| Document type | Operation Guide |
|---|---|
| Document number | 160.76-O1 |
| Equipment | YK Centrifugal Chiller |
| Brand | YORK |
| Revised | 2024-04-25 |
| File size | 3.3 MB |
Fault codes in this document
Troubleshooting
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| 1. Symptom: abnormally high discharge pressure | The temperature difference between the condensing temperature and water off condenser is higher than normal. | Air is in the condenser. | 30 | |
| 1. Symptom: abnormally high discharge pressure | The temperature difference between the condensing temperature and water off condenser is higher than normal. | Condenser tubes dirty or scaled. | Clean condenser tubes. Check water conditioning. | 30 |
| 1. Symptom: abnormally high discharge pressure | High discharge pressure. | High condenser water temperature. | Reduce condenser water inlet temperature. Check cooling tower and water circulation. | 30 |
| 1. Symptom: abnormally high discharge pressure | The temperature difference between condenser water on and water off is higher than normal, with normal evaporator pressure. | Insufficient condensing water flow. | Increase the quantity of water through the condenser to proper value. | 30 |
| 2. Symptom: abnormally low suction pressure | Insufficient charge of refrigerant. | Check for leaks and charge refrigerant into system. | 30 | |
| 2. Symptom: abnormally low suction pressure | The temperature difference between the leaving chilled water and the refrigerant in the evaporator is greater than normal with high discharge temperature. | Variable orifice problem. | Remove obstruction. | 30 |
| 2. Symptom: abnormally low suction pressure | The temperature difference between the leaving chilled water and the refrigerant in the evaporator is greater than normal with normal discharge temperature. | Evaporator tubes dirty or restricted. | Clean evaporator tubes. | 30 |
| 2. Symptom: abnormally low suction pressure | The temperature of chilled water is too low with low motor amperes. | Insufficient load for system capacity. | Check the motor operation of the pre-rotation vane and check the setting of the low water temperature cutout. | 30 |
| 3. Symptom: high evaporator pressure | Pre-rotation vanes fail to open. | Check the pre-rotation vane motor positioning circuit. | 30 | |
| 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. | 30 | |
| 4. Symptom: no oil pressure when system start button pushed | Oil pump running in wrong direction. | Check rotation of oil pump (Electrical Connections). | 30 | |
| 4. Symptom: no oil pressure when system start button pushed | Low oil pressure is displayed on the control center; the compressor does not start. | Oil pump not running. | Troubleshoot electrical problem with oil pump VSD. | 30 |
| 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. The transducer is defective. | Replace low or high oil pressure transducer. | 30 |
| 6. Symptom: oil pump vibrates or is noisy | Oil pump vibrates or is extremely noisy with some oil pressure when pressing the Oil Pressure display key. Note: When the oil pump is run without an oil supply, it vibrates and becomes extremely noisy. | Oil not reaching pump suction inlet in sufficient quantity. | Check oil level. | 30 |
| 6. Symptom: oil pump vibrates or is noisy | Oil pump vibrates or is extremely noisy with some oil pressure when pressing the Oil Pressure display key. | Worn or failed oil pump. | Repair or, if necessary, replace the oil pump. | 30 |
| 7. Symptom: reduced oil pump capacity | Oil pump pumping capacity. | Excessive end clearance pump. Other worn pump parts. | Inspect and replace worn parts. | 30 |
| 7. Symptom: reduced oil pump capacity | Oil pump pumping capacity. | The oil supply inlet is partially blocked. | Check the oil inlet for blockage. | 30 |
| 8. Symptom: oil pressure gradually decreases (noted by observation of daily log sheets) | When the oil pump VSD frequency increases to 55 + Hz to maintain target oil pressure. | Oil filter is dirty. | Change oil filter. | 30 |
| 9. Symptom: oil pressure system ceases to return an oil/refrigerant sample | Filter-drier in oil return system dirty. | Replace old filter-drier with new. | 30 | |
| 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. | 30 |
| 10. Symptom: oil pump fails to deliver oil pressure | No oil pressure registers when pressing the Oil Pressure display key when the oil pump runs. | Faulty oil pressure transducer. Faulty wiring/connectors. | Replace oil pressure transducer. | 31 |
Safety controls and panel warnings
| Code / display | Meaning | Cause | Action | Page |
|---|---|---|---|---|
| Oil heater thermostat (1HTR) | Protective thermostat, set to open at 180°F (82°C) to prevent overheating of the oil in the event of a control center component failure. | 15 | ||
| Leaving Chilled Liquid – Low Temperature Control | Safety control that shuts down the chiller. | Load continues to decrease after the pre-rotation vanes are entirely closed. | 16 | |
| Oil pressure safety cutout | Actuates and stops the system. | Excessive refrigerant in the oil causes violent oil foaming as the pressure within the system is lowered on starting (refrigerant boiling out of the oil); foam reaches the oil pump suction, so the bearing oil pressure fluctuates with possible temporary loss of lubrication. | 25 | |
| HOT | Unit shutting down on high oil temperature. | Change the oil filter element. Examine the oil filter element for the presence of aluminum particles. Aluminum gas seal rings can contact the impeller and account for some aluminum particles to accumulate in the oil filter, especially during the initial start up and first several months of operation. If aluminum particles continue to accumulate, contact Johnson Controls Service. | 37 | |
| OP | Unit shutting down on low oil pressure. | Change the oil filter element. Examine the oil filter element for the presence of aluminum particles. Aluminum gas seal rings can contact the impeller and account for some aluminum particles to accumulate in the oil filter, especially during the initial start up and first several months of operation. If aluminum particles continue to accumulate, contact Johnson Controls Service. | 37 | |
| Warning message to re-lubricate | OptiView panel warning message; at the programmed value plus 400 hours this feature shuts down the chiller if re-lubrication is not addressed. | Programmed number of motor operating hours reached (default value is 1000 hours). | Re-lubricate the motor bearings. In plants where chillers run 24/7, there is more than 16 days of advance warning prior to shutting down the chiller. | 40 |
| Bearing temperature warning | Warning issued when bearing temperature exceeds 65°C (normal operating temperature for grease lubricated bearings is 40°C to 65°C / 100°F to 150°F). Indicates either the bearings are in need of lubrication or something is wrong. If temperature reaches 70°C, it generally indicates some type of problem. | Bearing temperature exceeds 65°C. | Operation should be checked. | 44 |
| Bearing RTD shutdown | Bearing RTDs are normally set to shut down the motors at 90°C (194°F); once this temperature is reached, the bearings most likely have already been compromised. | Bearing temperature reaches 90°C (194°F). | 42 |
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