24-V Wiring; Accessories; Direct Venting; Removal Of Existing Furnaces From Common Vent Systems - Carrier 58MXA Nstallation, Start-Up, And Operating Instructions

VOLTS—
UNIT
HERTZ—
SIZE
PHASE
040-08 115-60-1
040-12 115-60-1
060-08 115-60-1
060-12 115-60-1
060-16 115-60-1
080-12 115-60-1
080-16 115-60-1
080-20 115-60-1
100-16 115-60-1
100-20 115-60-1
120-20 115-60-1
140-20 115-60-1
* Permissible limits of voltage range at which unit will operate satisfactorily.
† Unit ampacity = 125 percent of largest operating component's full load amps plus 100 percent of all other potential operating components' (EAC, humidifier, etc.) full
load amps.
‡ Length shown is a measured 1 way along wire path between unit and service panel for maximum 2 percent voltage drop.
** Time-delay type is recommended.
Do not connect aluminum wire between disconnect switch
and furnace. Use only copper wire. (See Fig. 28.)
The cabinet MUST have an uninterrupted or unbroken ground
according to NEC ANSI/NFPA 70-1999 and Canadian Elec-
trical Code CSA C22.1 or local codes to minimize personal
injury if an electrical fault should occur. This may consist of
electrical wire or conduit approved for electrical ground when
installed in accordance with existing electrical codes. Do not
use gas piping as an electrical ground. Failure to follow this
warning could result in electrical shock, fire, or death.
J-Box Relocation
1. Remove 2 screws holding auxiliary J-box. (See Fig. 29.)
2. Rotate J-box 180° and attach box to left side, using holes
provided.
ALTERNATE
FIELD
LOCATION
Fig. 29—Relocating J-Box
Table 4—Electrical Data
OPERATING
MAX
VOLTAGE RANGE
UNIT
AMPS
Max* Min*
127 104
127 104
127 104
127 104
127 104
127 104
127 104 10.0
127 104 14.1
127 104 10.2
127 104 14.8
127 104 14.6
127 104 14.3
FACTORY
INSTALLED
LOCATION
A00212
UNIT
AMPACITY†
6.1 8.4
7.3 10.0
6.1 8.4
7.1 9.8
9.5 12.8
7.6 10.4
13.4
18.4
13.5
19.3
19.1
18.8
If manual disconnect switch is to be mounted on furnace,
select a location where a drill or fastener will not contact
electrical or gas components.
24–V WIRING
Make field 24-v thermostat connections at 24-v terminal block on
control center. For proper cooling operation, Y wire from thermo-
stat MUST be connected to Y terminal on control center, as shown
in Fig. 27. The 24-v terminal board is marked for easy connection
of field wiring. (See Fig. 30.) The 24-v circuit contains a 3-amp,
automotive-type fuse located on control center. (See Fig. 31.) Any
electrical shorts of 24-v wiring during installation, service, or
maintenance may cause fuse to blow. If fuse replacement is
required, use only a fuse of identical size (3 amp).
NOTE: Use AWG No. 18 color-coded copper thermostat wire
for lengths up to 100 ft. For wire lengths over 100 ft, use AWG No.
16 wire.

ACCESSORIES

1. Electronic Air Cleaner (EAC)
Two quick-connect terminals marked EAC-1 and EAC-2 are
provided for EAC connection. (See Fig. 31.) These terminals
are energized with 115-v (1.5-amp maximum) during blower
motor operation.
2. Humidifier (HUM)
A quick-connect terminal (HUM) and screw terminal (C
are provided for 24-v humidifier connection. (See Fig. 30.)
HUM terminal is energized with 24-v (0.5-amp maximum)
after inducer pressure switch closes.
NOTE: A field-supplied, 115-v controlled relay connected to
EAC terminals may be added if humidifier operation is desired
during blower operation.
Step 9—Direct Venting
The 58MXA furnaces require a dedicated (one 58MXA furnace
only) direct-vent system. In a direct-vent system, all air for
combustion is taken directly from outside atmosphere, and all flue
products are discharged to outside atmosphere.
REMOVAL OF EXISTING FURNACES FROM COMMON
VENT SYSTEMS
If furnace being replaced was connected to a common vent system
with other appliances, the following steps shall be followed with
20
MIN MAX WIRE
WIRE LENGTH
SIZE (FT)‡
14 44
14 37
14 44
14 38
14 29
14 36
14 28
12 31
14 27
12 30
12 30
12 30
MAX FUSE
OR CKT BKR
AMPS**
15
15
15
15
15
15
15
20
15
20
20
20
)
OM