![background image](http://html.mh-extra.com/html/carrier/bryant-915sb/bryant-915sb_installation-start-up-operating-and-service-and-maintenance-instructions_2562921005.webp)
915SB: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
5
INTRODUCTION
A12181
Fig. 2 – Multipoise Orientations
This 4-way multipoise Category IV condensing furnace is CSA
design-certified as a direct-vent (2-pipe) furnace for 40,000 BTUh
through 140,000 BTUh models using outside air for combustion. The
26,000 BTUh model can use the same 2-pipe venting system using
outside air for combustion but is not considered direct vent.
A non-direct vent (1-pipe) furnace for all models using indoor air for
combustion or from a well-ventilated attic or crawl space, where
permitted by local code. See
. The furnace is factory-shipped for
use with natural gas. The furnace can be converted in the field for use
with propane gas when a factory-supplied conversion kit is used. Refer
to the furnace rating plate for conversion kit information.
These furnaces are not approved for installation in recreational vehicles
or outdoors. Single-stage furnaces (40,000 BTUh through 120,000
BTUh) are approved for installation in manufactured housing/mobile
homes with manufacturer-approved accessory. The accessory conversion
kit is required for use with both natural and propane gas. The furnace
must also be installed on a factory-supplied accessory combustible floor
base or evaporator coil casing.
This furnace is designed for minimum continuous return-air temperature
of 60°F (15°C) db or intermittent operation down to 55°F (13°C) db such
as when used with a night setback thermostat. Return-air temperature
must not exceed 80°F (27°C) db. Failure to follow these return-air
temperature limits may affect reliability of heat exchangers, motors, and
controls. See
.
A150573
Fig. 3 – Freeze Protection and Return Air Temperature
The furnace should be sized to provide 100 percent of the design heating
load requirement plus any margin that occurs because of furnace model
size capacity increments. None of the furnace model sizes can be used if
the heating load is 12,000 BTU or lower. Use Air Conditioning
Contractors of America (Manual J and S); American Society of Heating,
Refrigerating, and Air-Conditioning Engineers; or other approved
engineering method to calculate heating load estimates and select the
furnace. Excessive oversizing of the furnace may cause the furnace
and/or vent to fail prematurely, customer discomfort and/or vent
freezing.
Failure to follow these guidelines is considered faulty installation and/or
misapplication of the furnace; and resulting failure, damage, or repairs
may impact warranty coverage.
For accessory installation details, refer to the applicable instruction
literature.
NOTE:
Remove all shipping materials, loose parts bag, and literature
before operating the furnace. See
.
Table 2 – Loose Parts Bag
NOTE:
The 26K and 40K models are the only furnaces that receive the
outlet restrictor in loose parts bag. See Maximum Equivalent Vent
Length Table for usage.
A12182
Fig. 4 – Prohibited Installations
NOTICE
!
IMPORTANT INSTALLATION AND START-UP PROCEDURES
Failure to follow this procedure may result in a nuisance smoke or odor
complaint.
The manifold pressure, gas rate by meter clocking, temperature rise and
operation must be checked after installation. Minor smoke and odor
may be present temporarily after start-up from the manufacturing
process. Some occupants are more sensitive to this minor smoke and
odor. It is recommended that doors and windows be open during the
first heat cycle.
THE BLOWER IS LOCATED
TO THE RIGHT OF THE
BURNER SECTION, AND
CONDITIONED AIR IS
DISCHARGED TO THE LEFT.
THE BLOWER IS
LOCATED BELOW THE
BURNER SECTION, AND
CONDITIONED AIR IS
DISCHARGED UPWARD.
THE BLOWER IS
LOCATED ABOVE THE
BURNER SECTION, AND
CONDITIONED AIR IS
DISCHARGED DOWNWARD
THE BLOWER IS
LOCATED TO THE LEFT
OF THE BURNER SECTION,
AND CONDITIONED AIR IS
DISCHARGED TO THE RIGHT.
60
80
/ 27˚C
/ 16˚C
SUPPLY AIR
SEE PRODUCT DATA FOR
ACCESSORY CONDENSATE
TRAP HEATER AND CONDENSATE
DRAIN LINE PROTECTION.
DESCRIPTION
QUANTITY
Outlet Restrictor Plate (provided with 26K and 40K
BTUH furnaces only; see Note)
1
Air Intake Pipe Flange
1
Vent Pipe Flange
1
Pipe Flange Gaskets
2
Sharp Tip Screws (Vent and Inlet Flanges)
10
Vent Pipe Coupling
1
Vent Pipe Coupling Clamps
2
Pressure Switch Tube
1
Rubber Drain Elbow
1
Drain Tube Clamps
4
1/2-in. CPVC to 3/4-in. PVC Pipe Adapter
1
Gas Line Grommet
1
Junction Box Cover
1
Junction Box Base
1
Green Ground Screw
1
Blunt Tip Screws (Junction Box)
3
Thermostat Wire Grommet
1
Drain Extension Tube (Z-pipe) (Provided separately in
furnace)
1
WARNING
!
FIRE HAZARD
Failure to follow this warning could result in personal injury, death
and/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
BACK POSITIONED
DOWNWARD
AIR RETURN
CUT IN BACK
BACK POSITIONED
UPWARD