Carrier 38TMA - Manual (Page 4)

CONNECT GROUND AND POWER WIRES
Connect ground wire to ground connection in control box for
safety. Connect power wiring to contactor as shown in Fig. 4.
NOTE: Use No. 18 AWG color-coded, insulated (35 C min) wire.
If thermostat is located more than 100 ft from unit as measured
along the control voltage wires, use No. 16 AWG color-coded
wires to avoid excessive voltage drop.
CONNECT CONTROL WIRING
Route 24-voIt control wires through control wiring grommet and
connect to brown and blue pigtails supplied in unit splice box (Fig.
5.)
Use furnace or fan coil transformer as 24-volt supply for system as
shown in Fig. 5, or use accessory transformer. Most systems
require minimum 40 va, except 60 va is required for 048 and 060
size units or units installed with liquid line solenoid.
Step 6—Compressor Crankcase Heat
A crankcase heater is required if the refrigerant tubing is longer
than 50 ft (15.24m).
Step 7—Install Electrical Accessories, if any
Refer to the individual instructions packaged with the kit or
accessory when installing.
Step 8—Start-Up
1. When equipped with a crankcase heater, energize heater a
minimum of 24 hours before starting unit. To energize heater
only, set thermostat at OFF position and close electrical
disconnect to outdoor unit.
2. Fully back seat (open) liquid and vapor tube service valves.
3. Unit is shipped with valve stem(s) front seated, and caps
installed. Replace stem caps after system is opened to refrig­
erant flow (back seated). Replace caps finger-tight and tighten
additional 1/6-tum with wrench.
4. Close electrical disconnects to energize system.
5. Set room thermostat at desired temperature. Be sure set point
is below indoor ambient temperature.
6. Set room thermostat at COOL and fan switch at FAN or
AUTO, as desired. Operate unit for 15 minutes. Check system
refrigerant charge. See Refrigerant Charging.
Step 9—Checking Charge
Factory charge is shown on unit rating plate.
A CAUTION
Do not vent refrigerant to atmosphere. Recover during system
repair or final unit disposal.
A WARNING
Service valve gage ports are not equipped with Schrader
valves. To prevent personal injury, make sure gage manifold
is connected to the valve gage ports before moving valves off
fully back seated position. Wear safety glasses and glove
when handling refrigerant.
A CAUTION
I Compressor damage may occur if system is overcharged. |
Adjust charge by following procedure shown on Superheat Charg­
ing Tables located on unit information plate.
Step 10—Leave User’s Manual with Homeowner
Explain system operation and maintenance procedures outlined in
User’s Manual.