YORK YK — Oil - High dilution

The panel reads Oil - High dilution; some YK panels and service documentation print it as OIL - HIGH DILUTION. It appears in the safety fault messages of the control, and it is only active when Oil Quality Protection is enabled — where that option is off, the message cannot occur.

This is a safety fault. The control sets it when the chiller has been running for 10 minutes and the measured Oil Dilution is greater than the JCI Service programmable High Dilution Safety Trip Threshold, whose default is 15.0%. In other words, the oil is judged too diluted by refrigerant for the control to allow continued running.

• The oil dilution value has risen above the programmable High Dilution Safety Trip Threshold (default 15.0%) while the chiller has been running for 10 minutes.
• The fault can only be set on a chiller where Oil Quality Protection is enabled.

• High Dilution Safety Trip Threshold — programmable through JCI Service; the default is 15.0% oil dilution.
• Running-time condition — the dilution comparison is made after the chiller has been running for 10 minutes.
• Oil Quality Protection — must be enabled for this safety fault to be active.

The safety can only be acknowledged once the chiller has stopped. The manuals give the wording: The fault can be cleared when the chiller has stopped and the Clear Fault key is selected. On the interface described in the control guide, the Clear button is pressed next to the listed event on the Systems Details Screen instead.