| Document type | Installation Guide |
|---|---|
| Document number | 150.72-ICOM7 |
| Equipment | YLAA Scroll Chiller |
| Brand | YORK |
| File size | 11.3 MB |
Fault codes in this document
System Safeties
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| SYS 1 HIGH DSCH PRES SYS 2 HIGH DSCH PRES | The Discharge Pressure Cutout is a software cutout in the microprocessor and is backed-up by a mechanical high pressure cutout switch located in the refrigerant circuit. It ensures that the system pressure does not exceed safe working limits. | System safeties shut the individual system down if a safety threshold is exceeded for 3 seconds. The system shuts down when the programmable cutout is exceeded and is allowed to restart 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; if 3 faults on the same system occur within 90 minutes, the system locks out on the last fault — a manual reset: turn the system switch (under OPTIONS key) OFF and then back ON to clear the lockout fault. | 118 | |
| SYS 1 LOW SUCT PRESS SYS 2 LOW SUCT PRESS | The Suction Pressure Cutout is 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. | Low refrigerant charge or a restriction in the refrigerant circuit. | At system start the cutout is set to 10% of the programmed value and ramped up to the programmed cutout point over the next 3 minutes; the cutout is completely ignored for the first 30 s of system run time. After the first 3 min, if the suction pressure falls below the programmed cutout setting, a transient protection routine sets the cutout at 10% of the programmed value and ramps it up over the next 30 s; the system stops if the suction pressure falls below the ramped cutout. WARNING: repeated starts after resetting a low suction pressure fault will cause evaporator freeze-up — whenever a system locks out on this safety, immediate steps should be taken to identify the cause. Auto reset with lockout on the third fault in 90 minutes; clear the lockout by turning the system switch (under OPTIONS key) OFF and then back ON. | 169 |
| SYS 1 MP/HPCO FAULT SYS 2 MP/HPCO FAULT | Motor Protector/Mechanical High Pressure Cutout — protects the compressor motor from overheating or the system from experiencing dangerously high discharge pressure. The fault condition is present when CR1 (SYS 1) or CR2 (SYS 2) relays de-energize due to the HP switch or motor protector opening, causing 0 VDC to be read on the inputs to the microboard; the fault condition is cleared when a 30 VDC signal is restored to the input. 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 (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). | Inadequate cooling of the scrolls — refrigerant charge low, or superheat too high (compressor discharge temperature sensor); compressor motor overheating; dangerously high discharge pressure. | 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 min is the MP/HPCO FAULT message displayed, 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 min so the motor or scroll temperatures can dissipate heat and cool down; after 30 min the contacts close and the system is permitted to restart. Clear a lockout by turning the system switch OFF and then back ON (under OPTIONS key). | 168 |
| SYS 1 MP/HPCO INHIB SYS 2 MP/HPCO INHIB | Motor Protector/High Pressure Inhibit — displayed while the internal compressor contacts are open (30-minute timeout) or when the HPCO is open, after the motor protector or discharge temperature sensor has shut down a compressor and the system. | While this message is displayed, the compressors will not be permitted to start. After 30 min, the contacts will close and the system will be permitted to restart. | 168 | |
| SYS 1 HIGH MTR CURR SYS 2 HIGH MTR CURR | With the System Current Feedback option installed and selected (Current Feedback option under the OPTIONS key): if the actual feedback voltage of the system, proportional to currents, exceeds the programmed trip voltage for 5 seconds, the system will shut down. | Auto reset: the system restarts automatically after the fault condition is no longer present; if 3 faults on the same system occur within 90 minutes, the system locks out on the last fault — turn the system switch OFF and then back ON to clear the lockout fault. | 118 | |
| Sensor Failure (EEV) | This safety shuts down a system if either suction temperature or suction pressure sensors read out of range high or low. The condition must be present for 3 s to cause a system shutdown. | Suction temperature or suction pressure sensor reading out of range high or low. | The safety locks out a system after the first fault and will not allow automatic restarting (1X — locks out on the first fault). | 112 |
Unit Safeties
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| UNIT FAULT: LOW AMBIENT TEMP | The Low Ambient Temp Cutout is a safety shutdown designed to protect the chiller from operating in a low ambient condition. Unit safeties are faults that cause all running compressors to be shut down. | Outdoor ambient temperature falls below the programmable cutout. | The chiller shuts down. Restart can occur when temperature rises 2°F above the cutoff. Unit faults are auto reset faults: the unit is allowed to restart automatically after the fault condition is no longer present. | 112 |
| UNIT FAULT: LOW LIQUID TEMP | The 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 safeties are faults that cause all running compressors to be shut down. | Could occur under low flow conditions or if the micro panel set point values are improperly programmed. | Anytime the leaving chilled liquid temperature (water or glycol) drops below the cutout point, the chiller shuts down. Restart can occur when chilled liquid temperature rises 2°F above the cutout. Auto reset. | 112 |
| UNIT FAULT: 115VAC UNDERVOLTAGE | The Under Voltage Safety ensures that the system is not operated at voltages where malfunction of the microprocessor could result in system damage. | 115 V AC to the micro panel drops below a certain level. | A unit fault is initiated to safely shut down the unit. Restart is allowed after the unit is fully powered again and the anti-recycle timers have finished counting down. Auto reset. | 110 |
| UNIT FAULT: HIGH MTR CURR | With the CURRENT FEEDBACK ONE PER UNIT option selected under the OPTIONS key, the unit shuts down when the voltage exceeds the programmed trip voltage for 5 seconds. The trip voltage is programmed at the factory according to compressor or unit RLA. | Current feedback voltage exceeds the programmed trip voltage for 5 seconds. | Restart will occur after the anti-recycle timer times out. Auto reset. | 112 |
| FLOW SWITCH OPEN | Indicates the flow switch contacts connected to Terminals 13 and 14 of XTBC1 are open. | A 3-second delay is built into software to prevent nuisance shutdowns due to erroneous signals from the flow switch. Listed as Unit Fault code 31 (auto reset) in the YLAA Fault and Inhibit Codes. | 107 |
Unit Warning
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| !! LOW BATTERY !! CHECK PROG/SETP/OPTN | Unit warning — not a unit safety, not logged to the history buffer, and will not auto-restart; operator intervention is required to allow a restart. Can only occur at unit power-up: on micro panel power-up the RTC battery is checked, and if a low battery is found, all programmed set points, program values, options, time, schedule, and history buffers are lost and reset to their default values, which may not be the desired operating values. | Faulty RTC battery detected at power-up. | The unit is prevented from running until the PROGRAM key is pressed; pressing PROGRAM sets the anti-recycle timers to the programmed anti-recycle time to allow the operator time to check set points and, if necessary, reprogram programmable values and options. Replace the battery as soon as possible — RTC/battery (031-02565-000), located at U5 on the microboard; the unit will be prevented from running on the next power interruption. | 113 |
| INCORRECT UNIT TYPE | Unit warning — not a unit safety, not logged to the history buffer, and will not auto-restart; operator intervention is required to allow a restart. Indicates the condensing unit jumper is installed between J11-12 and J11-7. | Condensing unit jumper installed between J11-12 and J11-7. | The jumper must be removed to operate the chiller. | 113 |
YLAA Fault and Inhibit Codes
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| 2 | Unit Fault — Low Ambient Temperature | AUTO — allows restart once meeting the required conditions | 112 | |
| 4 | Unit Fault — Low Leaving Chilled Liquid Temperature | AUTO — allows restart once meeting the required conditions | 112 | |
| 22 | Unit Fault — Unit High Motor Current (Unit Current Feedback Option) | AUTO — allows restart once meeting the required conditions | 112 | |
| 27 | Unit Fault — Pump Trip (Hydro Pumps 1 or Hydro Pumps 2) | AUTO — allows restart once meeting the required conditions | 112 | |
| 28 | Unit Fault — Pump Flow Failure (Hydro Pumps 1 or Hydro Pumps 2) | 1X — locks out on the first fault | 112 | |
| 29 | Unit Fault — High Ambient Temperature | AUTO — allows restart once meeting the required conditions | 112 | |
| 31 | Unit Fault — Flow Switch Open | AUTO — allows restart once meeting the required conditions | 112 | |
| 5 | System Fault — High Discharge Pressure (Software) | 3X — automatically restarts on the first and second fault with a lockout on the third fault in 90 minutes | 112 | |
| 7 | System Fault — Low Suction Pressure | 3X — automatically restarts on the first and second fault with a lockout on the third fault in 90 minutes | 112 | |
| 17 | System Fault — System High Motor Current (System Current Feedback option) | 3X — automatically restarts on the first and second fault with a lockout on the third fault in 90 minutes | 112 | |
| 18 | System Fault — Motor Protector/High Pressure (Mechanical) | 3X — automatically restarts on the first and second fault with a lockout on the third fault in 90 minutes | 112 | |
| 19 | System Fault — Low Evaporator Temperature (R407c Only - N/A Hp Heating Mode) | 3X — automatically restarts on the first and second fault with a lockout on the third fault in 90 minutes | 112 | |
| 23 | System Fault — Low Suction Superheat (EEV) | 3X — automatically restarts on the first and second fault with a lockout on the third fault in 90 minutes | 112 | |
| 24 | System Fault — Sensor Failure (EEV) | 1X — locks out on the first fault | 112 | |
| 25 | System Fault — Discharge Inhibit (Heat Pump heating mode only) | 3X — automatically restarts on the first and second fault with a lockout on the third fault in 90 minutes | 112 | |
| 26 | System Inhibit — Motor Protector/High Pressure Inhibit | AUTO — allows restart once meeting the required conditions | 112 |
Fault/Inhibit Code Names (Native BACnet, Modbus, and N2 Communications Data Map)
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| Lockout | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| Unit Fault Low Leaving Chilled Liquid Temperature | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| High Discharge Pressure | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| Low Ambient Temperature | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| System Fault | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| Low Suction Pressure | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| Unit Motor Current | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| Low Superheat | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| Sensor Fault | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| Discharge Inhibit | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| MP/HPCO Inhibit | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| MP/HPCO Fault | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| Leaving Chilled Liquid Temperature Sensor Fault | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| Flow Switch Open | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| Pump Trip | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| Pump Fail Make Flow | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| High Ambient Temperature | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| Anti-Vacuum Low Pressure Cutout | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 | ||
| Low Evaporator Temperature | Fault/inhibit code name in the Native BACnet, Modbus, and N2 communications data map (reported via the Sys 1 / Sys 2 Fault Code points). | 147 |
Troubleshooting
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| NO DISPLAY ON PANEL. UNIT WILL NOT OPERATE | 1. No 115 VAC to 24 VAC Transformer. 2. No 24 VAC to Microboard. 3. Control Transformer defective, no 24 VAC 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! | 179 | |
| 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. | 179 | |
| 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 Operational Limitations on page 45). Check operation of pump, clean pump strainer, purge chilled liquid system of air. 6. Replace transducer/low pressure switch or faulty switch or wiring. See SECTION 9 – SERVICE AND TROUBLESHOOTING for pressure/voltage formula. 7. Replace LLSV | 179 | |
| 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. Ensure fan blows air upward. 2. Remove refrigerant. 3. Evacuate and recharge system. 4. Replace discharge pressure transducer. See SECTION 9 – SERVICE AND TROUBLESHOOTING for pressure/voltage formula. | 179 | |
| LOW LIQUID TEMP FAULT | 1. Improperly adjusted leaving chilled liquid temp. cutout (glycol only). 2. Micro panel set point/range values improperly programmed. 3. Chilled liquid flow too low. 4. Defective LWT or RWT sensor (ensure 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 set point/range. 3. Increase chilled liquid flow. See Operational Limitations on page 45). 4. Compare sensor against a known good Temperature sensing device. See Table 35 on page 172. | 180 | |
| 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. | 180 | |
| COMPRESSORS 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 plus or minus 2 degrees. See Table 35 on page 172 for RWT/LWT temp./voltage table. 3. Replace defective part. 4. Diagnose cause of failure and replace. | 180 | |
| 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 Operational Limitations on page 45). 3. Check subcooling and add charge as needed. | 180 |
Real Time Error Numbers
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| 1 | DATUM TYPE OK TEST FAILED | 143 | ||
| 2 | ENGLISH TEXT TOO LONG | 143 | ||
| 3 | FLOATING POINT EXCEPTION | 143 | ||
| 4 | GET PACKET FAILED | 143 | ||
| 5 | GET TYPE FAILED | 143 | ||
| 6 | INVALID UNIT CONVERSION | 143 | ||
| 7 | INVALID HARDWARE SELECTION | 143 | ||
| 8 | REAL TIME FAULT | 143 | ||
| 9 | SPANISH TEXT TOO LONG | 143 | ||
| 10 | THREAD EXITED | 143 | ||
| 11 | THREAD FAILED | 143 | ||
| 12 | THREAD STALLED | 143 | ||
| 13 | IO BOARD RESET | 143 | ||
| 14 | BRAM INVALID | 143 | ||
| 15 | BACNET SETUP FAILED | 143 |
Flash Card Update Error
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| FLASH CARD UPDATE ERROR XXXXX | Displayed, with the error code, if an error occurred during a Flash Card software update; no reboot will occur and the original program will still be active. | Incorrect chiller software (wrong Flash Card used); if this is not the case, the Flash Card is most likely defective or the IPU and I/O combo board is bad. | Ensure the correct Flash Card was used — incorrect chiller software will cause an error; if the correct card was used, the Flash Card is most likely defective or the IPU and I/O combo board is bad. | 136 |
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