Trane Ascend ACR Series Installation, Operation And Maintenance Manual page 89

Table 27. Diagnostics — main processor (continued)
Affects
Diagnostic
Target
Name
Evap Rfgt Pool
Temp Sensor Circuit
Error – Ckt2
Evap Spillover
Liquid Level Circuit
Sensor – Ckt1
Evap Spillover
Liquid Level Circuit
Sensor – Ckt2
Evap Water
Flow (Entering
None
Water Temp)
Evaporator
Approach Error Circuit
– Ckt1
Evaporator
Approach Error Circuit
– Ckt2
Evaporator
Entering Water
Chiller
Temp Sensor
Evaporator
Leaving Water
Chiller
Temp Sensor
Evaporator
Water Flow Chiller
Lost
AC-SVX001A-EN
Severity
Persistence
Info and
Latch
Special Action
Normal Latch
Normal Latch
Info NonLatch
Immediate Latch
Immediate Latch
Normal Latch
Normal Latch
Immediate NonLatch
Active
Modes
[Inactive
Modes]
The evaporator refrigerant pool temperature sensor
is indicating a temperature significantly warmer than
the evaporator entering water temperature (by more
than 7.2°F for 5 continuous min excluding ckt
Ckt Energized nonoperation and a 2 min ignore time relative to ckt
[Ckt Not startup). While this diagnostic is active, it will
Energized invalidate the evaporator pool temperature sensor.
Freeze protection functions (i.e. freeze diagnostics
and Evap Pump Override) will default to the
respective evaporator pressure transducer and its
calculated saturation temperature
All
All
The entering evaporator water temp fell below the
leaving evaporator water temp by more than 2°F for
180 °F-sec, minimum trip time 30 seconds. It can
Any Ckt
warn of improper flow direction through the
Energized [ No
evaporator, misbound water temperature sensors,
Ckts
improper sensor installation, partially failed sensors,
Energized]
or other system problems. Note that either entering
or leaving water temp sensor or the water system
The Evaporator approach temperature for the
respective circuit (ELWT – Evap Sat Temp Ckt 1) is
negative by more than 10°F for 1 minute
Respective
continuously while the circuit / compressor is
circuit running
operating. Either the Evap Leaving Water Temp
sensor, or Evap Suction Rfgt Pressure Transducer Ckt
The Evaporator approach temperature for the
respective circuit (ELWT – Evap Sat Temp Ckt 2) is
negative by more than 10°F for 1 minute
Respective
continuously while the circuit / compressor is
circuit running
operating. Either the Evap Leaving Water Temp
sensor, or Evap Suction Rfgt Pressure Transducer Ckt
Bad Sensor or LLID. Note: Entering Water Temp
Sensor is used in EXV pressure control as well as ice
All
making so it must cause a unit shutdown even if ice
or CHW reset is not installed
All
a. The Evaporator water flow switch input was open
for more than 6 contiguous seconds (or 15 seconds
[All Stop for thermal dispersion type flow switch). b. This
modes] diagnostic does not de-energize the evap pump
output. c. 6 seconds of contiguous flow shall clear
D D i i a a g g n n o o s s t t i i c c s s
Criteria
Bad Sensor or LLID
Bad Sensor or LLID
could be at fault
1 is in error
2 is in error
Bad Sensor or LLID
this diagnostic
Reset
Level
Local
Remote
Remote
Remote
Remote
Remote
Remote
Remote
Remote
89