| Document type | Installation Guide |
|---|---|
| Document number | 150.72-NM2 |
| Equipment | YLAA Scroll Chiller |
| Brand | YORK |
| File size | 37.8 MB |
Fault codes in this document
System Safeties
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| 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. Software cutout in the microprocessor, backed up by a mechanical high pressure cutout switch located in the refrigerant circuit; assures the system pressure does not exceed safe working limits. | Programmable discharge pressure cutout exceeded. Troubleshooting causes: condenser fans not operating or operating backwards; too much refrigerant; air in refrigerant system; defective discharge pressure transducer. | System shuts down when the programmable cutout is exceeded; restart is allowed when the discharge pressure falls 40 PSIG below the cutout. Discharge transducers must be installed for this function to operate. Auto reset: the system restarts 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 — turn the system switch under the OPTIONS key OFF and then back ON to clear). Solutions: check fan motor and contactors, assure fan blows air upward; remove refrigerant; evacuate and recharge system; replace discharge pressure transducer. | 127 |
| 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. 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 fell below the programmed cutout. Troubleshooting causes: improper suction pressure cutout adjustments; low refrigerant charge; fouled filter dryer; TXV defective; reduced flow of chilled liquid through the cooler; defective suction pressure transducer / low pressure switch or wiring; LLSV defective. | At system start the cutout is set to 10% of the programmed value and ramped up to the programmed cutout point during the next 3 minutes (completely ignored for the first 30 seconds of system run time); the system stops if suction pressure falls below the ramped cutout. After the first 3 minutes, a “transient protection routine” sets the cutout at 10% of the programmed value and ramps it up over the next 30 seconds; the system stops if suction pressure falls below the ramped cutout. 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. Auto reset; if 3 faults on the same system occur within 90 minutes the system locks out on the last fault (clear by turning the system switch under OPTIONS OFF, then back ON). Solutions: adjust per recommended settings; repair leak if necessary and add refrigerant; change dryer/core; replace TXV; check GPM, check operation of pump, clean pump strainer, purge chilled liquid system of air; replace transducer/low pressure switch or faulty wiring; replace LLSV. | 127 |
| 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 fault. Protects the compressor motor from overheating or the system from experiencing dangerously high discharge pressure. Displayed only after the third shutdown in 90 minutes — the system is locked out and will not restart. | CR1 (SYS 1) or CR2 (SYS 2) relays de-energize due to the HP switch or motor protector opening, causing 0VDC to be read on the inputs to the microboard. The internal motor protector opens at 185 °F to 248 °F (85 °C to 120 °C) and auto resets; the mechanical HP switch opens at 585 PSIG plus or minus 10 PSIG and closes at 330 PSIG plus or minus 25 PSIG. The compressor discharge temperature sensor also opens the motor protector circuit when it senses high internal scroll temperature (inadequate cooling — refrigerant charge low, or superheat too high). Troubleshooting causes: compressor internal motor protector (MP) open; external overload tripped; HPCO switch open; defective HPCO switch; defective CR relay. | Fault condition is cleared when a 30VDC signal is restored to the input. During the first two faults an MP/HP INHIBIT message is displayed and the system is not locked out; only after the third fault in 90 minutes is the MP/HPCO FAULT message displayed, indicating the system is locked out and will not restart. Internal compressor contacts open for 30 minutes so motor or scroll temperatures can dissipate heat; after 30 minutes the contacts close and the system is permitted to restart. Solutions: verify refrigerant charge is not low; verify superheat setting of 10 °F to 15 °F; verify correct compressor rotation; verify compressor is not overloaded; determine cause and reset external overload; see High Press. Disch. Fault; replace HPCO switch; replace relay. | 127 |
| 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 while the internal compressor contacts are open or when the HPCO is open; the compressors will not be permitted to start. | The motor protector or discharge temperature sensor shut down a compressor and the system; the internal compressor contacts open for a period of 30 minutes to assure the motor or scroll temperatures have time to dissipate the heat and cool down. Also displayed when the HPCO is open. | While this message is displayed the compressors will not be permitted to start. After 30 minutes the contacts close and the system is permitted to restart. During the first two faults this message is displayed and the system is not locked out; only after the third fault in 90 minutes is the MP/HPCO FAULT message displayed (lockout). | 127 |
| 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). | The actual feedback voltage of the system, proportional to currents, exceeds the programmed trip voltage for 5 seconds; or the suction temperature or suction pressure sensors read out of range high or low (condition present for 3 seconds). | System shutdown. This safety locks out a system after the first fault and will not allow automatic restarting. | 128 |
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. Safety shutdown designed to protect the chiller from operating in a low ambient condition. Causes all running compressors to be shut down. | Outdoor ambient temperature fell below the programmable cutout. | Chiller shuts down. Auto reset: restart can occur when temperature rises 2 °F above the cutoff. | 128 |
| 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. Causes all running compressors to be shut down. | Leaving chilled liquid temperature (water or glycol) dropped below the cutout point — could occur under low flow conditions or if the micro panel setpoint values are improperly programmed. Troubleshooting causes: improperly adjusted leaving chilled liquid temp. cutout (glycol only); micro panel setpoint/range values improperly programmed; chilled liquid flow too low; defective LWT or RWT sensor. | Chiller shuts down. Auto reset: restart can occur when chilled liquid temperature rises 2 °F above the cutout. Solutions: re-program the leaving chilled liquid temp. cutout; re-adjust setpoint/range; increase chilled liquid flow; compare sensor against a known good temperature sensing device. | 128 |
| 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. Causes all running compressors to be shut down. | 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. | 128 |
| 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). Causes all running compressors to be shut down. | 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. Auto reset: restart will occur after the anti-recycle timer times out. | 128 |
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. Not a unit safety; not logged to the history buffer. Can only occur at unit power-up. | On micro panel power-up the RTC battery is checked and a low battery is found. All programmed setpoints, program values, options, time, schedule, and history buffers are lost and reset to their default values, which may not be the desired operating values. | Will not auto-restart — operator intervention is required to allow a restart of the chiller. The unit is prevented from running until the PROGRAM key is pressed; once PROGRAM is pressed, the anti-recycle timers are set to the programmed anti-recycle time to allow the operator time to check setpoints and, if necessary, reprogram programmable values and options. Replace the battery as soon as possible — RTC/battery (031-02565-000) is 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. | 129 |
| I N C O R R E C T U N I T T Y P E | Incorrect unit type warning. Not a unit safety; not logged to the history buffer. | The condensing unit jumper is installed between J11-12 and J11-7. | Will not auto-restart — operator intervention is required to allow a restart of the chiller. This jumper must be removed to operate the chiller. | 129 |
Option 17 – Flash Card Update
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| F L A S H C A R D U P D A T E E R R O R XXXXX | Flash Card operating-software update ended in an error; XXXXX is the error code. No reboot occurs. | Incorrect Flash Card utilized; incorrect chiller software; the Flash Card is most likely defective; or the IPU and I/O combo board is bad. | If the update resulted in an error, the original program will still be active. Assure the correct Flash Card was utilized — incorrect chiller software will cause an error; if this is not the case, the Flash Card is most likely defective or the IPU and I/O combo board is bad. | 150 |
Real Time Error Numbers
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| REAL TIME ERROR 1 | DATUM TYPE OK TEST FAILED | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 2 | ENGLISH TEXT TOO LONG | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 3 | FLOATING POINT EXCEPTION | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 4 | GET PACKET FAILED | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 5 | GET TYPE FAILED | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 6 | INVALID UNIT CONVERSION | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 7 | INVALID HARDWARE SELECTION | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 8 | REAL TIME FAULT | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 9 | SPANISH TEXT TOO LONG | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 10 | THREAD EXITED | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 11 | THREAD FAILED | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 12 | THREAD STALLED | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 13 | IO BOARD RESET | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 14 | BRAM INVALID | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 | |
| REAL TIME ERROR 15 | BACNET SETUP FAILED | Reset via the RESET REAL TIME ERROR setting (1 = YES, 0 = NO). | 182 |
Every row above cites the page of this document it came from, and each one is re-read against that page by an automatic check before publication.
Manufacturer document, published here as reference material for equipment we supply. The original lives at docs.johnsoncontrols.com. The rights holder may ask us to take it down — we will.