| Document type | Installation Guide |
|---|---|
| Document number | 201.21-NM2 |
| Equipment | YCAV Variable Speed Drive Screw Chiller |
| Brand | YORK |
| Revised | 2023-12-20 |
| File size | 8.6 MB |
Fault codes in this document
VSD SAFETIES (FAULTS)
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| UNIT YYYYYYYY PRECHARGE - LOW DC BUS VOLTAGE SYS X YYYYYYYY PRECHARGE - LOW DC BUS VOLT | DC bus voltage failed to reach minimum levels during pre-charge interval | DC bus voltage did not reach at least 50 VDC within four seconds and 500 VDC within 19 seconds after the pre-charge signal was asserted | Auto-restart safety. Locks out on 3rd fault in 90 minutes. Lockout requires manual reset using keypad. | 173 |
| UNIT YYYYYYYY PRECHARGE - DC BUS VOLTAGE IMBALANCE SYS X YYYYYYYY PRECHARGE-BUS VOLT IMBAL | Half-bus voltage deviated beyond tolerance during pre-charge interval | The 1/2 DC bus voltage magnitude exceeded +/- 100 VDC of the total DC bus voltage divided by two during the pre-charge interval | Locks out on 1st fault. Will not restart until operator clears the fault using the keypad. | 173 |
| UNIT YYYYYYYY HIGH DC BUS VOLTAGE SYS X YYYYYYYY HIGH DC BUS VOLTAGE | DC bus voltage exceeded hardware trip level | DC bus exceeded 766 +/- 30 VDC hardware trip level on the VSD Logic Board | Immediate shutdown. Auto-restart safety. Locks out on 3rd fault in 90 minutes. | 173 |
| UNIT YYYYYYYY LOW DC BUS VOLTAGE SYS X YYYYYYYY LOW DC BUS VOLTAGE | DC bus voltage dropped below software trip level | DC bus dropped below 500 VDC | Immediate shutdown. Auto-restart safety. Locks out on 3rd fault in 90 minutes. | 174 |
| UNIT YYYYYYYY DC BUS VOLTAGE IMBALANCE SYS X YYYYYYYY DC BUS VOLTAGE IMBALANCE | Half-bus voltage deviated beyond tolerance during operation | The 1/2 DC bus magnitude exceeded the +/- 100 VDC tolerances of the total DC bus voltage divided by two | Immediate shutdown. Locks out on 1st fault. Will not restart until operator clears the fault using the keypad. | 174 |
| SYS X YYYYYYYY HIGH MOTOR CURRENT | Instantaneous peak motor current exceeded hardware limit | Nominal peak current trip level is 575.5 Amps (554A min., 597A max.). 380V AC, 60Hz and 400V AC, 50Hz nominal peak current trip level is 649.5 Amps (626 Amps min., 674 Amps max.) | Immediate shutdown. Auto-restart safety. Locks out system on 3rd fault in 90 minutes. | 174 |
| SYS X YYYYYYYY MOTOR CURRENT OVERLOAD | Highest phase motor current exceeded overload setting continuously for 20 seconds | Highest of the 3 phases of motor current per compressor exceeded the compressor's 105% FLA ADJUST potentiometer setting on the VSD Logic Board continuously for 20 seconds | Controlled ramped shutdown. Locks out system on 1st fault. Will not restart until operator clears the fault using the keypad. | 175 |
| UNIT YYYYYYYY MOTOR CURRENT OVERLOAD | Highest phase motor current exceeded overload setting continuously for 30 seconds across all compressors | Highest of the 3 phases of motor current per compressor exceeded the compressor's overload ADJUST potentiometer setting continuously for 30 seconds | Immediate shutdown. Locks out all systems on 1st fault. Will not restart until operator clears the fault using the keypad. | 175 |
| SYS X YYYYYYYY GATE DRIVER | IGBT short circuit detected or gate driver power supply low | IGBT saturation voltage (VCE SAT) exceeded prescribed limit due to short circuit condition, or IGBT Gate Driver board power supply voltage fell below permissible limit | Immediate shutdown. Auto-restart safety. Locks out on 3rd fault in 90 minutes. | 175 |
| SYS X YYYYYYYY HIGH VSD BASEPLATE TEMP | IGBT baseplate temperature exceeded software trip point | Baseplate temperature exceeded limit — 218°F for 2 and 4 compressor chillers, 232°F for 3 compressor chillers | Controlled ramped shutdown. Auto-restart safety. Locks out on 3rd fault in 90 minutes. Fans and water pump remain energized until baseplate temperature falls below 165°F; restart allowed when temperature drops below this value. | 176 |
| UNIT YYYYYYYY HIGH VSD INTERNAL AMBIENT TEMP | VSD internal cabinet ambient temperature rose above cutout | VSD internal ambient temperature rose above the cutout of 158°F | Controlled ramped shutdown. Does not cause lockout. Restarts when internal ambient temperature drops 10°F below the cutout (148°F). | 176 |
| UNIT YYYYYYYY SINGLE PHASE INPUT VOLTAGE SYS X YYYYYYYY SINGLE PHASE INPUT VOLTS | One of three input line voltages missing | SCR Trigger Control board circuitry detected absence of any of the three-phase line voltages | Immediate shutdown. Does not cause lockout. Restarts when the single phase condition clears. | 176 |
| UNIT YYYYYYYY VSD LOGIC BOARD POWER SUPPLY | One or more DC power supplies to VSD Logic Board outside allowable limits | Monitored DC power supplies on the VSD Logic Board fell outside their allowable limits | Immediate shutdown. Auto-restart safety. Restarts after fault clears. Locks out on 3rd fault in 90 minutes. | 177 |
| SYS X YYYYYYYY VSD RUN RELAY | Hardware and software run signals did not match within 5-second window | Missing run signal not asserted within the 5-second window, or remaining run signal not disabled within 5 seconds after the VSD was shut down | Controlled ramped shutdown if running. Auto-restart safety. Autostarts after 120 second anti-recycle timer times out. Locks out on 3rd fault in 90 minutes. | 177 |
| UNIT YYYYYYYY VSD LOGIC BOARD FAILURE | PWM generator did not acknowledge voltage and frequency commands | System microprocessor did not receive handshake from PWM generator within 1.5 seconds of issuing the command | All systems immediately shut down. Auto-restart safety. Auto restarts after 120 second anti-recycle timer. Locks out on 3rd fault in 90 minutes. | 177 |
| UNIT YYYYYYYY VSD CT PLUG FAULT | CT plug not installed on VSD Logic Board | Jumper in CT plug not installed, causing a low value read on the digital input | Immediate shutdown or prevented from running. Auto-restart safety. Restarts after 120 second anti-recycle timer. Locks out on 3rd fault in 90 minutes. | 177 |
UNIT WARNINGS
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| UNIT WARNING: !! LOW BATTERY !! CHECK SETPOINTS/PROGRAM/OPTIONS/TIME | RTC battery voltage low at power-up | RTC battery determined to be low at micropanel power-up | All programmed setpoints, program values, time, schedule, and history buffers lost and reset to defaults. Unit prevented from running until MANUAL OVERRIDE key pressed. Anti-recycle timers set to default to allow time to check settings. Replace battery as soon as possible. | 180 |
| UNIT WARNING: INVALID NUMBER OF COMPRESSSORS SELECTED | No or multiple "Number of Compressors Select" jumpers installed | No jumpers installed or more than 1 jumper installed in the VSD wiring harness at power-up | Turn off both control panel and VSD control voltage. Install proper jumpers in the VSD wiring harness (see Page 136). | 183 |
| UNIT WARNING: INVALID SERIAL NUMBER ENTER UNIT SERIAL NUMBER | Chiller serial number not programmed or lost | Chiller Control Board replaced, EPROM changed, or factory programming lost | Contact YORK Product Technical Support immediately. Serial number entered using Service Key with factory password. Optimized IPLV chiller will only run in Standard IPLV mode until serial number is programmed. | 183 |
| UNIT WARNING: OPTIMIZED EFFICIENCY DISABLED - CONTACT YORK REPRESENATIVE | Optimized chiller programmed for standard control | High IPLV mode not enabled — serial number not programmed or option not activated | Contact YORK Product Technical Support or YORK ES Commercial. Special password required to enable optimized IPLV control via Service Key. | 183 |
UNIT SAFETIES
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| UNIT YYYYYYYY LOW AMBIENT TEMP | Ambient temperature below programmable low ambient cutout | Ambient temperature fell below the programmable Low Ambient Temp Cutout (only if enabled under OPTIONS key) | Controlled ramped shutdown. Auto-restart when temperature rises 2°F above cutout. Cannot cause lockout. Unit inhibited from starting when temperature below cutout + 2°F. | 184 |
| UNIT YYYYYYYY LOW LEAVING CHILLED LIQUID TEMP | Leaving chilled liquid temperature below freeze protection cutout | Leaving chilled liquid temperature dropped below the programmable cutout point (low flow conditions or improperly programmed setpoint values) | Controlled ramped shutdown. Auto-restart when chilled liquid temperature rises 4°F above cutout. Cannot cause lockout. Unit inhibited from starting when temperature below cutout + 4°F. | 185 |
| UNIT YYYYYYY VSD COMMUNICATIONS FAILURE | Chiller Control Board lost or never established communications with VSD Logic Board | No valid response received for 8 seconds during operation, or initialization data not received at power-up | Controlled ramped shutdown. Unit inhibited from starting until communications established. Automatically resets when Chiller Control Board receives a valid response from the VSD. | 185 |
SYSTEM SAFETIES (FAULTS)
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| SYS X YYYYYYYY HIGH DISCHARGE PRESSURE | Discharge pressure rose above software cutout threshold | Discharge pressure rose above 274 PSIG for 0.5 seconds | Controlled ramped shutdown. Restart allowed when discharge pressure falls to 259 PSIG. Inhibited from starting if pressure above 259 PSIG. Auto-restart after 120 second anti-recycle timer. Locks out after 3 faults in 90 minutes. | 186 |
| SYS X YYYYYY HPCO FAULT | Mechanical high pressure cutout contacts opened | Mechanical high pressure cutout opened at 297+/-8 PSIG | Immediate shutdown. Auto-restart after 120 second anti-recycle timer. Locks out after 3 faults in 90 minutes. HPCO resets (closes) at 230+/-10 PSIG. | 187 |
| SYS X YYYYYYYY LOW SUCTION PRESSURE | Suction pressure fell below programmable cutout | Suction pressure fell below the programmable cutout (typically 24 PSIG for chilled water applications); low refrigerant charge or low flow | Controlled ramped shutdown. Cutout ignored for first 30 seconds of run time; linearly ramped from 10% of cutout up to full value over next 3 minutes. Transient override provides additional 30-second grace period after 3.5 minutes. Auto-restart after 120 second anti-recycle timer. Locks out after 3 faults in 90 minutes. | 187 |
| SYS X YYYYYYYY LOW MOTOR CURRENT | Absence of motor current detected (<10%FLA) | Microprocessor detected motor current below 10%FLA, usually indicating compressor is not running | Controlled ramped shutdown. Safety ignored for first 10 seconds of operation. Auto-restart after 120 second anti-recycle timer. Locks out after 3 faults in 90 minutes. | 187 |
| SYS X YYYYYYYY HIGH DIFF OIL PRESSURE | Discharge-to-oil differential pressure rose above cutout | Discharge to Oil Differential Pressure rose above the cutout of 65 PSID (possibly dirty oil filter) | Controlled ramped shutdown. Safety ignored for first 90 seconds of run time. Auto-restart after 120 second anti-recycle timer. Locks out after 3 faults in 90 minutes. | 188 |
| SYS X YYYYYYYY LOW DIFF OIL PRESSURE | Oil-to-suction differential pressure fell below cutout | Differential between oil and suction pressure fell below the cutout (compressor not pumping sufficiently to push oil through lubrication system) | Controlled ramped shutdown. Safety ignored for first 60 seconds; cutout linearly ramped from 0 PSID to 30 PSID over 5–10 minutes based on ambient temperature. 30-second bypass below 50 Hz during rampdown. Auto-restart after 120 second anti-recycle timer. Locks out after 3 faults in 90 minutes. | 188 |
| SYS X YYYYYYYY HIGH DSCHARGE TEMP | Discharge temperature rose above cutout | Discharge temperature rose above 250°F | Controlled ramped shutdown. Inhibited from starting if discharge temperature above 200°F. Auto-restart after 120 second anti-recycle timer. Locks out after 3 faults in 90 minutes. | 188 |
| SYS X YYYYYYYY HIGH OIL TEMP | Oil temperature rose above cutout | Oil temperature rose above 225°F | Controlled ramped shutdown. Inhibited from starting if oil temperature above 175°F. Auto-restart after 120 second anti-recycle timer. Locks out after 3 faults in 90 minutes. | 189 |
| SYS X YYYYYYYY LOW SUCTION SUPERHEAT | Suction superheat fell below threshold indicating liquid floodback risk | One of: suction superheat <2.0°F with discharge superheat <15°F (run time <5 min, ramped cutout over 60 sec); suction superheat <2°F with discharge superheat <15°F for 10 sec (run time ≥5 min); suction superheat <0.5°F with discharge superheat >15°F for 60 sec (run time ≥5 min); suction superheat <5°F for 10 minutes | Controlled ramped shutdown. Ignored for first 30 seconds of operation. Auto-restart after 120 second anti-recycle timer. Locks out after 3 faults in 90 minutes. | 189 |
| SYS X YYYYYYYY LOW DISCHARGE SUPERHEAT | Discharge superheat fell below threshold indicating liquid floodback through economizer | After first 5 minutes of run time, discharge superheat fell below 10.0°F for 5 minutes | Controlled ramped shutdown. Ignored for first 5 minutes of operation. Auto-restart after 120 second anti-recycle timer. Locks out after 3 faults in 90 minutes. | 189 |
| SYS X YYYYYYYY SENSOR FAILURE: ZZZZZZZZZZZZ | Critical sensor reading out of range or not functioning properly | Critical sensor (transducer, level sensor, or motor winding temp sensor) reading out of range high or low. Possible values: SUCT PRESS, OIL PRESS, DSCH PRESS, LEVEL SENSOR, MOTOR TEMP X | Prevents system from running at start-up; faults and shuts down system while in operation if threshold exceeded. Auto-restart after 120 second anti-recycle timer. Locks out after 3 faults in 90 minutes. | 190 |
| SYS X YYYYYYYY HIGH MOTOR TEMP | Compressor motor temperature too high | Any compressor motor temperature sensor rose above 250°F | Controlled ramped shutdown. Inhibited from starting if motor temperatures above 240°F. Auto-restart after 120 second anti-recycle timer. Locks out after 3 faults in 90 minutes. | 190 |
| SYS X YYYYYYYY HIGH FLASH TANK LEVEL | Liquid level in flash tank too high | Tank level greater than 85% for 10 seconds | Controlled ramped shutdown. Safety ignored for first 15 seconds of operation. Auto-restart after 120 second anti-recycle timer. Locks out after 3 faults in 90 minutes. | 191 |
| SYS X YYYYYYYY CONTROL VOLTAGE | 115VAC control voltage to one system missing | System fuse removed or blown, causing loss of 115VAC supply to the affected system | Immediate shutdown of affected system. Does not cause lockout. Resets automatically when power is returned. | 191 |
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