KeepRite F9MAC Series, Service And Technical Support Manual

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SERVICE AND TECHNICAL SUPPORT MANUAL Gas Furnace: (F/G)9MAC
Specifications subject to change without notice.
440 04 4201 03 21
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 service and maintenance on
this equipment requires certain knowledge, mechanical skills,
tools, and equipment. If you do not possess these, do not
attempt to perform any service and maintenance on this
equipment other than those procedures recommended in the
User’s Manual.
!
CAUTION
ENVIRONMENTAL HAZARD
Failure to follow this caution may result in environmental
pollution.
Remove and recycle all components or materials (i.e. oil,
refrigerant, control board, etc.) before unit final disposal.
!
WARNING
ELECTRICAL SHOCK, FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal injury or
death, or property damage.
Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position and
install a lockout tag. There may be more than one
disconnect switch. Lock out and tag switch with a suitable
warning label. 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 four positions shown
in Figure 6 , you must revise your orientation to component
location accordingly.
Figure 6 Multipoise Orientations
A93041
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. Lock
out and tag switch with a suitable warning label.
The electrical ground and polarity for 115 − v wiring must be
properly maintained. Refer to Figure 7 for field wiring
information and to Figure 15 for furnace wiring information.
NOTE : If the polarity is not correct, the STATUS LED on the
control will flash code 10 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 Figure 3 ) 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 display will be off when fuse
needs replacing.
Troubleshooting
Refer to the service label. (See Figure 14 —Service Label)
The Troubleshooting Chart − Flow Chart (See Figure 16 ) can
be a useful tool in isolating furnace operation problems.
Beginning with the word “Start,” answer each question and
follow the appropriate arrow to the next item.
The Chart
− Flow Chart will help to identify the problem or failed
component. After replacing any component, verify correct
operation sequence.
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. Status codes can be viewed at the sight glass
in blower access door. The amber furnace control LED is either
heartbeat, off or a code composed of 1 or 2 digits. The first digit
is the number of short flashes, the second digit is the number of
long flashes.