Carrier 48FC Series Controls, Start-Up, Operation And Troubleshooting page 30

Alert A203 – DIRTY FILTER
This alert occurs when the Filter Status switch senses a plugged
filter for 5 continuous seconds after the indoor fan has been
running for 10 seconds or if the fan has run for longer than the
change filter time. Because the Dirty Air Filter switch can be
configured normally opened or closed, the switch might be open or
closed. Verify that the configurations are set correct, verify the
wiring and filter status switch. The hose should be connected to the
low side of the switch. The alert resets automatically if it was
tripped due to the filter switch. If the alert is tripped because of the
timer, it will need to be reset after the filter has been replaced or
inspected. Rest the time with the RESET FILTER TIME point is
located under RUN STATUS  GENERAL or INPUTS 
GENERAL INPUTS.
Fault F204 – REMOTE SHUTDOWN
This fault occurs when the remote shutdown input is either open or
closed depending upon its configuration and configured to set a
fault. This fault is usually caused by an auxiliary emergency device
that is trying to shut down the unit. This will cause a unit shutdown
condition. Verify that the configuration is set correct, verify the
wiring and auxiliary device. This fault resets automatically.
Fault F205 – IDF MANUAL LIMIT TRIP
This fault occurs when the indoor fan limit switch input is lost. The
switch is a manual rest limit that is normally closed. This fault is
usually caused by excess heat seen at the indoor fan. This fault will
cause a unit shutdown condition. Since the switch is manual reset
the button on the switch will have to be reset before reseting this
fault in the software.
Fault F206 – PHASE MONITOR TRIP
This fault occurs when the phase monitor input is either open or
closed depending upon its configuration. This fault is usually
caused by loss of phase or improper phasing of a 3 phase power
supply. This will cause a unit shutdown condition. Verify that the
configuration is set correct, verify the wiring and supply power.
This fault resets automatically.
Alert A210 – GENERAL STATUS
This alert occurs when the general status input is either open or
closed depending upon its configuration and configured to set a
alert. This alert is usually caused by an auxiliary switch device that
is trying to send a warning about the unit. Verify that the
configuration is set correct, verify the wiring and auxiliary device.
This alert resets automatically.
Fault F211 – GENERAL STATUS
This fault occurs when the general status input is either open or
closed depending upon its configuration and configured to set a
fault. This fault is usually caused by an auxiliary switch device that
is trying to shut down the unit. This will cause a unit shutdown
condition. Verify that the configuration is set correct, verify the
wiring and auxiliary device. This fault resets automatically.
Fault F310 – CIRA DOWN DUE TO FAIL
This fault occurs when both compressors on circuit A have 3
strikes. Investigate the alerts that caused the strikes to occur, and
correct or test as needed. Manual alarm reset or power cycle is
required to rest this fault.
Fault F311 – CIRA LOW CHARGE
This alert occurs when the compressors are off and both the
discharge and suction pressure are less than the low charge level
(LOW CHARGE LEVEL) and OAT is greater than the low charge
limit (NO LOW CHARGE OAT). The cause of the alert is usually
low refrigerant pressure or faulty pressure transducers. This alert
only occurs when the compressor is OFF because the low
refrigerant pressure alert will handle this situation when the
compressor is operating. Manual alarm reset or power cycle is
required to rest this fault.
Alert A312 – CIR.A UNEXPECTED OFF
These alerts occur when the suction pressure raises the configured
amount and the pressure ratio drop the configured amount both in
a 10 second window during compressor operation. When this
occurs, the control turns off the compressors and logs a strike for
which compressor that was on. This alerts reset automatically. The
possible causes are: high- -pressure switch (HPS) open (the HPS is
wired in series with compressor relays on the MBB), compressor
internal protection is open, or a wiring error (a wiring error might
not allow the compressor to start).
Alert A313 – CIR.A HIGH DISCHARGE
This alert occurs when the discharge pressure is greater than the
configured CIR.A SDP LIMIT amount. This alert resets
automatically when the pressure falls 20 psig below the threshold.
When running both compressors the control will remove A1 and
add a strike to it. The control will also set the ODFs to the high
cool speed. The cause of the alert is usually an overcharged system,
high outdoor ambient temperature coupled with dirty outdoor coil,
plugged filter drier, or ODF speeds being set too low.
Alert A314 – CIR.A HPS TRIP
This alert occurs when the discharge high pressure switch opens.
This alert resets automatically when the pressure falls below the
switch threshold and the switch closes for 3 minutes. The control
will add a strike for which ever compressors were on. The control
will also set the ODFs to the high cool speed. The cause of the alert
is usually an overcharged system, high outdoor ambient
temperature coupled with dirty outdoor coil, plugged filter drier, or
ODF speeds being set too low.
Alert A315 – CIR.A LOW DISCHARGE
This alert occurs when the discharge temperature is less than the
OAT plus the configured LOW DISCHARGE LEV amount. This
alert resets automatically. The control will add a strike for which
ever compressors were on. The cause of the alert is usually an
undercharged system, low outdoor ambient temperature coupled
with dirty outdoor coil, plugged filter drier, or ODF speeds being
set too high.
Alert A316 – CIR.A LOW SUCTION
This alert occurs when the compressor is operating and the
evaporating temperature (converted from the suction pressure) is
less than configured low suction control levels, LOW SUC
LEVEL 1, LOW SUC LEVEL2, or LOW SUC LEVEL3. The
circuit SST value must be less than LOW SUC LEVEL 1 (for 5
minutes), LOW SUC LEVEL 2 (for 4 minutes), or LOW SUC
LEVEL 3 (for 3 minutes when using the economizer and 1.5
minutes when not using the economizer) for the alert to occur.
When the outdoor temperature is less than 40_F, the above values
are reduced 1_F for every 2_F OAT is below 40_F. All the above
timers will reset if the suction temperature rises above LOW SUC
OK TEMP for 1 minute. This alert causes a strike for the respective
circuit. This alert will activate when the coil becomes frosted.
However, during the 15- -minute reset period, the coils will thaw
and strike should clear and restart if there is nothing else wrong
with the circuit. The alert resets automatically. The cause of the
alert is usually low refrigerant charge, dirty filters, evaporator fan
operating backwards, loose or broken belt, plugged filter drier,
faulty transducer, excessively cold return air, or stuck open
economizer when the ambient temperature is low.
Alert A317 – CIR.A PRESSURE RATIO
This alert occurs when the Circuit A pressure ratio is less than the
configured MIN PRESSURE RATIO amount. This alert resets
automatically. The control will add a strike for which ever
compressors were on. The cause of the alert is usually an
undercharged system, low outdoor ambient temperature coupled
with dirty outdoor coil, plugged filter drier, or ODF speeds being
set too high.
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