Carrier VECTOR 6500 Operation & Service Manual page 239

Alarm
Steps
NO.
243 SUCTION/EVAP CALIBRATE ERROR
•
TRIGGER–ON: There is an error in either or both of the Suction Pressure (CSP) or Evaporator
Pressure (EVOP) Sensor Calibration values stored in the microprocessor memory. Note that neither
of these transducers can be calibrated manually. This is an error in the microprocessor.
•
UNIT CONTROL: Alarm only.
•
RESET CONDITION: Auto Reset when both Suction and Evaporator Pressure transducers are
reading correctly or alarm may be manually reset via keypad or by turning the unit off, then back on
again.
NOTE: Follow the steps below until a problem is found. Once a repair or correction has been made, the active
alarm should clear itself (see reset condition above). Operate the unit through the appropriate modes to see if
any active alarm occurs. Continue with the steps below as necessary.
1 Check Suction Pressure (CSP) and Evaporator Pressure (EVOP) Readings
a. Check Suction and Evaporator
Pressure Readings in the Unit Data.
b. Install manifold gauge set and
check and compare compressor
suction & evaporator pressures with
those shown on the microprocessor
display.
2 Reset Microprocessor
a. Place the Main Power switch in the
OFF position for 30 seconds, then
back to the desired position.
b. Wait 2-3 minutes, then check to see if
A-243 becomes active again.
c. Disconnect positive battery cable
from the battery, wait 30 seconds,
then reconnect and place the Main
Power
position.
d. Wait 2-3 minutes, then check to see if
A-243 becomes active again.
e. Valid readings are not appearing for
either or both the Suction and
Evaporator Pressures in the Unit
Data.
62-11389
Alarm/Cause
switch in the desired
7−106
Corrective Action
Must read valid data.
Suction and Evaporator Outlet Pressures must have
the same reading on gauges & on microprocessor
display.
NOTE: Microprocessor Suction (CSP) and Evap-
orator (EVOP) pressure readings have a maxi-
mum value of 100 psig (7.5 bar.) The actual pres-
sure must be lower than 100 psig in order to per-
form this test.
Microprocessor powers up OK
Suction and Evaporator pressure values are reading
OK when compared to test gauges.
Alarm is cleared.
Microprocessor powers up OK
Suction and Evaporator pressure values are reading
OK when compared to test gauges.
Alarm is cleared.
Download and replace microprocessor. Refer to
Section 5.7.