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the refrigeration system from very low operating pressures
due to a loss of refrigerant. Compressor operation will be
disabled if either of these devices opens. If either devices
opens, the diagnostic red LED will flash (9) times to indicate
that a refrigeration system pressure switch is open.
MAINTENANCE
WARNING
High Voltage!
Disconnect ALL power before servicing or
installing thus unit. Multiple power sources may
be present. Failure to do so may cause property
damage, personal injury, or death.
Have the gas heating section of the unit checked at least
once a year before the heating season begins, to be sure
that the combustion air inlet and flue outlet hoods are not
blocked by debris, which would prevent adequate combus-
tion air and a properly operating vent system.
Filter Replacement or Cleaning
A return air filter is not supplied with this unit; however, there
must be a means of filtering all of the return air. The filter(s)
may be located in the return air duct(s), or return air filter
grille(s). Consult with your installing dealer for the actual lo-
cation of the return air filter(s) for your unit.
Dirty filters are the most common cause of inadequate heat
-
ing or cooling performance. Filter inspection should be made
at least every two months; more often if necessary because
of local conditions and usage.
Dirty throwaway filters should be discarded and replaced
with a new, clean filter. Dirty permanent filters should be
washed with water, thoroughly dried and sprayed with a filter
adhesive before being reinstalled. (Filter adhesives may be
found at many hardware stores.) Permanent filters should
last several years. However, should one become torn or un
-
cleanable, it should be replaced.
Cabinet Finish Maintenance
Use a fine grade automotive wax on the cabinet finish to
maintain the finish’s original high luster. This is especially
important in installations with extended periods of direct sun-
light.
Clean Outside Coil (Qualified Servicer Only)
The coil with the outside air flowing over it should be inspect
-
ed annually and cleaned as frequently as necessary to keep
the finned areas free of lint, hair and debris.
Condenser, Evaporator, and Induced Draft Motors
Bearings on the air circulating blower motor, condenser mo-
tor and the combustion fan motor are permanently lubricat-
ed. No additional oiling is required.
Flame Sensor (Qualified Servicer Only)
A drop in the flame current can be caused by a nearly invisi
-
ble coating on the flame sensor. This coating, created by the
fuel or combustion air supply, can be removed by carefully
cleaning the flame sensor with steel wool.
NOTE:
After cleaning, the microamp signal should be stable
and in the range of 4 - 6 microamps DC.
Flame
Sensor
Flame Sensor
Flue Passages (Qualified Servicer Only)
At the start of each heating season, inspect and, if neces-
sary, clean the unit flue passage.
Cleaning Flue Passages (Qualified Servicer Only)
1. Shut off electric power and gas supply to the unit.
2. Remove burner assembly by disconnecting the gas
line and removing the manifold bracket from the
partition panel.
3. Remove the flue from the induced draft blower and
the collector box cover from the partition panel.
4. The primary heat exchanger tubes can be cleaned
using a round wire brush attached to a length of high
grade stainless steel cable, such as drain cleanout
cable. Attach a variable speed reversible drill to the
other end of the spring cable. Slowly rotate the cable
with the drill and insert it into one of the primary heat
exchanger tubes. While reversing the drill, work the
cable in and out several times to obtain sufficient
cleaning. Use a large cable for the large tube, and
then repeat the operation with a small cable for the
smaller tube. Repeat for each tube.
5. When all heat exchanger tubes have been cleaned,
replace the parts in the reverse order in which they
were removed.
6. To reduce the chances of repeated fouling of the
heat exchanger, perform the steps listed in “Startup,
Adjustments, and Checks”.
Main Burner Flame (Qualified Servicer Only)
Flames should be stable, soft and blue (dust may cause or-
ange tips but must not be yellow). The flames must extend
directly outward from the burner without curling, floating or
lifting off.
At least once a year, prior to or during the heating season,
make a visual check of the burner flames.
