29733 R2 06/01/2003
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THE BELT DRIVE COMPONENTS OPERATE AT
HIGH SPEEDS AND CAN EASILY SNAG LOOSE
CLOTHING, CAUSING SERIOUS PERSONAL
INJURY. THIS PROCEDURE SHOULD BE LEFT TO
TRAINED SERVICE PERSONNEL.
If the blower RPM operates above 1000 RPM, it is
advisable to replace the sintered bronze blower bearings
with roller Bearings.
The circulating fan start-up is delayed 30 or 45 seconds
(depending on EFT) in the heating mode.
The circulating fan start-up is delayed 30 seconds in the
cooling mode. The “fan off” is delayed 30 seconds in the
cooling mode.
The “fan off” delay may be field adjusted by manipulating
the dipswitches. See Figures 8.
Figure 8: Heating Mode “Blower Off” Timings, ST9103
DISCONNECT THE POWER SUPPLY TO THE
FURNACE BEFORE OPENING THE BLOWER
ACCESS DOOR TO SERVICE THE AIR FILTER, FAN
AND MOTOR. FAILURE TO SHUT OFF POWER
COULD ALLOW THE BLOWER TO START
UNEXPECTEDLY, CREATING A RISK OF DEATH
OR PERSONAL INJURY.
Do not use the blower speed wires as a source of
power to accessories as electronic air cleaners and
humidifier transformers. The unused motor taps
auto-generate sufficiently high voltages to damage
accessory equipment. Use the terminals provided on
the ST9103 EFT
DO NOT START THE BURNER OR BLOWER FAN
UNLESS THE BLOWER ACCESS DOOR IS
SECURELY IN PLACE.
Additional ST9103 Fan Timer Control information is in
Appendix A, Tables, and in Appendix B, Wiring
Diagrams.
A: Routine Maintenance By Home Owner
Other than remembering to arrange for the annual
professional servicing of the furnace by the service or
installation contractor, the most important routine service
performed by the homeowner is to maintain the air filter
or filters. A dirty filter can cause the furnace to over-heat,
fail to maintain indoor temperature during cold weather,
increase fuel consumption and cause component failure.
The furnace filter(s) should be inspected, cleaned or
replaced monthly. The furnace is factory equipped with a
semi-permanent type filter. If the filter is damaged,
replace with filters of the same size and type.
During the routine service, inspect the general condition
of the furnace watching for signs of oil leaks in the vicinity
of the oil burner, soot forming on any external part of the
furnace, soot forming around the joints in the vent pipe,
etc. If any of these conditions are present, please advice
your service or installation contractor.