Air For Combustion And Ventilation; Supply-Air Plenum Installation (Downflow); Downflow Installation; Installation On A Combustible Floor - Carrier WeatherMaker 8000 Installation, Start-Up, And Operating Instructions Manual

c. If the furnace is installed on a raised platform to provide a
return-air plenum, and return air is taken directly from the
hallway or space adjacent to the furnace, all air for
combustion must come from outdoors. (See Fig. 3.)
DUCTS TO
OUTDOORS
12" MAX
1 SQ IN.
RETURN
A
VENT
PER 2000
AIR
THROUGH
BTUH *
ROOF
(CATEGORY I)
DUCTS
TO
OUTSIDE
1 SQ IN.
B
PER 2000
BTUH *
12" MAX
SUPPLY AIR
* Minimum dimensions of 3-In.
NOTE: Use any of the following
combinations of openings:
A & B C & D D & E
Fig. 3—Air for Combustion and Ventilation
(Outside Air)
2. All air from outside the structure:
a. If combustion air is taken from outdoors through vertical
ducts, the openings and ducts MUST have at least 1 sq in.
of free area per 4000 Btuh of the total input for all
equipment within the confined space.
For Example:
58ZAV FURNACE FREE AREA PER
INPUT BTUH OPENING (SQ IN.)
46,000
69,000
92,000
115,000
135,000
b. If combustion air is taken from the outdoors through
horizontal ducts, the openings and ducts MUST have at
least 1 sq in. of free area per 2000 Btuh of the total input
for all equipment within the confined space.
1 SQ IN.
PER 4000
BTUH
*
D
12"
MAX
F
1 SQ IN.
PER 4000
BTUH
*
OUTDOORS
1 SQ IN.
PER 4000
BTUH
*
G
E
12"
MAX
C
12" MAX
DUCT
1 SQ IN.
TO
PER 4000
OUTDOORS
BTUH
F & G
A93388
ROUND PIPE
(IN. DIA)
11.5 4
17.3 5
23.0 6
28.8 7
34.5 7
For Example:
58ZAV FURNACE IN-
PUT BTUH
46,000
69,000
92,000
115,000
135,000
c. When ducts are used, they must be of the same cross-
sectional area as the free area of the openings to which they
connect. The minimum dimension of rectangular ducts
must not be less than 3 in. (See Fig. 3.)
Step 3—Supply-Air Plenum Installation
(Downflow)
→

DOWNFLOW INSTALLATION

NOTE: This furnace is approved for use on combustible flooring
when manufacturer's
KGASB0201ALL is used. Manufacturer's accessory floor base is
not required when this furnace is installed on manufacturer's Coil
Assembly Part No. CD5 or CK5, or Coil Box Part No. KCAKC is
used.
1. Determine application being installed from Table 3.
2. Construct hole in floor per dimensions specified in Table 3
and Fig. 4.
3. Construct plenum to dimensions specified in Table 3.
4. If downflow subbase (KGASB) is used, install as shown in
Fig. 5.
If coil assembly CD5, CK5, or Coil Box KCAKC is used,
install as shown in Fig. 6.

INSTALLATION ON A COMBUSTIBLE FLOOR

1. Cut and frame hole in floor per dimensions in Installation
Instructions packaged with downflow subbase.
2. When completed, downflow subbase, plenum, and furnace (or
coil casing when used) should be installed as shown in Fig. 6.
5
FREE AREA PER ROUND PIPE
OPENING (SQ IN.) (IN. DIA)
23.0 6
34.3 7
46.0 8
57.6 9
69.0 10
accessory floor base Part No.