| Document type | Operation Guide |
|---|---|
| Document number | 160.73-O2 |
| Equipment | YK Centrifugal Chiller |
| Brand | YORK |
| Revised | 2024-04-25 |
| File size | 1.5 MB |
Fault codes in this document
Table 2: Operational analysis chart
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| 1. SYMPTOM: ABNORMALLY HIGH DISCHARGE PRESSURE | Temperature difference between condensing temperature and water off condenser higher than normal. High discharge pressure. | Air in condenser. | 25 | |
| 1. SYMPTOM: ABNORMALLY HIGH DISCHARGE PRESSURE | Temperature difference between condensing temperature and water off condenser higher than normal. High discharge pressure. | Condenser tubes dirty or scaled. | Clean condenser tubes. Check water conditioning. | 25 |
| 1. SYMPTOM: ABNORMALLY HIGH DISCHARGE PRESSURE | Temperature difference between condensing temperature and water off condenser higher than normal. High discharge pressure. | High condenser water temperature. | Reduce condenser water inlet temperature. (Check cooling tower and water circulation.) | 25 |
| 1. SYMPTOM: ABNORMALLY HIGH DISCHARGE PRESSURE | Temperature difference between condenser water on and water off higher than normal, with normal evaporator pressure. | Insufficient condensing water flow. | Increase the quantity of water through the condenser to proper value. | 25 |
| 2. SYMPTOM: ABNORMALLY LOW SUCTION PRESSURE | Temperature difference between leaving chilled water and refrigerant in evaporator greater than normal with high discharge temperature. | Insufficient charge of refrigerant. | Check for leaks and charge refrigerant into system. | 25 |
| 2. SYMPTOM: ABNORMALLY LOW SUCTION PRESSURE | Temperature difference between leaving chilled water and refrigerant in evaporator greater than normal with high discharge temperature. | Variable orifice problem. | Remove obstruction. | 25 |
| 2. SYMPTOM: ABNORMALLY LOW SUCTION PRESSURE | Temperature difference between leaving chilled water and refrigerant in the evaporator greater than normal with normal discharge temperature. | Evaporator tubes dirty or restricted. | Clean evaporator tubes. | 25 |
| 2. SYMPTOM: ABNORMALLY LOW SUCTION PRESSURE | Temperature of chilled water too low with low motor amperes. | Insufficient load for system capacity. | Check prerotation vane motor operation and setting of low water temperature cutout. | 25 |
| 3. SYMPTOM: HIGH EVAPORATOR PRESSURE | High chilled water temperature. | Prerotation vanes fail to open. | Check the prerotation vane motor positioning circuit. | 25 |
| 3. SYMPTOM: HIGH EVAPORATOR PRESSURE | High chilled water temperature. | System overload. | Be sure the vanes are wide open (without overloading the motor) until the load decreases. | 25 |
| 4. SYMPTOM: NO OIL PRESSURE WHEN SYSTEM START BUTTON PUSHED | Low oil pressure displayed on control center; compressor will not start. | Oil pump running in wrong direction. | Check rotation of oil pump (Electrical Connections). | 25 |
| 4. SYMPTOM: NO OIL PRESSURE WHEN SYSTEM START BUTTON PUSHED | Low oil pressure displayed on control center; compressor will not start. | Oil pump not running. | Troubleshoot electrical problem with oil pump VSD. | 25 |
| 5. SYMPTOM: UNUSUALLY HIGH OIL PRESSURE DEVELOPS WHEN OIL PUMP RUNS | Unusually high oil pressure is displayed when the oil pressure display key is pressed when the oil pump is running. | High oil pressure transducer defective. | Replace low or high oil pressure transducer. | 26 |
| 6. SYMPTOM: OIL PUMP VIBRATES OR IS NOISY | Oil pump vibrates or is extremely noisy with some oil pressure when pressing OIL PRESSURE display key. | Oil not reaching pump suction inlet in sufficient quantity. | Check oil level. | 26 |
| 6. SYMPTOM: OIL PUMP VIBRATES OR IS NOISY | When oil pump is run without an oil supply it will vibrate and become extremely noisy. | Worn or failed oil pump. | Repair/Replace oil pump. | 26 |
| 7. SYMPTOM: REDUCED OIL PUMP CAPACITY | Oil pump pumping capacity. | Excessive end clearance pump. | Inspect and replace worn parts. | 26 |
| 7. SYMPTOM: REDUCED OIL PUMP CAPACITY | Oil pump pumping capacity. | Other worn pump parts. | Inspect and replace worn parts. | 26 |
| 7. SYMPTOM: REDUCED OIL PUMP CAPACITY | Oil pump pumping capacity. | Partially blocked oil supply inlet. | Check oil inlet for blockage. | 26 |
| 8. SYMPTOM: OIL PRESSURE GRADUALLY DECREASES (Noted by Observation of Daily Log Sheets) | When oil pump VSD frequency increases to 55 + hz to maintain target oil pressure. | Oil filter is dirty. | Change oil filter. | 26 |
| 9. SYMPTOM: OIL PRESSURE SYSTEM CEASES TO RETURN AN OIL/REFRIGERANT SAMPLE | Oil refrigerant return not functioning. | Filter-drier in oil return system dirty. | Replace old filter-drier with new. | 26 |
| 9. SYMPTOM: OIL PRESSURE SYSTEM CEASES TO RETURN AN OIL/REFRIGERANT SAMPLE | Oil refrigerant return not functioning. | Jet or orifice of oil return jet clogged. | Remove jet, inspect for dirt. Remove dirt using solvent and replace. | 26 |
| 10. SYMPTOM: OIL PUMP FAILS TO DELIVER OIL PRESSURE | No oil pressure registers when pressing OIL PRESSURE display key when oil pump runs. | Faulty oil pressure transducer. | Replace oil pressure transducer. | 26 |
| 10. SYMPTOM: OIL PUMP FAILS TO DELIVER OIL PRESSURE | No oil pressure registers when pressing OIL PRESSURE display key when oil pump runs. | Faulty wiring/connectors. | 26 |
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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.