Carrier WeatherExpert 48N2 Controls, Start-Up, Operation, Service, And Troubleshooting page 260

Temperatures / Pressures
(Record information from the Pressures and Temperatures modes when unit is in a stable operating condition.)
Supply Air Temperature - Cooling
Gas Heating Supply Air Temperature
Electric Heating Supply Air Temperature
Hydronic Heating Supply Air Temperature
Outdoor-Air Temperature
Return-Air Temperature
Gas Inlet Pressure (48N only)
Gas Manifold Pressure (48N only)
Suction Pressure
Discharge Pressure
Liquid Pressure
Return Gas Temperature
Refrigerant Superheat
Upper Coil
Lower Coil
General:
Verify refrigerant charge is correct on both circuits per start-up manual

Verify compressor oil levels are correct per start-up manual

Leak check unit. Locate, repair and report any refrigerant leaks

Verify that voltage is within unit nameplate range

Verify that control transformer primary connection is set for proper voltage

Control transformer secondary voltage = __________

Verify that optional CCN or BACnet wiring is temporarily disconnected for start-up

(Reconnect once unit is started)
Verify completion of all elements of controls 'service test'

Record all configuration settings on sheets CL-5 to CL-12

Provide operating instructions to owner's personnel. Instruction Time ________ hours.

III. Service Test
The units are equipped with a Service Test feature, which is intended to allow a service person to force the unit into different modes of
operation. To use this feature, enter the Service Test category on the Navigator display and place the unit into the test mode by changing
Service Test Ý TEST from OFF to ON. This TEST command turns the unit off (hard stop) and allows the unit to be put in a manual
control mode. The display will prompt for the password before allowing any change. The default password is 1111. Once the unit enters
the Service Test mode, the unit will shut down all current modes.
Operation in the Service Test mode is sub-menu specific except for the INDP submenu. Leaving the sub-menu while a test is being per-
formed and attempting to start a different test in the new sub-menu will cause the previous test to terminate. When this happens, the new
request will be delayed for 5 seconds. For example, if compressors were turned on under the COOL sub-menu, any attempt to turn on
heating stages within the HEAT sub-menu would immediately turn off the compressors and 5 seconds later the controller would honor
the requested heat stages. However, it is important to note that the user can leave a Service Test mode to view any of the local display
menus (Run Status, Temperatures, Pressures, Setpoints, Inputs, Outputs, Configuration, Time Clock, Operating Modes, and
Alarms) and the control will remain in the Service Test mode.
NOTE: The unit is shipped with the unit control disabled. To enable the control, set Local Machine Disable (Service Test Ý
STOP) to 'No'.
Via the Navigator control interface, scroll down to the 'Service Test' mode. Press <Enter> to see 'TEST'. Change 'OFF' to 'ON'.
Scroll down to 'INDP' and begin the test procedure. After completing 'INDP', proceed through the tests in the remaining
groups; 'FANS', 'ACT.C', 'HMZR', 'EXVS', 'COOL', and 'HEAT'. Note that an 'Auto-Component' automated version of the
test procedure is available under 'AC.DT', and may be used as an alternative to the manual procedure. Investigate and resolve
as needed any operations found to be not performing as intended.
___________ F
___________ F (48N only)
___________ F (50N only, if equipped)
___________ F (50N only, if equipped)
___________ F
___________ F DB (Dry Bulb)
___________ in. wg
Low Fire ___________ in. wg
Circuit A
SP.A ______________ psig
DP.A ______________ psig
LP.A ______________ psig
RGT.A ______________ F (Units with digital scroll only)
______________ F
______________ F
___________ F WB (Wet Bulb)
High Fire ___________ in. wg
Circuit B
SP.B ______________ psig
DP.B ______________ psig
LP.B ______________ psig
______________ F
______________ F
CL-4