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440 01 2020 01
NOTE:
To further reduce noise, install acoustical air turning vanes
and/or line the inside of duct with acoustical material.
Sizing
Existing or new ductwork
MUST
be sized to handle the correct
amount of airflow for either heating only or heating and air condi-
tioning.
Insulation
1. Insulate ductwork installed in attics or other areas exposed
to outside temperatures with a minimum of 2
²
insulation and
vapor barrier.
2. Insulate ductwork in indoor unconditioned areas with a mini-
mum of 1
²
insulation with indoor type vapor barrier.
Filters
A Filter
must
be used:
Filters are not supplied with these furnaces, but can be purchased
from dealer.
Use either filter type:
·
Washable, high velocity filters are based on a maximum
air flow rating of 600 FPM.
·
Disposable, low velocity filters are based on a maximum
air flow of 300 FPM when used with filter grille.
NOTE:
Disposable, low velocity filters may be replaced with wash-
able, high velocity filter providing they meet the minimum size
areas. Washable, high velocity filters can be replaced
ONLY
with
same type and size.
Figure 34
Side Mounted Filter Rack
25--20--90
Filter Installation using Filter Rack
When installing or removing a bottom mounted filter, slide the two
side filter clips to the back of the furnace
BEFORE
installing or re-
moving. This will allow the filter to clear the front raised edge of the
furnace. Insert filter into side clips first and push filter back until it is
fully engaged into back clip. When filter is in place, slide clips back
into place midway on filter as shown in
Figure 35.
Figure 35
Bottom Mounted Filter Rack
Slide filter clips towards back before removing
25--24--18
Refer to
Figure 36
and for guidelines to install filters. Furnaces
which require larger filter media and have limited clearances on
one side of furnace, require a standoff filter rack, see
Figure 36
,
available from your distributor.
Figure 36
Standoff Filter Rack
25--21--45a
Using Optional
Standoff Filter
Rack
CAUTION
If filters are only suitable for heating application, advise
homeowner that filter size may need to be increased if air
conditioning is added.
Addition Of Air Conditioning
When a refrigeration coil is used in conjunction with this unit, it must
be installed on the discharge side of the unit to avoid condensation
on the heat exchanger. The coil installation instructions must be
consulted for proper coil location and installation procedures. With
a parallel flow arrangement, dampers must be installed to prevent
chilled air from entering the furnace. If manually operated dampers
are used, they must be equipped with a means to prevent operation
of either unit unless the damper is in full heat or full cool position.
A 3
²
clearance is required on the right side of the furnace in order to
run the condensate drain line. Copper, iron or plastic tubing may be
used for the condensate drain line.
Summary of Contents for 9MPT050F12A
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