Trane Ascend ACR Series User Manual

AC-SVX001A-EN
95
Table 27. Diagnostics — main processor (continued)
Diagnostic
Name
Affects
Target
Severity
Persistence
Active
Modes
[Inactive
Modes]
Criteria
Reset
Level
Low
Evaporator
Temp (Unit Off)
– Ckt2
Evap Pump Special Action
NonLatch
Unit in Stop
Mode, or in
Auto Mode and
No Ckt's
Energzd [Any
Ckt Energzd]
The respective circuit’s “Chiller Off Cycle Freeze
Protection Integral” was seen to be higher than ½ of
its trip value while the chiller is in the Stop mode, or
in Auto mode with no compressors running, for one
minute and more. The COCFP integral is increased if
the Average of the Evap Water Temperatures and the
Evap Refrigerant Pool Temp is below the value of the
Low Evap Rfgt Temp Cutout + 4°F. Energize Evap
Water Pump and Off-Cycle Freeze Avoidance Request
Relay until diagnostic auto resets, then return to
normal evap pump control and de-energize the
Freeze Avoidance Request. Automatic reset occurs
when the respective Evap Rfgt Pool Temp rises 2°F
(1.1°C) above the LERTC cutout setting AND the
COCFP Integral is less than 1/3 of its trip value. This
diagnostic even while active, does not prevent
operation of either circuit. (At each circuit shutdown,
the COCFP integral is initialized to the LERTC
integral)
Remote
Low
Evaporator
Water Temp
(Unit Off)
Evap Pump and
Freeze
Avoidance
Request Relay
Info and
Special Action
NonLatch
Unit in Stop
Mode, or in
Auto Mode and
No Ckt(s)
Energzd [Any
Ckt Energzd]
Either the entering or leaving evaporator water temp
fell below the leaving water temp cutout setting for
30 °F-seconds while the Chiller is in the Stop mode,
or in Auto mode with no compressors running.
Energize Freeze Avoidance Request Relay and Evap
Water Pump Relay until diagnostic auto resets, then
de-energize the Freeze Avoidance Request Relay and
return to normal evap pump control. Automatic reset
occurs when both temps rise 2F (1.1C) above the
cutout setting for 5 minutes, or either circuit starts.
This diagnostic even while active, does not prevent
operation of either circuit
Remote
Low
Evaporator
Water Temp:
Unit On
Chiller
Immediate
Shutdown and
Special Action
NonLatch
Any Ckt[s]
Energzd [No
Ckt(s)
Energzd]
The evaporator entering or leaving water temp fell
below the cutout setpoint for 30° F-seconds while the
compressor was running. Automatic reset occurs
when both of the temperature rises 2 F (1.1C)
above the cutout setting for 2 minutes. This
diagnostic shall not de-energize the Evaporator
Water Pump Output
Remote
Low Oil Flow -
Cprsr 1A
Circuit Immediate Latch
Cprsr
Energized and
Delta P above
15 Psid
The oil pressure transducer for this compressor was
indicating an unacceptable oil pressure drop as a %
of the available oil pressure to move oil, suggesting
significantly reduced oil flow to the compressor.
Possible root causes include oil line service valve
closed or restricted, dirty or restricted oil filter, or
compressor oil line kepner valve malfunction
Local
Low Oil Flow -
Cprsr2A
Circuit Immediate Latch
Cprsr
Energized and
Delta P above
15 Psid
The oil pressure transducer for this compressor was
indicating an unacceptable oil pressure drop as a %
of the available oil pressure to move oil, suggesting
significantly reduced oil flow to the compressor.
Possible root causes include oil line service valve
closed or restricted, dirty or restricted oil filter, or
compressor oil line kepner valve malfunction
Local
DDiiaaggnnoossttiiccss

Trane Ascend ACR Series Specifications

General

Brand	Trane
Model	Ascend ACR Series
Category	Chiller
Language	English