On the display
The Status display shows SYS X YYYYYYYY HIGH OIL TEMP. X is the system number, and YYYYYYYY indicates that the system is either in a FAULT condition or in LOCKOUT. The fault tables print the message as High Oil Temp. — system fault 33, shown at the system panel — and the troubleshooting guide calls it HIGH OIL TEMPERATURE. The message belongs to the compressor shutdown control safeties (faults).
What it means
This is the High Oil Temperature Cutout. The manual states that it protects the compressor from insufficient lubrication. When a system's oil temperature rises above the cutout, that system faults and shuts down with a controlled ramped shutdown. Which style of shutdown you see depends on the soft shutdown setting: ramped soft shutdown when soft shutdown is disabled, soft ramped when soft shutdown is enabled.
Why it appears
- Defective oil temperature sensor — the first item the troubleshooting guide lists for HIGH OIL TEMPERATURE.
- Condenser fans not operating or running backwards.
- Dirty coils.
What to check
- Check the oil temperature sensor with an infrared thermometer to determine whether its reading is reasonable; a defective sensor is the first suspect in the troubleshooting guide.
- Check the condenser fans — the manual calls out fans that are not operating or running backwards.
- Check the coils and clean them if they are dirty. For this work the manual warns:
Always remove power to the chiller and assure the DC bus voltage has bled off
.
Setpoints and thresholds
- Cutout: a system faults and shuts down with a controlled ramped shutdown when its oil temperature rises above 225°F.
- Start inhibit: a system is inhibited from starting if its oil temperature is above 175°F.
- Shutdown type: ramped soft shutdown when soft shutdown is disabled; soft ramped when soft shutdown is enabled.
- Condenser fan staging with heat recovery (optimized IPLV 2 or 3 compressor units, oil temp sensor enabled): fan stages are prevented from decreasing between 175.0°F (79.4°C) and 185.0°F (85.0°C); above 185.0°F (85.0°C) fan stages increase at the fan delay timer intervals; below 175.0°F (79.4°C) the fans follow standard IPLV control.
Reset and restart
If YYYYYYYY shows FAULT, the system will restart when the fault clears. If it shows LOCKOUT, the system will not restart until the operator clears the fault using the keypad. A software change note adds that the High Oil Temperature Cutout fault will clear and be disabled when the Oil Temp Sensor is disabled.
Questions engineers ask
What oil temperature trips the High Oil Temp fault on a YORK YCAV?
A system faults and shuts down with a controlled ramped shutdown when its oil temperature rises above 225°F. The system is inhibited from starting while its oil temperature is above 175°F.
How do I clear the YCAV High Oil Temp fault?
If the display shows FAULT, the system restarts on its own once the fault clears. If it shows LOCKOUT, the operator must clear the fault using the keypad before the system restarts.
Why does my YCAV keep tripping on High Oil Temp?
The manual's troubleshooting guide lists three items: a defective oil temperature sensor, condenser fans that are not operating or running backwards, and dirty coils. Verify the sensor reading with an infrared thermometer, check the fans, then check and clean the coils.
What does SYS X YYYYYYYY HIGH OIL TEMP mean on the display?
X is the system number. YYYYYYYY shows whether that system is in a FAULT condition, which restarts when the fault clears, or in LOCKOUT, which requires the operator to clear the fault with the keypad.
Messages next to this one
The same message on other models
Source
Written from the manufacturer's manuals for the YORK YCAV; every number and designation on this page is checked against them before publication. The row of the manual this message comes from:
All YORK YCAV messages: fault codes · YORK YCAV documentation · YORK manuals