Carrier 50TCA04-A07 - Manual (Page 41)

41
4. Verify the following conditions:
a. Make sure that condenser--fan blade are correctly
positioned in fan orifice. See Condenser--Fan
Adjustment section on page 11 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
installation instructions and applicable codes.
Return--Air Filters
Make sure correct filters are installed in unit (see
Appendix II -- 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 remove 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” 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
On 3--phase units with scroll compressors, it is important
to be certain 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 pres-
sure fittings.
2. Energize the compressor.
3. The suction pressure should drop and the discharge
pressure 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
direction, 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 below room temperature.
Compressor starts on closure of contactor.
Check unit charge. Refer to Refrigerant Charge section on
page 7.
Reset thermostat at a position above room temperature.
Compressor will shut off. Evaporator fan will shut off
after a 30--second delay.
TO SHUT OFF UNIT
Set system selector switch at OFF position. Resetting
thermostat at a position above room temperature shuts
unit off temporarily until space temperature exceeds
thermostat setting.
Heating
To start unit, turn on main power supply.
Set system selector switch at HEAT position and set
thermostat at a setting above room temperature. Set fan at
AUTO position.
First stage of thermostat energizes the first--stage electric
heater elements; second stage energizes second--stage
electric heater elements, if installed. Check heating effects
at air supply grille(s).
If electric heaters do not energize, reset limit switch
(located on evaporator--fan scroll) by pressing button
located between terminals on the switch.
TO SHUT OFF UNIT -- Set system selector switch at OFF
position. Resetting thermostat at a position below room
temperature temporarily shuts unit off until space
temperature falls below thermostat setting.
Ventilation (Continuous Fan)
Set fan and system selector switches at ON and OFF
positions, respectively. Evaporator fan operates
continuously to provide constant air circulation.
START--UP, PREMIERLINK CONTROLS
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal
injury or death.
The unit must be electrically grounded in accordance
with local codes and NEC ANSI/NFPA 70 (American
National Standards Institute/National Fire Protection
Association.)
!
WARNING
50TC