TOP VIEW
SUPPLY
AIR
OPENING
SIDE VIEW
DOWN-FLOW
ADDITIVE
FLOOR BASE
DOWN
FLOW
FURNACE
A
B
27-1/4
(692)
19-13/16
(503)
1-1/2
(38)
21-13/16
(554)
FLOOR
OPENING
1-1/2
(38)
1-1/2
(38)
1-1/2
(38)
Front Of Furnace
22
(559)
C
DOWN-FLOW ADDITIVE FLOOR BASE
G61MPV / Page 12
OPTIONAL ACCESSORY DIMENSIONS − INCHES (MM)
1
Both the unit return air opening and the base return air opening must be covered by a single plenum or IAQ cabinet.
Minimum unit side return air opening dimensions for units requiring 1800 cfm or more of air (W x H): 23 x 11 in. (584 x 279 mm).
The opening can be cut as needed to accommodate plenum or IAQ cabinet while maintaining dimensions shown.
Side return air openings must be cut in the field. There are cutting guides stenciled on the cabinet for the side return air
opening. The size of the opening must not extend beyond the markings on the furnace cabinet.
2
14 inches (356 mm) is the maximum size the height of the unit opening can be cut. This may interfere with the condensate drain
(if located on the same side of the unit as the opening).
To minimize pressure drop, the largest opening height possible (up to 14 inches) is preferred.
NOTE− Optional Side Return Air Filter Kits are not for use with RAB Return Air Base.
RAB RETURN AIR BASE (Up−Flow Applications Only)
For use with B, C, and D size furnaces only
1
Unit side return
air Opening
SIDE VIEW
27−5/8 (702)
4
(102)
1
23 (584)
Overall
(Maximum)
1
Minimum
11 (279)
2
Maximum
14 (356)
OPTIONAL RAB
RETURN AIR BASE
23 (584)
7−1/4 (184)
7/8
(22)
3/4
(19)
1
20−1/2
(521)
Overall
(Maximum)
SIDE RETURN
AIR OPENINGS
(Either Side)
FURNACE
FRONT
14
(356)
14
(356)
CONDENSATE
TRAP
4
(102)
FRONT VIEW
21 (533) RAB−C (98M58)
24−1/2 (622) RAB−D (98M59)
17−1/2 (446) RAB−B (98M60)
5−5/8
(143)
AIR FLOW
A B C
o
e
o.
in.
mm in. mm in. mm
G61MPV−36B−045
G61MPV−36B−070
G61MPV−36B−071
19−9/16 497 16−9/16 421 18−3/4 476
G61MPV−36C−090
G61MPV−60C−090
G61MPV−60C−091
G61MPV−60C−110
G61MPV−60C−111
23−1/16 586 20−1/16 510 22−1/4 565
G61MPV−60D−135 26−9/16 675 23−9/16 598 25−3/4 654