Page 11
Installer’s Guide
Figure 7. Typical Ground Level Applications
Note:
Use the extreme mount-
ing kit, BAYEXMK003A, to
secure the unit to the slab.
Step 4—Unit Installation
NOTE:
The factory ships this unit for horizontal installation.
Install Flue Hood
1. Locate the Flue Hood in the literature package.
2. Remove the two Flue Hood mounting screws from the unit.
They
are located to the right of the Power Entry connection panel.
3. Attach the Flue Hood to the unit with the two screws removed
in
step 2. See Figure 2 on page 5 or Figure 5 on page 8 for cor-
rect orientation of the Flue Hood.
Ground Level Installation
To install the unit at ground level:
1. Place the unit on a pad the size of the unit or larger. The unit must
be mounted level for proper drainage of water through the holes
in the base pan. To securely attach the unit to the slab, use
extreme mounting kit, BAYEXMK003A.
The pad must not come in contact with the structure (see Figure
7.) Be sure the outdoor portion of the supply and return air
ducts are as short as possible.
Unit requires vibration support as indicated in Figure 7 below
and in Figure 9 on page 13.
2. The louvers above and below the Flue Hood in the side
panel must have adequate clearance around the air
opening into the combustion area.
3. Location of the unit must allow service clearance around it.
Clearance of the unit must be given careful consideration. See
Figures 1 to 6, pages 4-9.
NOTE:
Any reduction of the unit clearances indicated in these
illustrations may result in condenser coil starvation or the
recirculation of warm condenser air. Actual clearances, which
appear to be inadequate should be reviewed with a local
engineer.
IMPORTANT:
A minimum 0” clearance to combustible mate-
rial shall be maintained on air outlet duct.
Rooftop Installation -- Curb Mounting
Convert Horizontal Airflow to Down Airflow
The factory ships the unit for horizontal airflow. Perform this
procedure to convert the unit to down airflow:
1. Remove the three (3) sheet metal screws securing the supply
aircover and the four (4) sheet metal screws securing the return
air cover from the base of the unit. Remove the covers from the
base. See Figure 8, page 12.
2. Place the covers over the horizontal supply and return open-
ings (painted side out). Align the screw holes, and secure using
the same screws removed in step 1.
4. Attach the supply and return air ducts to the unit as explained
in the following Ductwork Installation section on page 16.
5. Flexible duct connectors must be of a flame retardant material.
Insulate any ductwork outside of the structure with at least two
(2) inches of insulation and weatherproof. There must be a
weather proof seal where the duct enters the structure.
6. Do not expose the unit to direct roof water runoff.
7. Seal all holes through exterior walls in accordance with local
codes.
8. Continue with the following installation sections to complete
the installation: Ductwork on page 16, Gas Piping on page 16,
Filter on page 19, and Electrical Wiring on page 19.
Install Full Perimeter Roof Mounting Curb
1. Verify that the roof mounting curb is correct for the unit. There
are two curbs depending on the unit cabinet sizes:
•
4YCZ6024-036 uses model BAYCURB050A.
•
4YCZ6048 through 4YCZ6060 use model BAYCURB051A.
2. Assemble and install the curb following the instructions in the
Installer's Guide included with the curb.
SIDING
RETURN
AIR
DUCT
SUP-
PLY AIR
DUCT
EXTERIOR
WALL
INSULATE WEATH-
ERPROOF OR RAIN
SHIELD
FLEXIBLE DUCT
CONNECTORS
3/4" VIBRATION ISOLATORS, USE 7 ISOLATORS
AS SHOWN IN FIGURE 9, PAGE 13.
SUPPORT PAD FOUNDA-
TION
OUTDOOR AIR DIS-
CHARGE
