Start-Up, General; Unit Preparation; Additional Installation/Inspection; Return-Air Filters - Carrier 50FC 08-16 Series Service And Maintenance Instructions

Proceed as follows to inspect and prepare the unit for initial
start-up:
1. Remove all access panels.
2. Read and follow instructions on all WARNING,
CAUTION, and INFORMATION labels attached to, or
shipped with, unit.
3. Make the following inspections:
a. Inspect for shipping and handling damages such as bro-
ken lines, loose parts, or disconnected wires, etc.
b. Inspect for oil at all refrigerant tubing connections and
on unit base. Detecting oil generally indicates a refriger-
ant leak. Leak-test all refrigerant tubing connections
using electronic leak detector, halide torch, or liquid-
soap solution.
c. Inspect all field-wiring and factory-wiring connections.
Be sure that connections are completed and tight. Be
sure that wires are not in contact with refrigerant tubing
or sharp edges.
d. Inspect coil fins. If damaged during shipping and han-
dling, carefully straighten fins with a fin comb.
4. Verify the following conditions:
a. Make sure that condenser-fan blade are correctly posi-
tioned in fan orifice. See Condenser Fan Adjustment sec-
tion for more details.
b. Make sure that air filter(s) is in place.
c. Make sure that condensate drain trap is filled with water
to ensure proper drainage.
d. Make sure that all tools and miscellaneous loose parts
have been removed.

START-UP, GENERAL

Unit Preparation

Make sure that unit has been installed in accordance with installa-
tion instructions and applicable codes.
In addition to the base unit start-up (unit with electro-mechanical
control), there are a few steps needed to properly start-up units
with optional direct digital controls (DDC). The DDC's Service
Test function should be used to assist in the base unit start-up and
also allows verification of output operation. Controller configura-
tion is also part of start-up. This is especially important when field
accessories have been added to the unit. The factory pre-config-
ures options installed at the factory. There may also be additional
installation steps or inspection required during the start-up
process.

Additional Installation/Inspection

Inspect the field-installed accessories for proper installation, mak-
ing note of which ones do or do not require configuration changes.
Inspect the DDC Alarms for initial insight to any potential issues.
Refer to the Controls, Start-up, Operation and Troubleshooting In-
structions manual for the specific DDC. Inspect the SAT sensor
for relocation as intended during installation. Inspect special wir-
ing as directed below.

Return-Air Filters

Ensure correct filters are installed in unit (see Appendix B —
Physical Data). Do not operate unit without return-air filters.

Outdoor-Air Inlet Screens

Outdoor-air inlet screen must be in place before operating unit.

Compressor Mounting

Compressors are internally spring mounted. Do not loosen or re-
move compressor hold down bolts.

Internal Wiring

Check all electrical connections in unit control boxes. Tighten
as required.

Refrigerant Service Ports

Each unit system has two 1/4 in. SAE flare (with check valves)
service ports: one on the suction line, and one on the compressor
discharge line. Be sure that caps on the ports are tight.

Compressor Rotation

EQUIPMENT DAMAGE HAZARD
Failure to follow this caution can result in premature wear and
damage to equipment.
Scroll compressors can only compress refrigerant if
rotating in the right direction. Reverse rotation for
extended times can result in internal damage to the
compressor. Scroll compressors are sealed units and
cannot be repaired on site location.
On 3-phase units with scroll compressors, it is important to be cer-
tain compressor is rotating in the proper direction. To determine
whether or not compressor is rotating in the proper direction:
1. Connect service gauges to suction and discharge pressure
fittings.
2. Energize the compressor.
3. The suction pressure should drop and the discharge pres-
sure should rise, as is normal on any start-up.
If the suction pressure does not drop and the discharge pressure
does not rise to normal levels:
1. Note that the evaporator fan is probably also rotating in
the wrong direction.
2. Turn off power to the unit and install lockout tag.
3. Reverse any two of the unit power leads.
4. Re-energize to the compressor. Check pressures.
The suction and discharge pressure levels should now move to
their normal start-up levels.
NOTE: When the compressor is rotating in the wrong direc-
tion, the unit will make an elevated level of noise and will not
provide cooling.

Cooling

Set space thermostat to OFF position. To start unit, turn on main
power supply. Set system selector switch at COOL position and
fan switch at AUTO. position. Adjust thermostat to a setting be-
low room temperature. Compressor starts on closure of contactor.
Check unit charge. Refer to Refrigerant Charge section on
page 16.
Reset thermostat at a position above room temperature. Com-
pressor will shut off. Evaporator fan will shut off after a
30-second delay.
To shut off unit, set system selector switch at OFF position. Reset-
ting thermostat at a position above room temperature shuts unit off
temporarily until space temperature exceeds thermostat setting.
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CAUTION