3
443 06 2403 01
Specifications subject to change without notice.
Figure 1
−
Upflow Ductwork Connections
B
B
A
A
A
A
Twinned Furnace
Common
Supply Air
Plenum
Common
Return
Air
Plenum
Example 1
Example 1 Notes:
Return duct cannot obstruct access to either furnace
Return Air can enter thru any combination of:
a. Left side only
b. Right side only
c. Bottom only
d. Back of platform when height of platform
equal Dimension A as shown
e. Any combination of a, b, c, d
Example 2 Notes:
When furnaces are installed Back-to-Back (not shown)
return duct MUST connect to the common return plenum
and side inlet of BOTH furnaces
Return duct cannot obstruct access to either furnace
Example 2
8 MIN
Common Return
Air Plenum
Return
Air
Plenum
Return
Air
Plenum
Twinned Furnace
Common
Supply Air
Plenum
A02223
Figure 2
−
Downflow/Horizontal Ductwork Connections
A
A
A
A
A
A
Common
Return
Air
Plenum
Common
Supply Air
Plenum
Twinned Furnaces
Common
Return
Air
Plenum
Common
Supply Air
Plenum
Twinned furnaces
Stacked* (80% ONLY)
Example 4 - Horizonal Applications
Example 4 Notes:
Do not connect return air to any side of furnace.
Do not stack condensing furnaces of top of each other
When furnaces are installed Side-by-Side (not shown),
return connection is similiar. Depth of plenum
Dimension A must equal to the front width of one furnace
Example 3 Notes:
Do not connect return air to any side of the
furnace
Connect return air plenum as shown
Example 3 - Downflow Applications
