York YK Style H Operation Manual page 182

SECTION 3 - DISPLAY MESSAGES
Oil – High Differential Pressure
The differential oil pressure increased to greater than
120.0 PSID while the oil pump was running. The dif-
ferential oil pressure is the difference between the
output of the Sump Oil Pressure transducer (system
low pressure) and the output of the Pump Oil Pressure
transducer (system high pressure). The chiller can be
started after the differential oil pressure decreases to
less than 90.0 PSID and the Clear Fault key is pressed
on the display.
Oil – Pump Pressure Transducer Out Of Range
The Pump Oil Pressure transducer (system high pres-
sure) is indicating a pressure that is less than 0.0 PSIG
or greater than 315.0 PSIG. This is outside the normal
operating range of the transducer. This generally indi-
cates a defective transducer. The chiller can be start-
ed after the transducer is indicating a pressure that is
within range and the Clear Fault key is pressed on the
display.
Oil – Sump Pressure Transducer Out Of Range
The Sump Oil Pressure transducer (system low pres-
sure) is indicating a pressure that is outside the normal
operating range of the transducer as follows:
• R134a is less than 0.0 PSIG or more than 315.0
PSIG.
This generally indicates a defective transducer. The
chiller can be started after the transducer is indicating a
pressure that is within range and the Clear Fault key is
pressed on the display.
Oil – Differential Pressure Calibration
The Sump and Pump oil pressure transducers indicated
a differential oil pressure of greater than 15.0 PSID
during the oil pressure transducer Auto-Zeroing period
that begins 10 seconds into System Prelube and lasts
for 3 seconds. This is indicative of a defective Sump
or Pump transducer, since the oil pump is not running
during this period and the actual differential oil pres-
sure is 0 PSID. The transducers are sensing the same
pressure during this period and their outputs should be
similar. The chiller can be started after the Clear Fault
key is pressed on the display.
182
Oil – Variable Speed Pump – Setpoint Not
Achieved
This is only applicable to chillers equipped with the
Variable Speed Oil Pump Drive. One of the follow-
ing conditions have occurred while in System Prelube,
System Run or System Coastdown. The chiller can be
started after the Clear Fault key is pressed on the dis-
play.
1. The differential oil pressure was less than 35.0
PSID for 5 continuous seconds during the last 10
seconds of the System Prelube period or during
the first 15 seconds of System Run.
-OR-
2. Anytime after the first 30 seconds of System Run,
the differential oil pressure was less than the Oil
Pressure Setpoint with the speed command from
the Microboard at 60Hz for 5 continuous seconds.
Control Panel – Power Failure
A Control Power failure has occurred. If the power
failure duration was less than the duration of the appli-
cable coastdown period (2.5 minutes standard; 15 min-
utes steam turbine), the remainder of the coastdown is
performed upon restoration of power. The chiller can
be started after the Clear Fault key is pressed on the
display. This message can indicate a Cycling (autore-
start after power failure) or Safety (manual restart af-
ter power failure) shutdown, depending upon Control
Center configuration. It indicates a cycling shutdown
when displayed in orange characters; safety shutdown
when displayed in red characters. The Control Center
is configured for auto-restart or manual restart after
power failure by a qualified Service Technician follow-
ing instructions in OptiView Control Center – Service
Instructions (Form 160.76-M1).
Motor Or Starter – Current Imbalance
The three phase compressor motor current imbalance
was greater than 30% continuously for 45 seconds. The
imbalance is not checked until the chiller has been run-
ning for at least 45 seconds and the average of the three
phases of motor current is greater than 80% of the pro-
grammed 100% chiller Full Load Amps. The average
is calculated as:
(Ia+Ib+Ic)
Iave =
FORM 160.76-O2
issue date: 6/15/2015
3
JOHNsON CONtROLs