035-17477-001 Rev. A (801)
Unitary Products Group
35
HORIZONTAL APPLICATIONS
In most horizontal applications the filter is located in the
return air duct near the furnace or in a filter grille.
LUBRICATION
Blower motors in these furnaces are permanently lubricated
and do not require periodic oiling.
BLOWER CARE
Even with good filters properly in place, blower wheels and
motors will become dust laden after long months of operation.
The entire blower assembly should be inspected annually. If
the motor and wheel are heavily coated with dust, they can
be brushed and cleaned with a vacuum cleaner.
The procedure for removing the direct drive blower assembly
for cleaning is as follows:
1.
Disconnect the electrical supply to the furnace and
remove remove the access doors.
2.
On downflow/horizontal models only, remove the two
wires leading to the auxiliary limit mounted on the blower
housing.
3.
On downflow/horizontal models only, remove four top
panel screws and lift the top panel enough to disengage
and remove the flue chase assembly.
4.
Remove blower assembly mounting screws and slide the
blower assembly out of the slots in the deck. If the two
shipping screws were not previously removed, also
remove and discard these two screws located on each
front corner of the blower assembly.
5.
On downflow models only, note the wire/terminal location
and then remove the blower wiring from the furnace con-
trol. Remove the protective boot and disconnect run
capacitor wires. Remove the screws securing the electri-
cal panel to the blower housing. Pull blower assembly
out of the unit. When cleaning or servicing the blower
assembly, DO NOT remove or change the balance clips
on the blower wheel.
6.
To reassemble, reverse the procedure, restore power to
the furnace and verify operation.
When replacing filters, DO NOT use a type with
excessively high pressure drop. Some high
efficiency filters available will cause the furnace to
operate improperly and could result in a safety
hazard.
FIGURE 42 :
Furnace Control Event Schedule
