| Document type | Service Information Letter |
|---|---|
| Document number | SI0630 |
| Equipment | YVAA Style A |
| Brand | YORK |
| Revised | 2026-03-20 |
| File size | 0.9 MB |
Fault codes in this document
Errors (IPU3 Software Update)
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| MORE THAN ONE FILE FOUND PRESS TO CONTINUE (x) | Error message displayed during IPU3 program update. | More than one *.bin file is on the selected device. | Displayed until the user presses the Enter key and returns to the software download display. | 5 |
| FILE NOT FOUND PRESS TO CONTINUE (x) | Error message displayed during IPU3 program update. | No *.bin file is on the selected device. | Displayed until the user presses the Enter key and returns to the software download display. | 5 |
| FILE NOT ABLE TO BE LOADED PRESS TO CONTINUE (x) | Error message displayed during IPU3 program update. | The *.bin file cannot be loaded to SPI flash, for example if the embedded checksum verification fails. | Displayed until the user presses the Enter key and returns to the software download display. | 5 |
| SELECTED DEVICE NOT FOUND PRESS TO CONTINUE (x) | Error message displayed during IPU3 program update. | The software update was attempted without a SD or USB device inserted. | Displayed until the user presses the Enter key and returns to the software download display. | 5 |
| FLASH ERROR XX PRESS TO CONTINUE (x) | Displayed if other internal errors occur during the software update. The Error Code displayed in the XX field is one of: 90 — FILE_BUFFER_APP_HEADER_READ 91 — CANNOT_CALCULATE_BUFFER_DATA_CRC 92 — BAD_FILE_BUFFER_DATA_CRC 93 — SFLASH_DEVICE_WRITE 94 — BAD_SFLASH_CRC 95 — APP_CODE_TOO_BIG 96 — SPI_FLASH_APP_NOT_PRESENT 97 — SPI_FLASH_READ_ERROR 98 — CANNOT_READ_DEVICE_CONFIGURATION | Other internal errors occurred during the software update. | Displayed until the user presses the Enter key. | 5 |
Unit Faults
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| 1 Low Ambient Temperature | Unit fault — Panel source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. | 16 | |
| 2 High Ambient Temperature | Unit fault — Panel source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. | 16 | |
| 3 Low Chilled Liquid Temperature | Unit fault — Panel source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. | 16 | |
| 4 VSD Initialization Failure | Unit fault — Panel source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. | 16 | |
| 5 Low RTC Battery Voltage | Unit fault — Panel source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. | 16 | |
| 6 Invalid Number of Compressors Selected | Unit fault — Panel source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. | 16 | |
| 7 VSD Communications Failure | Unit fault — Panel source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. | 16 | |
| 8 Pre-charge Low DC Bus Voltage | Unit fault — VSD source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. If any 3 (or more) VSD-related unit faults occur within 90 minutes, the unit triggers a lockout on the last fault in the range. A lockout requires manual reset, done via the System Switches button on the keypad or HMI. | 16 | |
| 9 Pre-charge DC Bus Voltage Imbalance | Unit fault — VSD source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. If any 3 (or more) VSD-related unit faults occur within 90 minutes, the unit triggers a lockout on the last fault in the range. A lockout requires manual reset, done via the System Switches button on the keypad or HMI. | 16 | |
| 10 High DC Bus Voltage | Unit fault — VSD source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. If any 3 (or more) VSD-related unit faults occur within 90 minutes, the unit triggers a lockout on the last fault in the range. A lockout requires manual reset, done via the System Switches button on the keypad or HMI. | 16 | |
| 11 Low DC Bus Voltage | Unit fault — VSD source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. If any 3 (or more) VSD-related unit faults occur within 90 minutes, the unit triggers a lockout on the last fault in the range. A lockout requires manual reset, done via the System Switches button on the keypad or HMI. | 16 | |
| 12 DC Bus Voltage Imbalance | Unit fault — VSD source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. If any 3 (or more) VSD-related unit faults occur within 90 minutes, the unit triggers a lockout on the last fault in the range. A lockout requires manual reset, done via the System Switches button on the keypad or HMI. | 16 | |
| 13 High VSD Ambient Temperature | Unit fault — VSD source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. If any 3 (or more) VSD-related unit faults occur within 90 minutes, the unit triggers a lockout on the last fault in the range. A lockout requires manual reset, done via the System Switches button on the keypad or HMI. | 16 | |
| 14 Single Phase Input | Unit fault — VSD source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. If any 3 (or more) VSD-related unit faults occur within 90 minutes, the unit triggers a lockout on the last fault in the range. A lockout requires manual reset, done via the System Switches button on the keypad or HMI. | 16 | |
| 15 VSD Power Supply Fault | Unit fault — VSD source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. If any 3 (or more) VSD-related unit faults occur within 90 minutes, the unit triggers a lockout on the last fault in the range. A lockout requires manual reset, done via the System Switches button on the keypad or HMI. | 16 | |
| 16 VSD Logic Board Fault | Unit fault — VSD source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. If any 3 (or more) VSD-related unit faults occur within 90 minutes, the unit triggers a lockout on the last fault in the range. A lockout requires manual reset, done via the System Switches button on the keypad or HMI. | 16 | |
| 17 Motor Current Overload (Hardware) | Unit fault — VSD source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. If any 3 (or more) VSD-related unit faults occur within 90 minutes, the unit triggers a lockout on the last fault in the range. A lockout requires manual reset, done via the System Switches button on the keypad or HMI. | 16 | |
| 18 CT Plug Fault | Unit fault — VSD source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. If any 3 (or more) VSD-related unit faults occur within 90 minutes, the unit triggers a lockout on the last fault in the range. A lockout requires manual reset, done via the System Switches button on the keypad or HMI. | 16 | |
| 19 High Harmonic Filter Temperature | Unit fault — Panel source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. | 16 | |
| 20 Evap Anti-Freeze Pump Fault | Unit fault — Panel source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. | 16 | |
| 21 SPARE | Unit fault — Panel source | 16 | ||
| 22 Replace RTC Battery | Unit fault — Panel source | If unit faults exceed a set threshold for 3 seconds, all running compressors are shut down. Unit faults are logged in the history buffer. Most unit faults are auto-reset; the unit can restart automatically after the fault condition is cleared. | 16 | |
| 23 SPARE | Unit fault — source not listed | 16 | ||
| 24 SPARE | Unit fault — source not listed | 16 | ||
| 25 SPARE | Unit fault — source not listed | 16 | ||
| 26 SPARE | Unit fault — source not listed | 16 |
System Faults
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| 27 High Discharge Pressure (Software) | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 16 | |
| 28 High Differential Oil Pressure | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 16 | |
| 29 Low Differential Oil Pressure | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 16 | |
| 30 Low Suction Pressure | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 16 | |
| 31 High Discharge Temperature | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 16 | |
| 32 SPARE | System fault — Panel source | 17 | ||
| 33 Eductor Clog Fault | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 34 Sensor Failure | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 35 Low Motor Current | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 36 High Motor Temperature | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 37 Pre-charge Low DC Bus Voltage | System fault — VSD source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 38 Pre-charge DC Bus Voltage Imbalance | System fault — VSD source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 39 High DC Bus Voltage | System fault — VSD source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 40 Low DC Bus Voltage | System fault — VSD source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 41 DC Bus Voltage Imbalance | System fault — VSD source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 42 High Motor Current | System fault — VSD source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 43 Motor Current Overload (Software) | System fault — VSD source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 44 IGBT Gate Driver Fault | System fault — VSD source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 45 High Baseplate Temperature | System fault — VSD source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 46 Single Phase Input | System fault — VSD source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 47 VSD Run Signal Fault | System fault — VSD source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 48 High Discharge Press (Hardware – HPCO) | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 49 Spare | System fault — Panel source | 17 | ||
| 50 Control Voltage Fault | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 51 Low Discharge Superheat | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 52 Low Suction Pressure Smart Freeze | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 53 Isolation Valve Failed to Close Warning | System fault — Panel source | 17 | ||
| 54 Isolation Valve Failed to Open Fault | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 55 High Discharge Pressure Rate | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 56 Condenser Fan VSD Warning | System fault — Panel source | 17 | ||
| 57 Low Economizer Superheat | System fault — Panel source | If a system fault threshold is exceeded for 3 seconds, only the affected system is shut down (not the whole unit/all systems). System faults are auto-reset; the system restarts automatically after the fault condition clears. If 3 faults on the same system occur within 90 minutes, that system is locked out after the third fault. Lockout requires manual reset: the operator must cycle the system switch off then on to clear the lockout. | 17 | |
| 58 SPARE | System fault — source not listed | 17 | ||
| 59 SPARE | System fault — source not listed | 17 | ||
| 60 SPARE | System fault — source not listed | 17 | ||
| 61 SPARE | System fault — source not listed | 17 | ||
| 62 SPARE | System fault — source not listed | 17 |
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.