Service Test - Carrier 38APS025 Manual

MODE ITEM EXPANSION
D.OIL Digital Oil Recover Mode
L.OUT OAT Below Lockout Temp
MD05 Ramp Load Limited
MD06 Timed Override in Effect
MD09 Slow Change Override
MD10 Minutes Off Time Active
MD14 Temperature Reset
MD15 Demand Limited
MD17 Low Temperature Cooling
MD18 High Temperature Cooling
MD21 High SCT Circuit A
MD22 High SCT Circuit B
MD23 Minimum Comp On Time
MD25 Low Sound Mode
MDTG Time Guard Active
SERVICE
The controls system allows for the oper-
Service Test —
ation of various components in a Service Test mode. While op-
erating in Service Test mode, outputs can be tested and various
components run to confirm proper operation. While operating
compressors in Service Test mode, the capacity control algo-
rithm and all safeties are active. Confirm airflow in the evapo-
rator before starting the unit in Service Test.
NOTE: Main power must be on for Service Test to function.
The Service Test function should be used to verify proper
operation of condenser fan(s), compressors, minimum load
valve solenoid (if installed), and remote alarm relay. To use the
Service Test mode, the Enable/Off/Remote Contact switch
must be in the OFF position. Use the display keys and Service
Test Mode and Sub-Mode Directory table in Appendix A to
enter the mode and display TEST. Press
OFF flashes. Enter the password if required. Use either arrow
key to change the TEST value to the ON position and press
. Place the Enable/Off/Remote Contact switch in the
ENTER
ENABLE position to begin Service Test. Press
the up or down key to enter the OUTS, CMPA or CMPB sub-
mode.
Table 62 — Operating Modes
DESCRIPTION
Digital compressor has been running
below standard Maximum A1 Unload
Time (Configuration UNIT MAX.T) for
more than 30 minutes. Digital compres-
sor will load to 100% for 30 seconds.
Ambient temperature is below field config-
urable setting, causing mechanical cool-
ing to be disabled.
Prevents rapid staging of compressors at
start-up
Unit is operating outside of normal occu-
pied time period
Supply air temperature is close to and
moving toward the Control Point
(Run Status VIEW CTPT)
Unit is prohibited from starting until the
timer has expired
Unit is operating with a modified set point Unit is operating with a modified set point
Unit capacity is being limited by a
Demand Limit command
Supply Air Temperature is decreasing
faster than 0.5 F (0.3 C) and the differ-
ence between the Supply Air Tempera-
ture and Control Point (Run
Status VIEW CTPT) exceeds a calcu-
lated value.
Supply Air Temperature and and its rate
of change are increasing, and the differ-
ence between the Supply Air Tempera-
ture and Control Point (Run
Status VIEW CTPT) exceeds a calcu-
lated value.
Circuit SCT exceeds a calculated limit
Compressor has not completed its mini-
mum run time
Not supported
Prevents rapid cycling of a compressor
twice so that
ENTER
and
ESCAPE
136
Digital compressor will load completely.
supply air temperature may be lower than
Control Point (Run Status VIEW
CTPT).
Unit is not allowed to start.
May not be able to supply air at the Con-
trol Point (Run Status VIEW CTPT)
Normal capacity control is enabled.
Capacity stage changes are prohibited.
Unit may not supply air at the Control
Point
(Run Status VIEW CTPT)
Unit is not allowed to start.
under normal capacity control.
Unit may not be able to deliver the desired
supply air temperature.
Unit may unload.
Unit will automatically load.
No additional stages of capacity will be
added. Unit may unload to lower SCT.
Compressor will remain running. Supply
Air Temperature may be lower than Con-
trol Point (Run Status VIEW CTPT).
Not Supported
May allow the unit to overshoot the set
point or not allow a compressor to start if
required.
Test the condenser fans, liquid line solenoids and alarm re-
lay by changing the item values from OFF to ON. These dis-
crete outputs are then turned off if there is no keypad activity
for 10 minutes. Use the arrow keys to select the desired per-
centage when testing Motormaster
seconds for the digital unloader solenoid, if equipped. All com-
pressor outputs can be turned on, but the control will limit the
rate by staging one compressor per minute. Minimum load
valve relays/solenoids, if installed, can be tested with the com-
pressors on or off. The relays under the CMPA or CMPB mode
will stay on for 10 minutes if there is no keypad activity. Com-
pressors will stay on until they are turned off by the operator.
The Service Test mode will remain enabled for as long as there
is one or more compressors running. All safeties are monitored
during this test and will turn a compressor, circuit or the ma-
chine off, if required. Any other mode or sub-mode can be ac-
cessed, viewed, or changed during the TEST mode. The
MODE item (Run Status VIEW) will display NO as long as
the Service mode is enabled. The TEST sub-mode value must
be changed back to OFF before the unit can be switched to En-
able or Remote Control for normal operation.
SYSTEM EFFECT
® V controller or number of