York MaxE YK Operating And Maintenance Download Page 25

FORM 160.73-O2 (605)

25

YORK INTERNATIONAL

SECTION 6

MAINTENANCE

RENEWAL PARTS

For any required Renewal Parts, refer to YORK Re new al 
Parts Unit Components Manual 160.73-RP1.

CHECKING SYSTEM FOR LEAKS

Leak Testing During Operation

The refrigerant side of the system is carefully pres sure 
tested and evacuated at the factory.

After the system has been charged, the system should 
be carefully leak tested with a R-134a compatible leak 
detector to be sure all joints are tight.

If any leaks are indicated, they must be repaired im-
 me di ate ly. Usually, leaks can be stopped by tightening 
fl are nuts or fl ange bolts. However, for any major re pair, 
the re frig er ant  charge  must  be  removed.  (See  “Han dling 
Re frig er ant  for  Dismantling  and  Repair”,  page  29.)

CONDUCTING R-22 PRESSURE TEST

With the R-134a charge removed and all known leaks 
re paired, the system should be charged with a small 
amount of R-22 mixed with dry nitrogen so that a ha 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:

  1. With no pressure in the system, charge R-22 gas into 

the system through the charging valve to a pres sure 
of 2 PSIG (14 kPa).

  2. Build up the system pressure with dry nitrogen to ap-

proximately 75 to 100 PSIG (517 to 690 kPa). To be 
sure that the con cen tra tion of refrigerant has reached 
all part of the sys tem, slightly open the oil charging 
valve and test for the presence of re frig er ant  with  a 
leak de tec tor.

  3. Test around each joint and factory weld. It is im por -

tant that this test be thoroughly and carefully done, 
spending as much time as necessary and using a good 
leak detector.

 4. To check for refrigerant leaks in the evaporator and 

con dens er, open the vents in the evaporator and con-
 dens er heads and test for the presence of refrigerant. 
If no refrigerant is present, the tubes and tube sheets 
may be considered tight. If refrigerant is detected at the 
vents, the heads must be removed, the leak located (by 
means of soap test or leak detector) and re paired.

EVACUATION AND DEHYDRATION OF UNIT

FIG. 11 – 

EVACUATION OF CHILLER

27385A(D)

LD00949

6

Summary of Contents for MaxE YK

Page 1: ...CENTRIFUGAL LIQUID CHILLERS Supersedes 160 73 O2 1202 Form 160 73 O2 605 MODEL YK STYLE F R 134a COOLING ONLY WITH OPTIVIEWTM CONTROL CENTER FOR ELECTRO MECHANICAL STARTER SOLID STATE STARTER VARIABLE...

Page 2: ...materials This individual shall also be familiar with and comply with all applicable governmental standards and regulations pertaining to the task in question SAFETY SYMBOLS The following symbols are...

Page 3: ...NCLATURE YK CB CB P6 CM F MOTOR 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 5...

Page 4: ...ystem and Fundamentals of Operation 6 SECTION 2 System Operating Procedures 9 SECTION 3 System Components Description 15 SECTION 4 Operational Maintenance 21 SECTION 5 Troubleshooting 23 SECTION 6 Mai...

Page 5: ...M STARTER SOLID STATE STARTER 10 FIG 5 CHILLER STARTING SEQUENCE SHUTDOWN SEQUENCE VARIABLE SPEED DRIVE 11 FIG 6 LIQUID CHILLER LOG SHEETS 12 FIG 7 SYSTEM COMPONENTS 15 FIG 8 SCHEMATIC DRAWING YK COMP...

Page 6: ...n external SECTION 1 DESCRIPTION OF SYSTEM AND FUNDAMENTALS OF OPERATION 00116vip CONDENSER CONTROL CENTER COMPRESSOR MOTOR EVAPORATOR FIG 1 MODEL YK MAXETM CHILLER SYSTEM OPERATION DESCRIPTION SEE FI...

Page 7: ...ity 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...

Page 8: ...FORM 160 73 O2 605 8 FIG 2 REFRIGERANT FLOW THRU CHILLER PREROTATION VANES See Detail A SUCTION EVAPORATOR ELIMINATOR OIL COOLER LD00924 FLOW CONTROL ORIFICE SUB COOLER CONDENSER DISCHARGE BAFFLE DIS...

Page 9: ...operated start the pump The Control Center will not allow the chiller to start unless chilled liquid ow is established through the unit A eld supplied chilled water ow switch is required If the chill...

Page 10: ...rt to circulate oil for a 50 second pre run to establish oil ow and adequate lubrication to all bearings gears and rotating surfaces within the compressor The high and low oil pressure transducers OP...

Page 11: ...current limit software function plus the 3 phase 100 solid state overload current limiter CM 2 on Electro Mechanical Starter applications or the Solid State Starter current Limit function will overrid...

Page 12: ...ing condenser water temperature may be as much as 25 F 14 C colder than the standby return chilled water temperature Cooling tower fan cycling will normally provide adequate control of the entering co...

Page 13: ...erant analysis 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 Table 1 pages 23...

Page 14: ...water from the cooling tower condenser condenser pump and the chilled water system chilled water pump and coils Open the drains on the evaporator and condenser liquid heads to assure complete drainage...

Page 15: ...SECTION 3 SYSTEM COMPONENTS DESCRIPTION MOTOR EVAPORATOR COMPRESSOR SUCTION DUAL RELIEF VALVES SIGHT GLASS VARIABLE SPEED OIL PUMP CONTROL BOX REFRIGERANT CHARGING VALVE 00611vip FRONT VIEW FIG 7 SYS...

Page 16: ...YORK INTERNATIONAL FORM 160 73 O2 605 16 FIG 7 SYSTEM COMPONENTS CONT D 28778A DISCHARGE LINE OIL COOLER OIL RESERVOIR PUMP REAR VIEW System Components Description...

Page 17: ...d all interconnecting oil piping and passages There are main points within the motor compressor which must be supplied with forced lubri cation as follows 1 Compressor Drive Shaft Low Speed a Shaft se...

Page 18: ...YORK INTERNATIONAL FORM 160 73 O2 605 18 LOW SPEED GEAR REAR BEARING DOUBLE BELLOWS SHAFT SEAL FIG 8 SCHEMATIC DRAWING YK COMPRESSOR LUBRICATION SYSTEM LD08577 System Components Description...

Page 19: ...rcurrent transformers are furnished with all units HEAT EXCHANGERS Evaporator and condenser shells are fabricated from rolled carbon steel plates with fusion welded seams Heat exchanger tubes are inte...

Page 20: ...refrigerant Isolation of the refrigerant in this sys tem must be performed by a quali ed service technician OPTIONAL HOT GAS BYPASS Hot gas bypass is optional and is used to eliminate compressor surge...

Page 21: ...ducing the low pressure oil rich liquid to ow from the evaporator through the dehydrator to the compressor sump CHANGING THE DEHYDRATOR To change the dehydrator use the following pro cedure 1 Shut the...

Page 22: ...mp discharge connection to the oil charging valve A located on the remote oil reservoir cover plate See Fig 10 Do not tighten the connection at the charging valve until after the air is forced out by...

Page 23: ...ant into system greater than normal with high discharge Variable ori ce problem Remove obstruction temperature Temperature difference between leaving Evaporator tubes dirty or Clean evaporator tubes c...

Page 24: ...SYMPTOM REDUCED OIL PUMP CAPACITY Oil pump pumping capacity Excessive end clearance Inspect and replace worn parts pump Other worn pump parts Partially blocked oil supply Check oil inlet for blockage...

Page 25: ...ector can be used to detect any leaks too small to be found by the soap test To test with R 22 proceed as follows 1 With no pressure in the system charge R 22 gas into the system through the charging...

Page 26: ...isconnect the vacuum pump leaving the vac uum indicator in place 6 Hold the vacuum obtained in Step 3 in the system for 8 hours the slightest rise in pressure indicates a leak or the presence of moist...

Page 27: ...d found to be tight prior to evacuation then the saturation temperature recordings should follow a curve similar to the typical saturation curve shown as Fig 12 The temperature of the water in the tes...

Page 28: ...iller model See Table 3 Charge the correct amount of refrigerant and record the level in the evaporator sight glass The refrigerant charge should always be checked and trimmed when the system is shut...

Page 29: ...the condenser or evaporator compressor while making any necessary repairs While the main disconnect switch and compressor motor starter are open meg the motor as follows 1 Using a megohm meter megger...

Page 30: ...ERNATIONAL FORM 160 73 O2 605 30 LD00476 FIG 14 MOTOR STARTER TEMPERATURE AND INSULATION RESISTANCES Minimum Insulation Resistance vs Temperature per IEEE Std 43 Open Motors Maintenance TEMPERATURE F...

Page 31: ...ead pressure over a period of time accompanied by a steady rise in condensing temperature and noisy operation These symptoms may also be due to foul gas buildup Purging will remove the foul gas reveal...

Page 32: ...the ends of all tubes with water Do not use carbon tetrachloride for this purpose since its fumes give the same ame discoloration that the refrigerant does 3 With nitrogen or dry air blow out the tub...

Page 33: ...lines passages or dirty oil lters If the unit is shutting down on HOT High Oil Temperature or Low Oil Pressure OP change the oil lter element Examine the oil lter element for the presence of alu minum...

Page 34: ...re not supplied and bearings are designed for long life under standard conditions Frames 284T thru 587UZ are furnished with double shielded or open ball or roller bearings It is necessary to re lubric...

Page 35: ...user to provide for proper water treatment to provide for a longer and more economical life of the equipment The following recommendation should be followed in determining the condition of the water...

Page 36: ...861 1001 www york com P O Box 1592 York Pennsylvania USA 17405 1592 Subject to change without notice Printed in USA Copyright by YORK International Corporation 2005 ALL RIGHTS RESERVED Form 160 73 O2...

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