Checklist; Service And Maintenance Procedures; General - Carrier 140/E Series Installation, Start-Up, Operating And Service And Maintenance Instructions

safeguard switch did not function properly and correct
condition.
f. Remove blockage from furnace vent elbow.
g. Switch will auto- -reset when it cools.
h. Re- -install vent connector.
NOTE: Should switch remain open longer than 3 minutes,
furnace control board will lockout the furnace for 3 hours. To
reset furnace control board, turn thermostat below room
temperature or from HEAT to OFF and turn 115- -v power OFF,
then back ON.
3. Check Pressure Switch(es)
This control proves operation of the draft inducer blower.
a. Turn off 115- -v power to furnace.
b. Disconnect inducer motor lead wires from wire har-
ness.
c. Turn on 115- -v power to furnace.
d. Set thermostat to "call for heat" and wait 1 minute.
When pressure switch is functioning properly, hot sur-
face igniter should NOT glow and control diagnostic
light flashes a status code 32. If hot surface igniter
glows when inducer motor is disconnected, shut down
furnace immediately.
e. Determine reason pressure switch did not function
properly and correct condition.
f. Turn off 115- -v power to furnace.
g. Reconnect inducer motor wires, replace outer door,
and turn on 115- -v power.
h. Blower will run for 90 seconds before beginning the
call for heat again.
i. Furnace should ignite normally.

Checklist

1. Put away tools and instruments. Clean up debris.
2. Verify that switches SW1- -1 and SW1- -6 are OFF and oth-
er setup switches are set as desired. Verify that switches
SW1- -7 and SW1- -8 for the blower OFF DELAY are set as
desired per Table 8.
3. Verify that blower and burner access doors are properly in-
stalled.
4. Cycle test furnace with room thermostat.
5. Check operation of accessories per manufacturer's instruc-
tions.
6. Review User's Guide with owner.
7. Attach literature packet to furnace.
SERVICE AND MAINTENANCE
PROCEDURES
WARNING
!
FIRE, INJURY OR DEATH HAZARD
Failure to follow this warning could result in personal
injury, death and/or property damage.
The ability to properly perform maintenance on this
equipment requires certain knowledge, mechanical skills,
tools, and equipment. If you do not possess these, do not
attempt to perform any maintenance on this equipment
other than those procedures recommended in the User's
Manual.
WARNING
!
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow this warning could result in personal
injury or death, or property damage.
Before servicing, disconnect all electrical power to furnace.
Verify proper operation after servicing.
CAUTION
!
ELECTRICAL OPERATION HAZARD
Failure to follow this caution may result in improper
furnace operation or failure of furnace.
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and dangerous
operation.

General

These instructions are written as if the furnace is installed in an
upflow application. An upflow furnace application is where the
blower is located below the combustion and controls section of
the furnace, and conditioned air is discharged upward. Since this
furnace can be installed in any of the 4 positions shown in Fig. 4,
you must revise your orientation to component location
accordingly.
Electrical Controls and Wiring
WARNING
!
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
There may be more than one electrical supply to the furnace.
Check accessories and cooling unit for additional electrical
supplies that must be shut off during furnace servicing.
The electrical ground and polarity for 115- -v wiring must be
properly maintained. Refer to Fig. 26 for field wiring information
and to Fig. 59 for furnace wiring information.
NOTE: If the polarity is not correct, the STATUS LED on the
control will flash rapidly and prevent the furnace from heating.
The control system also requires an earth ground for proper
operation of the control and flame- -sensing electrode.
The 24- -v circuit contains an automotive- -type, 3- -amp. fuse
located on the control. (See Fig. 27.) Any 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.
Proper instrumentation is required to service electrical controls.
The control in this furnace is equipped with a Status Code LED
(Light- -Emitting Diode) to aid in installation, servicing, and
troubleshooting. It can be viewed through the sight glass in
blower access door. The amber furnace control LED is either ON
continuously, rapid flashing, or a code composed of 2 digits. The
first digit is the number of short flashes, the second digit is the
number of long flashes.
For an explanation of status codes, refer to service label located
on blower access door or Fig. 58, and the troubleshooting guide
which can be obtained from your distributor.
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