NOTE: Some electronic thermostats also have a
HIGH PRESSURE SWITCH/LOSS OF CHARGE SWITCH
Some models include a high pressure cutout switch and/or a loss of charge cutout switch. The high pressure cutout switch protects the refrigeration system from excessive operating pressures. The loss of charge cutout switch protects 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
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 combustion 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 location of the return air filter(s) for your unit.
Dirty filters are the most common cause of inadequate heating 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 uncleanable, 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 sunlight.
CLEAN OUTSIDE COIL (QUALIFIED SERVICER ONLY)
The coil with the outside air flowing over it should be inspected 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 motor and the combustion fan motor are permanently lubricated. No additional oiling is required.
FLAME SENSOR (QUALIFIED SERVICER ONLY)
A drop in the flame current can be caused by a nearly invisible 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 necessary, 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”.
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