Carrier 58TMA User Manual

Page 6

18. Check for gas leaks.

19. Replace control door.

Never use a match or other open flame to check for gas leaks.
Use a soap-and-water solution. A failure to follow this
warning could result in fire, personal injury, or death.

ELECTRICAL CONTROLS AND WIRING

NOTE:

There may be more than 1 electrical supply to unit.

The electrical ground and polarity for 115-v wiring must be
maintained properly. Refer to Fig. 10 and 11 for field wiring
information and to Fig. 12 for unit wiring information. If the

polarity is NOT correct, the furnace control will display code 02 on
the status LED and prevent heat operation. The control system also
requires an earth ground for proper operation of the microproces-
sor.

With power disconnected to unit, check all electrical connections
for tightness. Tighten all screws on electrical connections. If any
smoky or burned connections are noticed, disassemble the connec-
tion, clean all parts and stripped wire, and reassemble properly and
securely. Electrical controls are difficult to check without proper
instrumentation; therefore, reconnect electrical power to unit and
observe unit through 1 complete operating cycle.

The 24-v circuit contains an automotive-type, 3-amp fuse located
on the main control. Any 24-v electrical shorts during installation,
service, or maintenance could cause this fuse to blow. If fuse

Fig. 10—Heating and Cooling Application Wiring Diagram

A93378

115-VOLT FIELD-

SUPPLIED

FUSED

DISCONNECT

JUNCTION
BOX

CONTROL

BOX

24-VOLT

TERMINAL

BLOCK

TWO-WIRE

HEATING-

ONLY

FOUR

WIRE

1-STAGE
THERMOSTAT
TERMINALS

FIELD-SUPPLIED

FUSED DISCONNECT

CONDENSING

UNIT

FURNACE

COM

GND

FIELD 24-VOLT WIRING
FIELD 115-, 208/230-, 460-VOLT WIRING
FACTORY 24-VOLT WIRING
FACTORY 115-VOLT WIRING

NOTE: Connect Y-terminal as
shown for proper
operation.

NOTE: If any of the original wire,
as supplied, must be replaced, use
same type or equivalent wire.

208/230- OR
460-VOLT
THREE
PHASE

208/230-
VOLT
SINGLE
PHASE

WHT

BLK

WHT

BLK

W/W1

Y/Y2

Fig. 11—Heating and Cooling Application Wiring Diagram for 2-Stage Thermostats and/or 2-Speed

Condensing Units

A93379