9
Side Air Return
1. Lift filter above bottom
2. Tilt filter to clear rail.
rail.
Front of Furnace
Blower
Grab Here
And Lift
Fi
lt
e
r
Front of Furnace
Blower
3. Lower filter below top
4. Pull filter out.
rail.
Front of Furnace
Blower
Front of Furnace
Blower
Figure 8
Filter Removal
Side Return Filter Sizes
Minim um Recom m ended Size, Inches
Size_Air Flow
Disposable*
Perm anent*
045_30
1 - 24x24 (576)
1 - 16x25 (280)
070_30
1 - 24x24 (576)
1 - 16x25 (280)
070_40
2 - 16x25 (768)
1 - 16x25 (372)
090_35
2 - 14x25 (692)
1 - 16x25 (342)
090_50
2 - 20x25 (960)
2 - 16x25 (465)
115_50
2 - 20x25 (960)
2 - 16x25 (465)
*
Quantity - Inches (Total Minimum Surface Area in Square Inches)
Permanent filter sizes are as shipped with furnace. The minimum
permanent filter size area is based on allowable face velocity of 620
feet per minute.
Table 2
Bottom Air Return
The filter is held in place by a sheet metal retainer strap
(Figure 9). To change and clean the filter, slide one end of the
retainer towards the front and remove filter.
Figure 9
Filter Retainer
Bottom Return Filter Sizes
Model
Filter Size, Inches Type
45
14 x 25 x 1
P
70
16 x 25 x 1*
P
90
20 x 25 x 1
P
115
20 x 25 x 1
P
P = Permanent
* As Shipped With Furnace
Table 3
Filter Cleaning and Replacing
Use a vacuum cleaner to clean out the blower area and the
adjacent area of the return air duct.
Wash, rinse, and dry a permanent filter. Both sides of a metal
filter should be sprayed with a dust adhesive as recom-
mended on the adhesive container. Spray adhesives for use
with permanent metal filters can be found at some hardware
stores.
If permanent filter are badly torn or uncleanable, they must be
replaced with permanent filters of the same type and size.
When replacing permanent filter used in side air return
applications must have dimensions of 16" x 25" x 1".
When replacing permanent filter used in bottom air return
applications use the Table 2 or 3 to determine filter size.
Reinstall filter by placing it into the furnace along the side of
the blower. Engage filter in top rail, move toward side of
furnace and drop it into the bottom rail. BE SURE AIRFLOW
DIRECTION ARROW POINTS TOWARDS THE BLOWER.
Condensate Collection and Disposal (Qualified
Servicer Only)
If the drain tubes or condensate collection standpipe assem-
bly become blocked, the components may be removed,
cleaned and reinstalled.
Induced Draft Motor Lubrication
The induced draft motor bearings are permanently lubri-
cated. No further lubrication is required.
Air Circulating Blower Motor Lubrication
The air circulation blower motor bearings are permanently
lubricated. No further lubrication is required.
