNDER PRESSURE.
TABLE 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 .......
FORM 160.
SECTION 1 DESCRIPTION OF SYSTEM AND FUNDAMENTALS OF OPERATION COMPRESSOR CONTROL CENTER MOTOR DISCHARGE LINE 27385A PRE-ROTATION VANE ACTUATOR COOLER 27382A OIL RESERVOIR/ PUMP CONDENSER 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.
FORM 160.49-O2 design conditions. However, 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 for variation in load (See Fig. 2. Detail A).
SECTION 2 MICROCOMPUTER CONTROL CENTER 26879A LD00953 FIG. 3 – MICROCOMPUTER CONTROL 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.
FORM 160.49-O2 INTRODUCTION The YORK MicroComputer Control Center is a microprocessor based control system for R-22 or R134a centrifugal chillers. It controls the leaving 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.
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 STATUS 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.
FORM 160.49-O2 DISPLAY READS CONDENSER PRESS. EVAPORATOR PRESS. EVAP. PRESS. (BRINE) HOP TRANSDUCER LOP TRANSDUCER DISCHARGE TEMP. OIL TEMP. = = = = = = = LEAVING CONDENSER WATER TEMP. ENTERING CONDENSER WATER TEMP. < 6.8 PSIG, < 50 PSIG, < 25 PSIG, < 59.1 PSIG, < 23.2 PSIG, < 20.3°F; < 20.3°F; or > 300 PSIG or > 125 PSIG or > 100 PSIG or > 314.9 PSIG or > 271.8 PSIG > 226.4°F > 226.4°F XX.X PSIG XX.X PSIG XX.X PSIG XX.X PSIG XX.X PSIG XXX.X°F XXX.X°F = < 8.4°F; > 134.1°F XXX.X°F = < 8.
To Display CONDENSER LIQUID TEMPERATURES (Field Installed Option Package): Use CONDENSER LIQUID TEMPS display key as described above to produce the following alphanumeric display message: COND LEAVING = XXX.X°F; RETURN = XXX.X°F NOTE: If the condenser liquid thermistors are not connected, or both thermistors are “out of range”, the display will blank when this key is pressed. To Initiate a PRINT to Printer: Press the PRINT key to initiate a printout to an optional printer.
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 displays 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.
DISPLAYING SYSTEM SETPOINTS The currently programmed Setpoint values can be viewed at any time (see page 22) in SERVICE, LOCAL or REMOTE operating mode as follows: • Press and release the appropriate Setpoint key – the message will be displayed for 2 seconds. 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.
FORM 160.49-O2 TUE START = 05:00 AM STOP = 07:00 PM 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 START = 05:00 AM STOP = 01:00 PM HOL START = 00:00 AM STOP = 00:00 PM To Display UNDERVOLTAGE setpoints: (Solid State Starter Applications Only) Press SSS MOTOR CURRENT/VOLTS key in PROGRAM mode to display the selected voltage range. One of the following messages will be displayed.
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 follows to enter system setpoints. (Refer to Fig. 5.) 1. Press ACCESS CODE key. 2. ENTER VALID ACCESS CODE _ _ _ _ is displayed. 3. Using ENTRY keys, enter 9 6 7 5. 4. As each digit is entered, the characters Y O R K are displayed. NOTE: If digits other than 9 6 7 5 are entered, Y O R K is still displayed.
FORM 160.49-O2 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 any Energy Management System is applied, this value must be entered into the Energy Management System. Refer to previous explanation or REMOTE/RESET TEMP RANGE, page 11. 2.
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 value. 3. Press and release ENTER key. PROGRAM MODE, SELECT SETPOINT message is displayed. LD00957 FIG.
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 displayed: SUN START = XX:XX AM, STOP = XX:XX AM 6. Use the ADVANCE DAY / SCROLL key with procedure 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. 2.
To Enter HOLIDAY Setpoint: (Refer to Fig. 11.) 1. Press and release HOLIDAY setpoint key. The following program prompt message is displayed: S_ M_ T_ W_ T_ F_ S_ HOLIDAY NOTED BY r 2. Press and release ADVANCE DAY/SCROLL key to move cursor to the day that you wish to designate as a holiday. 3. Press and release r entry key. An r will appear next to the selected day. 4.
FORM 160.49-O2 SERVICE KEYS LD00963 FIG. 13 – KEYPAD – SERVICE KEYS LOCATION The Service keys are provided for the service technician’s use when performing routine maintenance or when troubleshooting the system. The WARNING RESET and PRE-ROTATION VANES keys are enabled in SERVICE mode only. The remainder of the Service keys are enabled in SERVICE, LOCAL or REMOTE mode. PRE-ROTATION VANES KEYS If chiller is equipped with the REFRIGERANT LEVEL CONTROL (and EPROM version C.02F(T).
OTHER SERVICE KEYS WARNING RESET – Press and release this key to reset any “WARNING” or “STATUS” message that can be reset with this key, unless the condition still exists. To reset any cycling or warning message, place the Control Center in SERVICE mode and press WARNING RESET key. To reset any safety shutdown message, press WARNING RESET key in SERVICE mode with the COMPRESSOR switch in the STOP/RESET position. MANUAL OIL PUMP – This key is operational in any mode.
FORM 160.49-O2 NO. 6 ACTUAL POS = XX MILS; REF = YY MILS – ACTUAL POS is the distance between the high speed thrust collar and the proximity probe that is used to measure the position. REF is the reference position established at time of compressor manufacture. NO. 7 HIGH SPEED DRAIN TEMP = XXX.X °F – Temperature of oil in high speed drain line. To hold any of the above messages, press the DISPLAY DATA key, then press the DISPLAY HOLD key.
7. Press PROGRAM key. 8. PROGRAM MODE, SELECT SETPOINT is displayed. 11. Press ADVANCE DAY key to scroll to desired mode. Each time this key is pressed, a different mode is displayed as above: 12. When the desired mode is displayed, press ENTER key. 9. Press MODE key. 10. The mode that has been previously selected will be displayed as follows: 13. PROGRAM MODE, SELECT SETPOINT is displayed. 14. Press ACCESS CODE key to exit PROGRAM mode and terminate access to PROGRAM mode.
FORM 160.49-O2 Therefore: (100%) (50% x 200) = 100A = Vanes stop opening (104%) (50% x 200) = 104A = Vanes driven toward close position. SYSTEM RUN – AUTO VANES Displayed when the chiller is running, the MicroComputer Control Center is in SERVICE mode, and the vanes are operating in AUTO mode. SYS READY TO START – VANES HOLDING Displayed when the chiller is running and the operator has pressed the vanes HOLD key on the keypad.
at 265 PSIG (R-22); 180 PSIG (R-134a). When the condenser pressure falls to 245 PSIG (R-22); 160 PSIG (R-134a), the vanes will be permitted to open. SYSTEM RUN – PRESSURE STATUS initial start-up). The status message consists of the day and time of shutdown, cause of shutdown, and type of restart required. Upon pressing STATUS key, System Shutdown Message will be displayed for 2 seconds and then return to SYSTEM SHUTDOWN – PRESS STATUS Displayed when the chiller is running.
FORM 160.49-O2 will be displayed if the Micro Board is configured for AUTO-RESTART AFTER POWER FAILURE. The Micro Board is factory set for manual restart after power failure. To convert it to auto-restart after power failure, remove one of the two-pin program jumpers from the cloth bag located inside the Control Center and place it on the terminals labeled “Auto R” (J60) on the Micro Board. MON XX:XX AM – POWER FAILURE The chiller is shut down because there has been a power interruption or failure.
has increased to 265 PSIG (R-22); 180 PSIG (R-134a). System will be allowed to restart when pressure decreases to 205 PSIG (R-22); 120 PSIG (R-134a). Pressure is sensed by a High Pressure (HP) safety control that is located on a mounting bracket above the oilpump starter located on the condenser. This message is prompted by the opening of the HP safety control contacts. To restart chiller, press COMPRESSOR switch to the STOP/RESET position and then to the START position.
FORM 160.49-O2 chiller, press COMPRESSOR switch to STOP/RESET position and then to START position. VANE MOTOR SWITCH OPEN The chiller is shut down because a system-start sequence has been initiated, but the pre-rotation vanes are not fully closed. MON XX:XX AM – STARTER MALFUNCTION DETECTED The chiller is shut down because the Control Center has detected a motor-current value greater than 15% FLA for 10 seconds minimum anytime when the compressor-start signal is not energized.
or failed to achieve the minimum required starting linevoltage. Refer to explanation under “System Setpoints – SSS Motor Current/Volts”, page 11. The system will automatically restart when all phases of line voltage increase to the minimum required starting voltage. MON XX:XX AM – HIGH LINE VOLTAGE (Solid State Starter applications only) Chiller is shut down because the voltage in any phase of line voltage has increased above the over-voltage threshold for 20 consecutive seconds.
FORM 160.49-O2 IMPORTANT!!!: Although this message is generally indicative of a defective proximity probe, it is possible that the compressor has been damaged. If the high speed thrust bearing is not inspected by a qualified service technician prior to starting the chiller, further severe compressor damage could result. The chiller cannot be restarted until the “Special Reset Procedure” in YORK Service manual, Form 160.49-M3 is performed by a qualified service technician.
SECTION 3 SYSTEM OPERATING PROCEDURES WARNING OIL HEATERS If the oil heater is de-energized during a shutdown period, they must be energized for 12 hours prior to starting compressor, or remove all oil and recharge compressor with new oil. (See “Charging Unit With Oil”, page 43.) NOTE: The oil heater is thermostatically controlled and remains energized as long as the fused disconnect switch to the starter or turbo-modulator is energized.
FORM 160.49-O2 START-UP 1. If the chilled water pump is manually operated, start the pump. The Control Center will not allow the chiller to start unless chilled liquid flow is established through the unit. (A field supplied chilled water flow switch is required.) If the chilled liquid pump is wired to the MicroComputer Control Center the pump will automatically start, therefore, this step is not necessary. 2. To start the chiller, press the COMPRESSOR START switch.
SYSTEM STARTING & SHUTDOWN SEQUENCE OPERATOR INITIATED (NOTE 2) LD00952 NOTES: 1. REF. MICROBOARD PROGRAM JUMPER JP6 2. REF. MICROBOARD PROGRAM JUMPER JP4 FIG.
FORM 160.49-O2 be no lower than the value determined by referring to the formula below: Min. ECWT = LCHWT—C RANGE + 5 + ( 15 x % LOAD 100 ) where: ECWT = entering condensing water temperature LCHWT = leaving chilled water temperature C RANGE = condensing water temperature range At start-up, the entering condenser water temperature may be as much as 25°F colder than the standby return chilled water temperature.
YORK office. Automatic data logging is possible by connecting the optional printer and programming the DATA LOGGER function; refer to Form 160.49-N7. An accurate record of readings serves as a valuable reference for operating the system. Readings taken when a system is newly installed will establish normal conditions with which to compare later readings.
FORM 160.49-O2 4. Inspect and service electrical components as necessary. 5. Perform chemical analysis of system. • Motor Phase Current Unbalance (Solid State Starter Unit only) • Proximity sensor • Faulty Prox. Probe • Open Drain Thermocouple NEED FOR MAINTENANCE OR SERVICE If the system is malfunctioning in any manner or the unit is stopped by one of the safety controls, consult the “Operation Analysis Chart”, pages 47 through 48 of this instruction.
period. EPROM version C.02F(T).12 or later provides a 10 minute coastdown period. The compressor, condenser water, and cooling tower fans will stop automatically. The oil pump will continue to run for coastdown period. The oil pump will then stop automatically. Once stopped, the SYSTEM COASTDOWN display will be replaced by SYSTEM READY TO START . 2. Stop the chilled water pump (if not wired into the MicroComputer Control Center, in which case it will shut off automatically simultaneously with the oil pump.
FORM 160.49-O2 SECTION 4 SYSTEM COMPONENTS DESCRIPTION MICROCOMPUTER CONTROL CENTER DISCHARGE COMPRESSOR SUCTION ADAPTER MOTOR SUPPORT & COVER DUAL RELIEF VALVES MOTOR COOLER 27385A DEHYDRATOR REFRIGERANT CHARGING VALVE SIGHT GLASSES FRONT VIEW DISCHARGE LINE OIL PUMP STARTER 27382A OIL RESERVOIR/ PUMP CONDENSER FIG.
GENERAL The YORK Model YK Millennium Centrifugal Liquid Chiller is completely factory-packaged including cooler, condenser, compressor, motor, lubrication system, MicroComputer Control Center, and all interconnecting unit piping and wiring. The initial charge of refrigerant and oil is supplied for each unit. Oil is shipped in containers with the chiller. Refrigerant is shipped to the jobsite in cylinders at the time of installation.
FORM 160.49-O2 FIG.
oil pump sooner, depress the MANUAL OIL PUMP key again. On shutdown of the system for any reason, the oil pump operates and continues to run for 150 seconds. The system cannot restart during that time interval. OIL HEATER During long idle periods, the oil in the compressor oil reservoir tends to absorb as much refrigerant as it can hold, depending upon the temperature of the oil and the pressure in the reservoir. As the oil temperature is lowered, the amount of refrigerant absorbed will be increased.
FORM 160.49-O2 age to the Micro Board that represents this level (0% = empty; 100% = full). Under program control, the Micro Board modulates a variable orifice to control the condenser refrigerant level to a programmed setpoint. Other setpoints affect the control sensitivity and response. These setpoints must be entered at chiller commissioning by a qualified service technician. Only a qualified service technician may modify these settings. Manual operation of the refrigerant level control can be selected.
SECTION 5 OPERATIONAL MAINTENANCE OIL RETURN SYSTEM The oil return system continuously maintains the proper oil level in the compressor oil sump. (See Figs. 18 & 19.) return line to rotor support and inlet end of the dehydrator. 2. Remove the dehydrator. Refer to Fig. 19. High pressure condenser gas flows continuously through the eductor inducing the low pressure, oil rich liquid to flow from the evaporator, through the dehydrator to the compressor sump. 3. Assemble the new filter-drier. 4.
FORM 160.49-O2 THE OIL CHARGE The nominal oil charge for the compressor is 20 gal., type “F” for R-22 application or type “K” for R-134a application. plate. (See Fig. 20.) Do not tighten the connection at the charging valve until after the air is forced out by pumping a few strokes of the oil pump. This fills the lines with oil and prevents air from being pumped into the system. New YORK Refrigeration oil must be used in the centrifugal compressor.
TABLE 1 – CAUSES OF NORMAL AND SAFETY SYSTEM SHUTDOWNS IN ACCORDANCE WITH THE MICROCOMPUTER CONTROL, CENTER DISPLAY SHUTDOWN CAUSE CONTROL CENTER DISPLAY GOVERNING CONTROL FUNCTION PROGRAMMED SETPOINTS BY OPERATOR START-UP OF SYSTEM AFTER SHUTDOWN MON. 10:00 AM Low Water Temp. Autostart Low Water (LWT) MON. 10:00 AM Flow Switch Autostart Flow Switch MON. 10:00 AM System Cycling Autostart MON.
MON. 10:00 AM YORK INTERNATIONAL Low Evap. Pressure Low Evap. Pressure Transducer (LEP) LEP external control (Brine units only) MON. 10:00 AM Low Evap. Pressure Brine MON. 10:00 AM Low Oil Pressure Low Oil Pressure Transducer (OP) MON. 10:00 AM High Pressure High Pressure Safety Control (HP) 54.3 54.4 PSIG (R-22) PSIG (R-22) 25 25.
TABLE 1 – CAUSES OF NORMAL AND SAFETY SYSTEM SHUTDOWNS IN ACCORDANCE WITH THE MICROCOMPUTER CONTROL, CENTER DISPLAY SHUTDOWN CAUSE CONTROL CENTER DISPLAY DAY OF WEEK TIME OF DAY CAUSE OF SHUTDOWN MON. 10:00 AM Oil Pressure Transducer Error Vane Motor Switch Open MON. 10:00 AM Starter Malfunction Detected MON. 10:00 AM Program Initiated Reset Replace RTC IC chip Reprogram Setpoints Low Oil Temperature YORK INTERNATIONAL MON. 10:00 AM MON. 10:00 AM Faulty Discharge Temp. Sensor MON.
FORM 160.49-O2 TABLE 2 – OPERATING ANALYSIS CHART RESULTS POSSIBLE CAUSE REMEDY 1. SYMPTOM: ABNORMALLY HIGH DISCHARGE PRESSURE Temperature difference between liquid refrigerant out and water off condenser higher than normal. Air in condenser. High discharge pressure. Condenser tubes dirty or . scaled Clean condenser tubes. Check water conditioning. High condenser water temperature. Reduce condenser water inlet temperature. (Check cooling tower and water circulation.
TABLE 2 – OPERATING ANALYSIS CHART (Continued) RESULTS POSSIBLE CAUSE REMEDY 6. SYMPTOM: USUALLY HIGH OIL PRESSURE DEVELOPS WHEN OIL PUMP RUNS Unusually high oil pressure is displayed when the oil pressure display key is pressed when the oil pump is running. High oil pressure. Transducer defective. Relief valve is misadjusted. Replace low or high oil pressure transducer. Adjust external relief valve. 7.
FORM 160.49-O2 SECTION 7 MAINTENANCE RENEWAL PARTS For any required Renewal Parts, refer to “Parts Lists” shown in “Reference Instructions”, page 2. lide torch or electronic leak detector can be used to detect any leaks too small to be found by the soap test. To test with R-22, proceed as follows: CHECKING SYSTEM FOR LEAKS LEAK TESTING DURING OPERATION The refrigerant side of the system is carefully pressure tested and evacuated at the factory.
TABLE 3 – SYSTEM PRESSURES *GAUGE ABSOLUTE INCHES OF MERCURY (HG) BELOW ONE STANDARD ATMOSPHERE PSIA MILLIMETERS OF MERCURY (HG) MICRONS 0 10.24" 22.05" 25.98" 27.95" 28.94" 29.53" 29.67" 29.72" 29.842" 29.882" 29.901" 29.917" 29.919" 29.9206" 29.921" 14.696 9.629 3.865 1.935 .968 .481 .192 .122 .099 .039 .019 .010 .002 .001 .0002 0 760. 500. 200. 100. 50. 25. 10. 6.3 5. 2. 1.0 .5 .1 .05 .
FORM 160.49-O2 VACUUM DEHYDRATION To obtain a sufficiently dry system, the following instructions have been assembled to provide an effective method for evacuating and dehydrating a system in the field. Although there are several methods of dehydrating a system, we are recommending the following, as it produces one of the best results, and affords a means of obtaining accurate readings as to the extent of dehydration.
REFRIGERANT CHARGING To avoid the possibility if freezing liquid within the cooler tubes when charging an evacuated system, only refrigerant vapor from the top of the drum or cylinder must be admitted to the system pressure until the system pressure is raised above the point corresponding to the freezing point of the cooler liquid. For water, the pressure corresponding to the freezing point is 57.5 PSIG for R22 or 8.54 PSIG for R-134a (at sea level).
FORM 160.49-O2 HANDLING REFRIGERANT FOR DISMANTLING AND REPAIRS If it becomes necessary to open any part of the refrigerant system for repairs, it will be necessary to remove the charge before opening any part of the unit. MEGGING THE MOTOR While the main disconnect switch and compressor motor starter are open, meg the motor as follows: 2. If readings fall below shaded area, remove external leads from motor and repeat test. 1.
TEMPERATURE – °F FIG. 24 – MOTOR STATOR TEMPERATURE AND INSULATION RESISTANCES Minimum Insulation Resistance vs.
FORM 160.49-O2 CONDENSERS AND COOLERS GENERAL TUBE FOULING Maintenance of condenser and cooler shells is important to provide trouble free operation of the chiller. The water side of the tubes in the shell must be kept clean and free from scale. Proper maintenance such as tube cleaning, and testing for leaks, is covered on the following pages.
recommends the use of this type of organization. The Dow Industries Service Division of the Dow Chemical Company, Tulsa, Oklahoma, with branches in principal cities is one of the most reliable of these companies. TESTING FOR COOLER AND CONDENSER TUBE LEAKS Cooler and condenser tube leaks in R-22 or R-134a systems may result in refrigerant leaking into the water circuit, or water leaking into the shell depending on the pressure levels.
FORM 160.49-O2 COMPRESSOR Maintenance for the compressor assembly consists of checking the operation of the oil return system and changing the dehydrator, checking and changing the oil, checking and changing the oil filters, checking the operation of the oil heater, checking the operation of the oil pump, and observing the operation of the compressor.
SECTION 8 PREVENTIVE MAINTENANCE It is the responsibility of the owner to provide the necessary daily, monthy and yearly maintenance requirements of the system. IMPORTANT – If a unit failure occurs due to improper maintenance during the warranty period; YORK will not be liable for costs incurred to return the system to satisfactory operation. In any operating system it is most important to provide a planned maintenance and inspection of its functioning parts to keep it operating at its peak efficiency.
FORM 160.49-O2 eductor should be checked for any foreign particles that may be obstructing the jet. ELECTRICAL CONTROLS 1. All electrical controls should be inspected for obvious malfunctions. YORK INTERNATIONAL 2. It is important that the factory settings of controls (operation and safety) not be changed. If the settings are changed without YORK’s approval, the warranty will be jeopardized. 3. A 5-11 year life battery is part of the RTC-Real Time Clock. To replace, refer to page 29.
P.O. Box 1592, York, Pennsylvania USA 17405-1592 Copyright © by York International Corporation 1997 Form 160.49-O2 (1296) Supersedes: Nothing Subject to change without notice.
