Figure 30: XAH horizontal right drain pan extension assembly
Installing the coil: XAU coils
About this task:
XAU coils are uncased upflow or downflow coils designed
for installation with a matching upflow or downflow
furnace.
These uncased coil installation instructions apply to
Johnson Controls Ducted Systems furnace models with a
supply air plenum of the size shown in Table 5 based on
the cabinet width of the furnace.
Table 5: Outer duct work dimensions
Coil size
Width (in.)
Depth (in.)
A
13 1/2
19 1/2
B
16 1/2
19 1/2
C
20
19 1/2
D
23 1/2
19 1/2
If the plenum is fabricated in two pieces, it is best
practice to use duct locks (for example, Pittsburgh lock
or snap lock) on the back side of the plenum. Three
standard S-Locks are fabricated and required for coil door
installation. Fabricate and install all duct work for housing
an uncased coil in accordance with local and/or national
codes.
The following installation steps are provided only for
reference for those who want to follow them. Experienced
sheet metal duct work technicians can choose to follow
their own practices, provided those practices comply with
local and/or national codes. This includes the standards of
the National Fire Protection Association for Installation of
Air-Conditioning and Ventilating Systems, NFPA No. 90B.
Note:
This procedure outlines how to install an XAU
coil and refers briefly to connecting the duct system,
installing a coil metering device, and connecting
,
more detailed instructions on these tasks.
1. Fold all four duct flanges on the furnace to the
upward position as shown in Figure 31.
Figure 31: Duct flanges
2. Fabricate the duct work to house the coil in
accordance with Figure 32 and Figure 33.
Installation Manual: XAF, XAH, and XAU Series - Full Cased and Uncased Coils for Cooling and Heat Pumps
22
Johnson Controls Ducted Systems
