Table 39 - Start Inhibit Sensor Thresholds - York YCIV0157 Installation Operation & Maintenance

Section 8 - Micropanel
Low discharge superheat cutout fault
The Low Discharge Superheat Cutout helps protect the
compressor primarily from liquid floodback through
the economizer line due to a high flash tank level. It
also provides protection from liquid floodback through
the suction line in conjunction with the low superheat
safety. This safety is ignored for the first 5 minutes of
compressor operation.
After the first 5 minutes of run time, if the discharge
superheat falls below 10.0°F for 5 minutes, the sys-
tem will fault and shut down with a controlled ramped
shutdown.
The Status display fault message for this safety is
shown below:
SYS X YYYYYYYY LOW DISCHARGE SUPERHEAT
X indicates the system and YYYYYYY indicates the
system is in a "FAULT" condition and will restart when
the 120 second anti-recycle timer times out or "LOCK-
OUT" and will not restart until the operator clears the
fault using the keypad.
Sensor failure cutout fault
The Sensor Failure Cutout prevents the system from
running when a critical sensor (transducer, level sen-
sor, or motor winding temp sensor) is not function-
ing properly and reading out of range. This safety is
checked at start-up and will prevent the system from
running if one of the sensors has failed.
The sensor failure safety will also fault and shutdown
a system while in operation, if a safety threshold is ex-
ceeded or a sensor reads out of range (high or low).
Following is the Status display fault message.
SYS X YYYYYYYY SENSOR FAILURE:
ZZZZZZZZZZZZ
X indicates the specific system. YYYYYYYY
will either indicate the system is in a
"FAULT" condition and will restart when
the fault clears, or "LOCKOUT" after 3
faults and will not restart until the opera-
tor clears the fault using the keypad.
242
ZZZZZZZZZZZ indicates the failed sensor below:
• SUCT PRESS
• OIL PRESS
• DSCH PRESS
• LEVEL SENSOR
• MOTOR TEMP X *
* The Unit Setup Mode allows a specific motor temperature sensor
to be ignored, if it fails.
The start inhibit thresholds for each sensor are shown
in Table 39 on page 242.

Table 39 - Start inhibit sensor thresholds

LOW THRESH-
SENSOR
Suction
Transducer
Oil Transducer
Discharge
Transducer
Level Sensor
Motor Temp.
Sensor
High motor temperature cutout fault
The High Motor Temperature Cutout prevents a com-
pressor from running when its motor temperature is too
high. A system will fault and shut down when any com-
pressor motor temperature sensor rises above 250°F.
The system will be inhibited from starting if its mo-
tor temperatures sensors indicate temperatures above
240°F. If any single temperature sensor is being ig-
nored under the Unit Set-up Mode, that sensor will not
be utilized when evaluating motor temperature.
Below is a sample Status display fault message:
SYS X YYYYYYYY HIGH MOTOR TEMP
X indicates the system and YYYYYYY indicates the
system is in a "FAULT" condition and will restart when
the fault clears or "LOCKOUT" and will not restart un-
til the operator clears the fault using the keypad.
Form 201.23-NM2
Issue date: 12/19/2023
HIGH THRESH-
OLD OLD
0.3 VDC 4.7 VDC
0.3 VDC 4.7 VDC
0.3 VDC 4.7 VDC
3.0 mA 21.0 mA
0ºF 240ºF
Johnson Controls