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-- 21 --
Combination of Indoor and Outdoor Air
1. Indoor openings shall comply with the
Indoor
Combustion Air
Method below and,
2. Outdoor openings shall be located as required in the
Outdoor Combustion Air
Method mentioned previously
and,
3. Outdoor openings shall be sized as follows:
a. Calculate the Ratio of all Indoor Space volume divided
by required volume for
Indoor Combustion Air
Method below.
b. Outdoor opening size reduction
Factor
is 1 minus the
Ratio
in a. above.
c. Minimum size of Outdoor openings shall be the size
required in
Outdoor Combustion Air
Method above
multiplied by reduction
Factor
in b. above. The
minimum dimension of air openings shall be not less
than 3-in. (76 mm).
INSTALLATION
NOTE
: The 140 size unit may not be installed in non-direct vent
(1-pipe) applications.
Step 1 -- Leveling Legs (If Desired)
When furnace is used in upflow position with side inlet(s),
leveling legs may be desired. (See Fig. 20.) Install field-supplied,
corrosion-resistant 5/16-in. (8 mm) machine bolts and nuts.
NOTE
: The maximum length of bolt should not exceed 1-1/2 in.
(38 mm).
1. Position furnace on its back. Locate and drill a 5/16-in. (8
mm) diameter hole in each bottom corner of furnace. (See
Fig. 20.) Holes in bottom closure panel may be used as
guide locations.
2. For each hole, install nut on bolt and then install bolt and
nut in hole. (Install flat washer if desired.)
3. Install another nut on other side of furnace base. (Install
flat washer if desired.)
4. Adjust outside nut to provide desired height, and tighten
inside nut to secure arrangement.
NOTE
: Bottom closure must be used when leveling legs are
used. See Bottom Closure Panel section.
1
3
/
4
″
1
3
/
4
″
1
3/
4
″
1
3/
4
″
5/
16
″
5
/
16
″
5/
16
″
5/
16
″
(44mm)
(8mm)
(44mm)
(8mm)
(8mm)
(8mm)
(44mm)
(44mm)
A89014
Fig. 20 -- Leveling Legs
Step 2 -- Installation in Upflow or 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. CNPV, CAPV, CAP or CAR, 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. CNPV, CAPV, CAP or CAR or
Coil Box Part No. KCAKC is used, install as shown in
Fig. 23.
NOTE
: Remove furnace perforated, discharge duct flanges when
they interfere with mating flanges on coil on downflow sub base.
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.)
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. 24. 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.
CAUTION
!
NOTE
: For 140 size unit when installed in downflow orientation,
cut the white jumper wire off between terminals PL1--7 and PL1--9.
Do not cut white jumper between terminals PL1--7 and PL1--11.
Refer to Fig. 31 for location of jumper. Cut jumper close to
connector and remove wire to avoid a short circuit.
Step 3 -- Installation in Horizontal Applications
UNIT MAY NOT OPERATE
Failure to follow this caution may result in intermittent
unit operation.
The entire length of furnace MUST be supported when
furnace is used in a horizontal position to ensure proper
draining. When suspended, bottom brace supports sides and
center blower shelf. When unit is supported from the ground,
blocks or pad should support sides and center blower
shelf area.
CAUTION
!
These furnaces can be installed horizontally in either horizontal
left or right discharge position. In a crawlspace, furnace can
either be hung from floor joist or installed on suitable blocks or
pad. Furnace can be suspended from each corner by hanger bolts
and angle iron supports. (See Fig. 25.) Cut hanger bolts (4 each
3/8-in. (10 mm) all-thread rod) to desired length. Use 1 X 3/8-in.
flat washers, 3/8-in. lock washers, and 3/8-in. nuts on hanger rods
as shown in Fig. 25. Dimples are provided for hole locations.
(See Fig. 2.)
58MCB