15
441 01 5001 00
Inspection Panel on some models
A removal access panel should be provided in the outlet duct
when the furnace is installed without a cooling coil. This will allow
smoke or reflected light to be observable inside the casing to indi-
cate the presence of leaks in the heat exchanger. This access cov-
er shall be attached in such a manner as to prevent air leaks.
Filters
A filter MUST be used:
Filters are not supplied with these furnaces, but can be purchased
from your 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.
·
The furnaces, with 1600 or less CFM rating use a 16
²
x 25
²
high velocity filter. On these models the filter may be
mounted internally for bottom return using factory kit or ex-
ternally for side return.
·
The furnaces with greater than 1600 CFM requires that both
left and right side returns are used in side return applica-
tions. Two 16
²
x 25
²
high velocity filters and racks are pro-
vided with furnace. Filter racks must be mounted externally.
If return air must be on one side only, an optional 20
²
x 25
²
filter standoff rack kits can be used. (See
Figure 12)
For
bottom return, an optional 20
²
x 25
²
filter rack kit can be
mounted internally.
NOTE:
The 20 x 25
²
standoff filter rack gives more filter area but
does not provide more air. To achieve 2000 CFM a bottom return
or 2 side returns are still needed.
NOTE:
Disposable, low velocity filters may be replaced with
washable, high velocity filter providing they meet the minimum
size areas. Washable, high velocity filters can be replaced
ONLY
with same type and size.
25-20-31
Figure 12
Optional Duct Standoff
20 x 25 Optional
Filter Rack
Filter Installation using Optional 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 13.
Figure 13
Bottom Mounted Filter Rack
Slide filter clips towards back before removing
25--24--18
9. Checks and Adjustments
Startup
NOTE:
Refer to startup procedures in the
Users Information
Manual
.
CAUTION
If any sparks, odors or unusual noises occur, immedi-
ately shut OFF power to furnace. Check for wiring er-
rors or obstruction to blower.
Gas Supply Pressure
Gas supply pressure should be within minimum and maximum
values listed on rating plate. Pressures are usually set by gas sup-
pliers.
(See L.P. Kit instruction manual for furnaces converted to L.P. gas)
Manifold Gas Pressure Adjustment
NOTE:
Make adjustment to manifold pressure with burners oper-
ating.
!
Fire or explosion hazard.
Turn OFF gas at shut off before connecting
manometer.
Failure to turn OFF gas at shut off before
connecting manometer can result in death and/or
personal injury.
1. With gas
OFF
, Connect manometer to gas valve or maniflod
tap. Use manometer with a 0 to min. 12
²
water column range.
2. Turn gas
ON
and remove adjustment screw cover on gas
valve. Turn counterclockwise to decrease pressure and
clockwise to increase.
