Bryant 912S, Installation, Operating And Service Instructions

Page: 22 / 85

22
Return Air Connections
FIRE HAZARD
A failure to follow this warning could cause personal injury,
death and/or property damage.
Never connect return
− air ducts to the back of the furnace.
Follow instructions below.
!
WARNING
The return − air duct must be connected to bottom, sides (left or
right), or a combination of bottom and side(s) of main furnace
casing. Bypass humidifier may be attached into unused return air
side of the furnace casing. See Fig. 27, 30, and 29.
Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return − air opening. Remove and discard this panel when
bottom return air is used. To remove bottom closure panel, see Fig.
23 and 24.
Side Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return − air opening. This panel MUST be in place when
only side return air is used. Where required by code, seal bottom
closure to furnace with tape, mastic or other durable sealing
method.
NOTE : Side return − air openings can be used in UPFLOW and
some HORIZONTAL configurations. Do not use side return − air
openings in DOWNFLOW configuration. See Fig. 27, 30, and 29.
Leveling Legs (If Desired)
In upflow position with side return inlet(s), leveling legs may be
used. See Fig. 25. Install field − supplied, 5/16 x 1 − 1/2 in. (8 x 38
mm) (max) corrosion − resistant machine bolts, washers and nuts.
NOTE : Bottom closure must be used when leveling legs are used.
It may be necessary to remove and reinstall bottom closure panel to
install leveling legs. To remove bottom closure panel, see Fig. 23
and 24.
To install leveling legs:
1. Position furnace on its back. Locate and drill a hole in each
bottom corner of furnace.
2. For each leg, install nut on bolt and then install bolt with
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 in-
side nut to secure arrangement.
5. Reinstall bottom closure panel if removed.
Downflow Installation
NOTE:
The furnace must be pitched as shown in Fig. 26 for
proper condensate drainage.
Supply Air Connections
NOTE : For downflow applications, this furnace is approved for
use on combustible flooring when any one of the following 3
accessories are used:
Special Base, KGASB
Cased Coil Assembly Part No. CNPV, CNRV, CAP, or CAR
Coil Box Part No. KCAKC
1. Determine application being installed from Table 8.
2. Construct hole in floor per Table 8 and Fig. 21.
3. Construct plenum to dimensions specified in Table 8 and
Fig. 21.
4. Install special base coil assembly or coil box as shown in
Fig. 21.
NOTE : It is recommended that the perforated supply − air duct
flanges be completely removed from furnace when installing the
furnace on a factory
− supplied cased coil or coil box. To remove the
supply − air duct flange, use wide duct pliers or hand seamers to
bend flange back and forth until it breaks off. Be careful of sharp
edges. See Fig.
22.
CUT HAZARD
Failure to follow this caution may result in personal injury.
Sheet metal parts may have sharp edges or burrs. Use care
and wear appropriate protective clothing, safety glasses and
gloves when handling parts, and servicing furnaces.
CAUTION
!
Connect supply − air duct to supply − air outlet on furnace. Bend
flange inward past 90 with wide duct pliers See Fig. 22. The
supply − air duct must be connected to ONLY the furnace supply
outlet or air conditioning coil casing (when used). When installed
on combustible material, supply − air duct must be connected to
ONLY
the factory − approved accessory subbase, or a
factory − approved air conditioning coil casing. DO NOT cut main
furnace casing to attach supply side air duct, humidifier, or other
accessories. All supply side accessories MUST be connected to
duct external to furnace casing.
Return Air Connections
FIRE HAZARD
A failure to follow this warning could cause personal injury,
death and/or property damage.
Never connect return
− air ducts to the back of the furnace.
Follow instructions below.
!
WARNING
The return − air duct must be connected to return − air opening
(bottom inlet). DO NOT cut into casing sides (left or right).
Bypass humidifier connections should be made at ductwork or coil
casing sides exterior to furnace. See Fig. 30.
Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return − air opening. Remove and discard this panel when
bottom return air is used. To remove bottom closure panel, see Fig.
23 and 24.
Horizontal Installation
NOTE:
The furnace must be pitched forward as shown in Fig. 26
for proper condensate drainage.
FIRE, EXPLOSION, AND CARBON MONOXIDE
POISONING HAZARD
Failure to follow this warning could result in personal
injury, death, or property damage.
Do not install the furnace on its back or hang furnace with
control compartment facing downward. Safety control
operation will be adversely affected. Never connect
return − air ducts to the back of the furnace.
!
WARNING
912S