269436-UIM-A-0407
6
Unitary Products Group
RESIDENTIAL AND NON HUD MODULAR HOME
RETURN PLENUM CONNECTION
Return air may enter the furnace through the side(s) or bottom depend-
ing on the type of application. Return air may not be connected into the
rear panel of the unit. In order to stay within the velocity rating of the fil-
ter(s), it is recommended that applications over 1800 CFM (51 m³/min)
use return air from two sides, one side and the bottom or bottom only.
For single return application, see data and notes on blower perfor-
mance data tables in this manual.
BOTTOM RETURN AND ATTIC INSTALLATIONS
Bottom return applications normally pull return air through a base plat-
form or return air plenum. Be sure the return platform structure or return
air plenum is suitable to support the weight of the furnace.
The furnace base is equipped with a rectangular blockoff panel that can
be removed by performing the following steps:
1.
Lay the furnace on its back.
2.
Remove the screws from the toe plate.
3.
Remove the toe plate.
4.
Pull the base plate out of the furnace base.
5.
Reinstall the toe plate and secure with the screws that were
removed.
Attic installations must meet all minimum clearances to combustibles
and have floor support with required service accessibility.
IMPORTANT:
If an external mounted filter rack is being used see the
instructions provided with that accessory for proper hole cut size.
SECTION III: FILTERS
FILTER INSTALLATION
All applications require the use of a filter.
Filters must be installed external to the furnace cabinet.
DO NOT
attempt to install filters inside the furnace.
FIGURE 1:
Dimensions
13-7/8
7/8
23-3/4
7/8
30-1/8
1-1/2” GAS
PIPE ENTRY
7/8” JUNCTION
BOX HOLE
T-STAT WIRING
7/8” K.O.
CONDENSATE
DRAIN 7/8” K.O.
OPTIONAL RETURN AIR
CUT-OUT (either side)
FOR USE WITH
EXTERNAL FILTER
FRAME
LEFT SIDE
RIGHT SIDE
26-3/4
1-1/2
1-1/4
C
24-3/8
20
5/8
5/8
B
24-17/16
2
D
BOTTOM IMAGE
RETURN END
TOP IMAGE
SUPPLY END
1-1/2” GAS
PIPE ENTRY
7/8” JUNCTION
BOX HOLE
T-STAT WIRING
7/8” K.O.
CONDENSATE
DRAIN 7/8” K.O.
A
40
FRONT
BTUH (kW)
Input/Output
CFM
(m
3
/min)
Cabinet
Size
Cabinet Dimension
A (in.)
A (cm)
B (in.)
B (cm)
C (in.)
C (cm)
D (in.)
D (cm)
40 (11.7)
1200 (34.0)
A
14-1/2
36.8
13-1/4
33.7
11-1/2
29.2
6-1/4
15.9
60 (17.8)
1200 (34.0)
B
17-1/2
44.4
16-1/4
41.3
14-1/2
36.8
8-1/2
21.6
80 (12.4)
1200 (34.0)
B
17-1/2
44.4
16-1/4
41.3
14-1/2
36.8
8-1/2
21.6
80 (23.4)
1600 (45.3)
C
21
53.3
19-3/4
50.2
18
45.7
8-7/8
22.5
80 (23.4)
2000 (56.6)
C
21
53.3
19-3/4
50.2
18
45.7
8-7/8
22.5
100 (29.3)
1600 (45.3)
C
21
53.3
19-3/4
50.2
18
45.7
8-7/8
22.5
100 (29.3)
2000 (56.6)
C
21
53.3
19-3/4
50.2
18
45.7
8-7/8
22.5
120 (35.1)
2000 (56.6)
D
24-1/2
62.2
23-1/4
59.4
21-1/2
54.6
10-5/8
27.0
135 (39.6)
2000 (56.6)
D
24-1/2
62.2
23-1/4
59.4
21-1/2
54.6
10-5/8
27.0
