035-17480-000 Rev. A (800)
Unitary Products Group
29
MAINTENANCE
Air Filters
The filters must be checked periodically for dirt accumulation.
Dirty filters greatly restrict the flow of air and may cause dam-
age to the system.
Clean the filters at least every three months. On new con-
struction, check the filters every week for the first four weeks.
Inspect the filters every three weeks after that, especially if
the system is running constantly.
All filters used with the furnace are the high-velocity, clean-
able type. Clean these filters by washing in warm water.
Make sure to shake all the water out of the filter and have it
reasonably dry before installing it in the furnace. When
replacing filters, be sure to use the same size and type as
originally supplied.
Filter Removal - Upflow Models
The ends of the retainer are attached to the rear panel in two
metal loops. (Refer to Figure 30.) The ends must be
squeezed together to free them from the loops. The retainer
may then be moved to the new location and the ends inserted
in the loops on the rear panel at the new location. Loops are
provided for retainer location to accommodate filter applica-
tion on the bottom or either side of the furnace.
To remove a filter from the bottom location, push the closed
end of the filter retainer to the left until it clears the lip on the
front of the furnace base, which acts as a catch for the
retainer. When the retainer is clear of the flange, it will pivot in
the loops.
Swing the retainer toward the center of the furnace. This will
expose the filter to allow removal. To reinstall the filter, simply
reverse this procedure.
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 opera-
tion. The entire blower assembly should be inspected annu-
ally. 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 the access doors.
2.
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.
3.
To reassemble, reverse the procedure, restore power to
the furnace and verify operation.
Burner Removal/Cleaning
The main burners should be checked periodically for dirt
accumulation.
If cleaning is required, follow this procedure:
1.
Turn off the electrical power to the unit.
2.
Turn off the gas supply at the external manual shutoff
valve and loosen the ground union joint.
3.
Remove the upper access panel and remove the burner
box cover.
4.
Remove the screws that hold the burner box assembly to
the vest panel and remove the assembly.
5.
Remove burners from the burner assembly.
6.
Burners may be cleaned by rinsing in hot water.
7.
Reassemble the burners in the reverse order.
Cleaning the Heat Exchanger
1.
Turn off the main manual gas valve external to the fur-
nace.
2.
Turn off electrical power to the furnace.
3.
Remove the upper access panel and remove the burner
box cover.
FIGURE 30 :
Upflow Filter Retainer
