Carrier 58MTB - Manual (Page 11)

11
2-5/32˝
(55 mm)
A04181
Fig. 14 -- Igniter
Step 7 — Electrical Controls and Wiring
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
There may be more than 1 electrical supply to the unit. Check
accessories and cooling unit for additional electrical supplies.
!
WARNING
The electrical ground and polarity for 115-v wiring must be
maintained properly. Refer to Fig. 15a or 15b for field wiring
information and to Fig. 21 for unit wiring information.
NOTE: If the polarity is not correct or the furnace is not
grounded, the STATUS LED on the furnace control board will
flash rapidly and prevent the furnace from operating. The control
system also requires an earth ground for proper operation of the
furnace control board and flame sensor.
The 24-v circuit contains an automotive-type, 3-amp fuse located
on the control. (See Fig. 16.) Any direct shorts of the 24-v wiring
during installation, service, or maintenance will cause this fuse to
blow. If fuse replacement is required, use ONLY a 3 amp fuse. The
control LED will display status code 24 when fuse needs to be
replaced.
With power to the unit disconnected, check all electrical
connections for tightness. Tighten all screws on electrical
connections. If any smoky or burned connections are found,
disassemble the connection, clean all parts, strip wire, and
reassemble properly and securely.
Reconnect electrical supply to unit and observe unit through 1
complete operating cycle for proper operation.
UNIT AND PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in furnace component
failures or water property damage.
If this furnace is to be operated in an unconditioned space
where the ambient temperatures may be 32_F (0_C) or lower,
freeze protection measures must be taken. (See Fig. 17). See
CONDENSATE DRAIN PROTECTION section of
Installation, Start--up, and Operating Instructions.
CAUTION
!
Step 8 — Checking Heat Tape Operation (If
Applicable)
In applications where the ambient temperature around the furnace
is 32°F
(0_C) or lower, freeze protection measures are required. If
this application is where heat tape has been applied, check to
ensure it will operate when low temperatures are present.
NOTE: Heat tape, when used, should be wrapped around the
condensate drain trap and drain line. There is no need to use heat
tape within the furnace casing. Most heat tapes are temperature
activated, and it is not practical to verity the actual heating of the
tape. Check the following:
1. Check for signs of physical damage to heat tape such as
nicks, cuts, abrasions, gnawing by animals, etc.
2. Check for discolored heat tape insulation. If any damage or
discolored insulation is evident, replace heat tape.
3. Check that heat tape power supply circuit is on.
Step 9 — Winterizing
UNIT DAMAGE HAZARD
Failure to follow this caution may result in furnace component
damage.
Freezing condensate left in the furnace may damage the
furnace.
CAUTION
!
If the furnace will be off for an extended period of time in a
structure where the temperature will drop to 32°F
(0_C)or below,
winterize as follows:
1. Turn off electrical supply to furnace.
2. Remove main furnace door.
3. Disconnect cap from unused drain tap on inducer housing.
(See Fig. 18.)
4. Connect field-supplied 1/2-in. I.D. tube to upper inducer
housing drain connection.
UNIT DAMAGE HAZARD
Failure of plastic components may occur.
Do not use ethylene glycol (Prestone II antifreeze/coolant or
equivalent automotive type).
CAUTION
!
58MTB