| Document type | Installation Guide |
|---|---|
| Document number | 150.72-NM1 |
| Equipment | YLAA Scroll Chiller |
| Brand | YORK |
| File size | 37.6 MB |
Fault codes in this document
System Safeties
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| S Y S 1 L O W S U C T P R E S S S Y S 2 L O W S U C T P R E S S | Suction Pressure Cutout — a software cutout that helps protect the chiller from an evaporator freeze-up should the system attempt to run with a low refrigerant charge or a restriction in the refrigerant circuit. | Suction pressure falls below the ramped cutout point. At system start the cutout is set to 10% of the programmed value and ramps up to the programmed cutout point over the next 3 minutes; the cutout is completely ignored for the first 30 seconds of system run time. After the first 3 minutes, if the suction pressure falls below the programmed cutout setting, a "transient protection routine" is activated: the cutout is set at 10% of the programmed value and ramps up over the next 30 seconds; if at any time during this 30 seconds the suction pressure falls below the ramped cutout, the system stops. | System stops. Auto reset fault — the system is allowed to restart automatically after the fault condition is no longer present; however, if 3 faults on the same system occur within 90 minutes, that system is locked out on the last fault (manual reset: the system switch under the OPTIONS key must be turned off and then back on). Manual warning: repeated starts after resetting a low suction pressure fault will cause evaporator freeze-up; whenever a system locks out on this safety or any safety, immediate steps should be taken to identify the cause. | 129 |
| S Y S 1 M P / H P C O F A U L T S Y S 2 M P / H P C O F A U L T | Motor Protector/Mechanical High Pressure Cutout — protects the compressor motor from overheating or the system from experiencing dangerously high discharge pressure. | Fault condition is present when CR1 (SYS 1) or CR2 (SYS 2) relays de-energize due to the HP switch or motor protector opening. The internal motor protector opens at 185°F – 248°F (85°C – 120°C) and auto resets; the mechanical HP switch opens at 585 PSIG plus or minus 10 PSIG (27.92 barg plus or minus .69 barg) and closes at 330 PSIG plus or minus 25 PSIG (22.75 barg plus or minus 1.72 barg). The compressor discharge temperature sensor also opens the motor protector circuit when it senses high internal scroll temperature (overheating due to inadequate cooling that may occur when refrigerant charge is low or superheat is too high). This message is displayed only after 3 shutdowns in 90 minutes, indicating the system is locked out and will not restart. | Whenever the motor protector or discharge sensor shuts down a compressor and the system, the internal compressor contacts open for a period of 30 minutes to assure that the motor or scroll temperatures have time to dissipate the heat and cool down; compressors will not be permitted to start during this period. The fault condition is cleared when a 30 VDC signal is restored to the input. After the third fault in 90 minutes the system is locked out — manual reset: the system switch under the OPTIONS key must be turned off and then back on. | 129 |
| S Y S 1 M P / H P C O I N H I B S Y S 2 M P / H P C O I N H I B | Motor Protector / High Pressure Cutout inhibit — displayed during the 30 minute timeout after a motor protector or discharge sensor shutdown, or when the HPCO is open. | The motor protector or discharge temperature sensor shut down a compressor and the system; the internal compressor contacts open for 30 minutes to assure that the motor or scroll temperatures have time to dissipate the heat and cool down, or the HPCO is open. During the first two faults this message is displayed and the system is not locked out. | While this message is displayed the compressors will not be permitted to start. After 30 minutes the contacts close and the system will be permitted to restart. Only after the third fault in 90 minutes will the MP/HPCO FAULT message be displayed (system locked out). | 129 |
| S Y S 1 H I G H D S C H P R E S S Y S 2 H I G H D S C H P R E S | Discharge Pressure Cutout — a software cutout in the microprocessor, backed up by a mechanical high pressure cutout switch located in the refrigerant circuit; assures that the system pressure does not exceed safe working limits. Discharge transducers must be installed for this function to operate. | Discharge pressure exceeded the programmable cutout. | System shuts down. Auto reset fault — the system will be allowed to restart when the discharge pressure falls 40 PSIG below the cutout. However, if 3 faults on the same system occur within 90 minutes, that system is locked out on the last fault (manual reset: the system switch under the OPTIONS key must be turned off and then back on). | 129 |
| S Y S 1 H I G H M T R C U R R S Y S 2 H I G H M T R C U R R | System high motor current safety — operates when the System Current Feedback option is installed and selected (Option 11 under OPTIONS key, Current Feedback). | The actual feedback voltage of the system, proportional to currents, exceeds the programmed trip voltage for 5 seconds. | System shutdown. Auto reset fault — the system is allowed to restart automatically after the fault condition is no longer present; however, if 3 faults on the same system occur within 90 minutes, that system is locked out on the last fault (manual reset: the system switch under the OPTIONS key must be turned off and then back on). | 130 |
Unit Safeties
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| U N I T F A U L T : L O W A M B I E N T T E M P | Low Ambient Temp Cutout — a safety shutdown designed to protect the chiller from operating in a low ambient condition. Unit faults cause all running compressors to be shut down and are auto reset faults. | The outdoor ambient temperature falls below the programmable cutout. | Chiller shuts down. Auto reset — the unit is allowed to restart automatically after the fault condition is no longer present; restart can occur when temperature rises 2°F above the cutoff. | 131 |
| U N I T F A U L T : L O W L I Q U I D T E M P | Low Leaving Chilled Liquid Temp Cutout — protects the chiller from an evaporator freeze-up should the chilled liquid temperature drop below the freeze point. Unit faults cause all running compressors to be shut down and are auto reset faults. | This situation could occur under low flow conditions or if the micro panel setpoint values are improperly programmed; anytime the leaving chilled liquid temperature (water or glycol) drops below the cutout point. | Chiller shuts down. Auto reset — restart can occur when chilled liquid temperature rises 2°F above the cutout. | 131 |
| U N I T F A U L T : 1 1 5 V A C U N D E R V O L T A G E | Under Voltage Safety — assures that the system is not operated at voltages where malfunction of the microprocessor could result in system damage. Unit faults cause all running compressors to be shut down and are auto reset faults. | The 115V AC to the micro panel drops below a certain level. | A unit fault is initiated to safely shut down the unit. Auto reset — restart is allowed after the unit is fully powered again and the anti-recycle timers have finished counting down. | 131 |
| U N I T F A U L T : H I G H M T R C U R R | Unit high motor current safety — active when the CURRENT FEEDBACK ONE PER UNIT option is selected under the OPTIONS key. Unit faults cause all running compressors to be shut down. | The voltage exceeds the programmed trip voltage for 5 seconds. The trip voltage is programmed at the factory according to compressor or unit RLA. | Unit shuts down. Restart will occur after the anti-recycle timer times out. | 131 |
Unit Warning
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| ! ! L O W B A T T E R Y ! ! C H E C K P R O G / S E T P / O P T N | Low Battery Warning — can only occur at unit power-up; on micro panel power-up the RTC battery is checked. Not a unit safety; not logged to the history buffer; will not auto-restart. | A low battery is found at power-up. All programmed setpoints, program values, options, time, schedule, and history buffers will be lost; these values will all be reset to their default values which may not be the desired operating values. | Once a faulty battery is detected, the unit will be prevented from running until the PROGRAM key is pressed; once PROGRAM is pressed the anti-recycle timers will be set to the programmed anti-recycle time to allow the operator time to check setpoints and, if necessary, reprogram programmable values and options. If a low battery is detected, it should be replaced as soon as possible (RTC/battery 031-02565-000, located at U5 on the microboard); the programmed values will all be lost and the unit will be prevented from running on the next power interruption. Operator intervention is required to allow a restart of the chiller. | 131 |
| I N C O R R E C T U N I T T Y P E | Incorrect Unit Type warning — indicates the condensing unit jumper is installed. Not a unit safety; not logged to the history buffer; will not auto-restart. | Condensing unit jumper installed between J11-12 and J11-7. | This jumper must be removed to operate the chiller. Operator intervention is required to allow a restart of the chiller. | 131 |
Troubleshooting
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| NO DISPLAY ON PANEL. UNIT WILL NOT OPERATE. | 1. No 115VAC to 24 VAC Transformer. 2. No 24VAC to Microboard. 3. Control Transformer defective, no 24VAC output. 4. Short in wire to temp. sensors or pressure transducers. 5. Defective IPU II & I/O Board or the Display Board. | 1a. Check wiring and fuse 1FU. 1b. Check wiring emergency stop contacts 5 to L of XTBC2 Terminal Block. 1c. Replace Control Transformer. 2. Check wiring Control Transformer to Microboard. 3. Replace Control Transformer. 4. Unplug connections at IPU II & I/O Board to isolate. 5. Replace IPU II & I/O Board or the Display Board. Contact Johnson Controls Service before replacing circuit Boards! | 174 | |
| FLOW SWITCH/REM STOP NO RUN PERMISSIVE | 1. No chilled liquid flow. 2. Flow switch improperly installed. 3. Defective flow switch. 4. Remote cycling device open. | 1. Check chilled liquid flow. 2. Check that the flow switch is installed according to manufacturer's instructions. 3. Replace flow switch. 4. Check cycling devices connected to terminals 13 and 14 of the XTBC1 Terminal Block. | 174 | |
| LOW SUCTION PRESSURE FAULT | 1. Improper suction pressure cutouts adjustments. 2. Low refrigerant charge. 3. Fouled filter dryer. 4. TXV defective. 5. Reduced flow of chilled liquid through the cooler. 6. Defective suction pressure transducer/low pressure switch or wiring. 7. LLSV defective | 1. Adjust per recommended settings. 2. Repair leak if necessary and add refrigerant. 3. Change dryer/core. 4. Replace TXV. 5. Check GPM (See "Limitations" liquid through the cooler in Installation section). Check operation of pump, clean pump strainer, purge chilled liquid system of air. 6. Replace transducer/low pressure switch or faulty switch or wiring. Refer to "Service" section for pressure/voltage formula. 7. Replace LLSV | 174 | |
| HIGH DISCHARGE PRESSURE FAULT | 1. Condenser fans not operating or operating backwards. 2. Too much refrigerant. 3. Air in refrigerant system. 4. Defective discharge pressure transducer. | 1. Check fan motor, and contactors. Assure fan blows air upward. 2. Remove refrigerant. 3. Evacuate and recharge system. 4. Replace discharge pressure transducer. Refer to Service section for pressure/voltage formula. | 174 | |
| LOW LIQUID TEMP FAULT | 1. Improperly adjusted leaving chilled liquid temp. cutout (glycol only). 2. Micro panel setpoint/range values improperly programmed. 3. Chilled liquid flow too low. 4. Defective LWT or RWT sensor (assure the sensor is properly installed in the bottom of the well with a generous amount of heat conductive compound). | 1. Re-program the leaving chilled liquid temp. cutout. 2. Re-adjust setpoint/range. 3. Increase chilled liquid flow. Refer to Limitations in Installation section. 4. Compare sensor against a known good Temperature sensing device. Refer to Service section for temp./voltage table. | 175 | |
| MP / HPCO FAULT | 1. Compressor internal motor protector (MP) open. 2. External overload tripped. 3. HPCO switch open. 4. Defective HPCO switch. 5. Defective CR relay. | 1. Verify refrigerant charge is not low. Verify superheat setting of 10°F to 15°F (5.6°C to 8.3°C). Verify correct compressor rotation. Verify compressor is not overloaded. 2. Determine cause and reset. 3. See "High Press. Disch." Fault. 4. Replace HPCO switch. 5. Replace relay. | 175 | |
| COMPRESSOR(S) WON'T START | 1. Demand not great enough. 2. Defective water temperature sensor. 3. Contactor/Overload failure. 4. Compressor failure. | 1. No problem. Consult "Installation" Manual to aid in understanding compressor operation and capacity control. 2. Compare the display with a thermometer. Should be within +/- 2 degrees. Refer to Service section for RWT/LWT temp./voltage table. 3. Replace defective part. 4. Diagnose cause of failure and replace. | 175 | |
| LACK OF COOLING EFFECT | 1. Fouled evaporator surface. Low suction pressure will be observed. 2. Improper flow through the evaporator. 3. Low refrigerant charge. Low suction pressure will be observed. | 1. Contact the local Johnson Controls service representative. 2. Reduce flow to within chiller design specs. See Limitations in Installation section. 3. Check subcooling and add charge as needed. | 175 |
Real Time Error Numbers
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| ## 1 | DATUM TYPE OK TEST FAILED | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 2 | ENGLISH TEXT TOO LONG | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 3 | FLOATING POINT EXCEPTION | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 4 | GET PACKET FAILED | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 5 | GET TYPE FAILED | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 6 | INVALID UNIT CONVERSION | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 7 | INVALID HARDWARE SELECTION | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 8 | REAL TIME FAULT | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 9 | SPANISH TEXT TOO LONG | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 10 | THREAD EXITED | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 11 | THREAD FAILED | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 12 | THREAD STALLED | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 13 | IO BOARD RESET | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 14 | BRAM INVALID | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 | |
| ## 15 | BACNET SETUP FAILED | Reset via the "RESET REAL TIME ERROR" setting (set RESET 1 = YES, 0 = NO). Reboot (cycle power) required after settings are changed. | 184 |
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