II.
INSTALLATION IN UPFLOW AND DOWNFLOW
APPLICATIONS
NOTE:
For downflow applications, this furnace is approved for
use on combustible flooring when special base (available from
manufacturer) Part No. KGASB0201ALL is used. Special 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. 21.
3. Construct plenum to dimensions specified in Table 3 and
Fig. 21.
4. If downflow subbase (KGASB) is used, install as shown in
Fig. 22.
If Coil Assembly Part No. CD5 or CK5 or Coil Box Part
No. KCAKC is used, install as shown in Fig. 20.
NOTE:
Remove furnace perforated, discharge duct flanges when
they interfere with mating flanges on coil on downflow subbase.
To remove furnace perforated, discharge duct flange, use wide
duct pliers or duct flange tool or hand seamers to bend flange back
and forth until it breaks off. Be careful of sharp edges. (See Fig.
24.)
CAUTION:
UNIT MAY NOT OPERATE
Failure to follow this caution may result in intermittent
unit operation.
Do not bend duct flanges inward as shown in Fig. 21.
This will affect airflow across heat exchangers and may
cause limit cycling or premature heat exchanger failure.
Remove duct flange completely or bend it inward a
minimum of 210° as shown in Fig. 24.
NOTE:
For 140 size unit when installed in downflow orientation,
cut the white jumper wire off between terminals PL1-7 and PL1-9.
→
Fig. 18—Air for Combustion, Ventilation, and
Dilution for Outdoors
A03174
1 SQ IN.
PER
4000
BTUH*
DUCTS
TO
OUTDOORS
1 SQ IN.
PER 4000
BTUH*
CIRCULA
TING
AIR DUCTS
VENT
THROUGH
ROOF
D
B
A
C
E
1 SQ IN.
PER 4000
BTUH*
DUCT
TO
OUTDOORS
CIRCULATING AIR DUCTS
1 SQ IN.
PER 2000
BTUH*
1 SQ IN.
PER 2000
BTUH*
DUCTS
TO
OUTDOORS
12
″
MAX
12
″
MAX
12
″
MAX
Use any of the following
combinations of openings:
A & B C & D D & E F & G
NOTE:
*Minimum dimensions of 3 in.
12
″
MAX
12
″
MAX
OUTDOORS
1 SQ IN.
PER
4000
BTUH*
F
G
CLEAR
ANCE IN FRONT
OF COMB
USTION AIR
OPENINGS SHALL BE
AT LEAST 3 IN.
→
Fig. 19—Air for Combustion, Ventilation, and
Dilution from Indoors
A03175
CIRCULATING AIR
DUCTS
6" MIN
(FRONT)
†
CIRCULATING AIR DUCTS
VENT THROUGH ROOF
1 SQ IN.
PER 1000
BTUH* IN DOOR
OR WALL
12" MAX
1 SQ IN.
PER 1000
BTUH* IN DOOR
OR WALL
12" MAX
* Minimum opening size is 100 sq in. with
minimum dimensions of 3 in.
†
Minimum of 3 in. . when type-B1 vent is used.
UNCONFINED
SPACE
INTERIOR
HEATED
SPACE
CLEARANCE IN FRONT OF COMBUSTION AIR
OPENINGS
SHALL
B
E
A
T
LEAST 3 IN.
Fig. 20—Leveling Legs
A89014
1
3
⁄
4
″
1
3
⁄
4
″
1
3
⁄
4
″
1
3
⁄
4
″
5
⁄
16
″
5
⁄
16
″
5
⁄
16
″
5
⁄
16
″
—19—