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JOHNSON CONTROLS
139
SECTION 2 – OPTIVIEW CONTROL CENTER
FORM 160.79-O3
ISSUE DATE: 11/09/2018
2
“EVAPORATOR – TRANSDUCER OR TEMPER-
ATURE SENSOR”
A possible defective Evaporator pressure Transducer
or Refrigerant Temperature Sensor has been detected.
The Control Center converts the evaporator pressure to
a Saturated Temperature value and compares this val-
ue to the optional Evaporator Refrigerant Temperature
Sensor. If the difference between these temperatures
is greater than 3.0°F, continuously for 1 minute, this
shutdown is performed. This check is only performed
under the following conditions:
• Chiller has been running for at least 10 minutes
• Evaporator Refrigerant temperature (RT7) has
been enabled by a Service technician
• Not in Brine cooling mode
• Smart Freeze is enabled
• Evaporator Temperature Sensor (RT7) or Evapo-
rator Saturation Temperature is indicating a tem-
perature of <32.0°F
The chiller can be started after the temperatures are
within 3.0°F of one another and the Operator presses
the Clear Faults button.
“DISCHARGE #1 – HIGH PRESSURE CON-
TACTS OPEN”
The contacts of the electro-mechanical high pressure
switch (HP1, located in the discharge line of compres-
sor #1) have opened because it detected a pressure
>180.0 psig. The contacts will automatically close
when the discharge pressure decreases to < 120.0 psig
and the Operator presses the Clear Faults button.
“DISCHARGE #2 – HIGH PRESSURE CON-
TACTS OPEN”
The contacts of the electro-mechanical high pressure
switch (HP2, located in the discharge line of compres-
sor #2) have opened because it detected a pressure
>180.0 psig. The contacts will automatically close
when the discharge pressure decreases to < 120.0 psig
and the Operator presses the Clear Faults button.
“DISCHARGE #1 – HIGH TEMPERATURE”
The chiller (both compressors) has shutdown because
the discharge temperature of compressor #1, as sensed
by thermistor RT2, has increased to >220.0 ºF. The
chiller can be started after the temperature decreases
to <220.0 ºF and the Operator presses the Clear Faults
button.
If compressor #1 is locked out using the Lockout key
on the Capacity Compressor Cycling Screen, this fault
does not cause compressor #2 to shutdown or prevent
it from starting. When this fault occurs on a locked-out
compressor, it is displayed as a warning. This allows
the user to know that a fault exists on the locked-out
compressor. The condition must be corrected prior to
the lockout being removed from the compressor. If it
is not, the warning condition will revert back to a shut-
down as soon as the lockout is removed and will cause
the chiller to trip.
“DISCHARGE #2 – HIGH TEMPERATURE”
The chiller (both compressors) has shutdown because
the discharge temperature of compressor #2, as sensed
by thermistor RT8, has increased to >220.0 ºF. The
chiller can be started after the temperature decreases
to <220.0 ºF and the Operator presses the Clear Faults
button.
If compressor #2 is locked out using the Lockout key
on the Capacity Compressor Cycling Screen, this fault
does not cause compressor #1 to shutdown or prevent
it from starting. When this fault occurs on a locked-out
compressor, it is displayed as a warning. This allows
the user to know that a fault exists on the locked-out
compressor. The condition must be corrected prior to
the lockout being removed from the compressor. If it
is not, the warning condition will revert back to a shut-
down as soon as the lockout is removed and will cause
the chiller to trip.
“DISCHARGE #1 – LOW TEMPERATURE”
The chiller (both compressors) has shutdown because
the discharge temperature of compressor #1, as sensed
by thermistor RT2, has decreased to <30.0 ºF. The
chiller can be started after the temperature increases
to >30.0ºF and the Operator presses the Clear Faults
button.