Fig. 12—field wiring – Carrier 58MCA User Manual

Page 8

Allow ignitor to cool before removal. Normal operation
temperatures exceed 2000°F.

a. Do not remove ignitor from retainer while assembly is in

furnace. Using a small pocket straight-blade screwdriver,
slowly pry 1 edge of the spring retainer from burner box
housing. While working ignitor assembly loose, grasp
white ceramic block to wiggle assembly (ignitor and
retainer) from its location.

The ignitor is fragile. DO NOT allow it to hit the side of the
burner box opening while removing or replacing it.

b. Inspect ignitor for a white area indicating a crack may be

present. If found, replace ignitor.

NOTE:

A small crack cannot be seen on a new ignitor. After a

period of operation, a white area will be visible around the crack.

c. If replacement is required, replace ignitor on ignitor re-

tainer external to furnace to avoid damage as the silicon
portion is very brittle and will easily crack or shatter.

d. To remove ignitor from ignitor retainer, apply pressure on

bottom/side clips to release pressure on ignitor ceramic
block. Slowly work ceramic block out of spring retainer.

6. To replace ignitor/ignitor assembly, reverse items 5a through

5d. (See Fig. 11.)

7. Reconnect ignitor wire connection.

8. Turn on gas and electrical supplies to furnace.

9. Verify ignitor operation by initiating control board self-test

feature or by cycling thermostat.

10. Replace main furnace door.

Step 7—Electrical Controls and Wiring

There may be more than 1 electrical supply to the unit. Check
accessories and cooling unit for additional electrical supplies.

The electrical ground and polarity for 115-v wiring must be
maintained properly. Refer to Fig. 12 for field wiring information
and to Fig. 16 for unit wiring information.

→

Fig. 12—Field Wiring

A96415

115-VOLT FUSED

DISCONNECT

SWITCH

(WHEN

REQUIRED)

AUXILIARY
J-BOX

CONTROL

BOX

24-VOLT

TERMINAL

BLOCK

THREE-WIRE

HEATING-

ONLY

FIVE

WIRE

NOTE 1

NOTE 2

FIELD-SUPPLIED
FUSED DISCONNECT

CONDENSING
UNIT

TWO
WIRE

FURNACE

GND

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

208/230- OR
460-VOLT
THREE
PHASE

208/230-
VOLT
SINGLE
PHASE

WHT

BLK

WHT

BLK

NOTES:

Connect Y-terminal as shown for proper operation.
Some thermostats require a "C" terminal connection as shown.
If any of the original wire, as supplied, must be replaced, use
same type or equivalent wire.

GND

THERMOSTAT
TERMINALS

1.
2.
3.

Fig. 11—Hot Surface Ignitor Location and Burner

Assembly

A93260

BURNER

IGNITOR

13 32

11 32

7 8

IGNITOR
ASSEMBLY

CELL
PANEL

BURNER

BURNER BOX