Air For Combustion And Ventilation - Bryant 987MB Installation, Start-Up, Operating And Service And Maintenance Instructions

987MB: Installation, Start-up, Operating and Service and Maintenance Instructions
The following types of furnace installations may require OUTDOOR
AIR for combustion due to chemical exposures:
• Commercial buildings
• Buildings with indoor pools
• Laundry rooms
• Hobby or craft rooms
• Chemical storage areas
If air is exposed to the following substances, it should not be used for
combustion air, and outdoor air may be required for combustion:
• Permanent wave solutions
• Chlorinated waxes and cleaners
• Chlorine based swimming pool chemicals
• Water softening chemicals
• De-icing salts or chemicals
• Carbon tetrachloride
• Halogen type refrigerants
• Cleaning solvents (such as perchloroethylene)
• Printing inks, paint removers, varnishes, etc.
• Hydrochloric acid
• Cements and glues
• Antistatic fabric softeners for clothes dryers
• Masonry acid washing materials
All fuel-burning equipment must be supplied with air for fuel
combustion. Sufficient air must be provided to avoid negative pressure
in the equipment room or space. A positive seal must be made between
the furnace cabinet and the return-air duct to prevent pulling air from the
burner area.

AIR FOR COMBUSTION AND VENTILATION

Introduction
Direct Vent (2-pipe) Applications
When the furnace is installed as a direct vent (2-pipe) furnace, no special
provisions for air for combustion are required. However, other gas
appliances installed in the space with the furnace may require outside air
for combustion. Follow the guidelines below to ensure that other gas
appliances have sufficient air for combustion.
Ventilated Combustion Air Applications (for U.S. Only)
When the furnace is installed using the ventilated combustion air option,
the attic or crawlspace must freely communicate with the outdoor to
provide sufficient air for combustion. The combustion air pipe cannot be
terminated in attics or crawlspaces that use ventilation fans designed to
operate during the heating season. If ventilation fans are present in these
areas, the combustion air pipe must terminate outdoors as a Direct Vent/
2-Pipe system.
All air for combustion is piped directly to the furnace from a space that is
well ventilated with outdoor air (such as an attic, crawl space, or
equipment closet) and the space is well isolated from the living space or
garage. In addition, other gas appliances installed in the space with the
furnace may require outside air for combustion. Follow the guidelines
below to ensure that the roof or crawlspace walls have sufficient free
area to provide sufficient air for combustion and ventilation for the
furnaces. The guidelines below can be used to ensure that other gas
appliances have sufficient air for combustion.
Provisions for adequate combustion, ventilation, and dilution air must be
provided in accordance with:
• U.S.A. Installations: Section 9.3 of the current edition of NFPA
54/ANSI Z223.1, Air for Combustion and Ventilation and applicable
provisions of the local building codes.
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
!
FURNACE CORROSION HAZARD
Failure to follow this caution may result in furnace damage.
Air for combustion must not be contaminated by halogen compounds,
which include fluoride, chloride, bromide, and iodide. These elements
can corrode heat exchangers and shorten furnace life. Air contaminants
are found in aerosol sprays, detergents, bleaches, cleaning solvents,
salts, air fresheners, and other household products.
!
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal injury or death.
The operation of exhaust fans, kitchen ventilation fans, clothes dryers,
attic exhaust fans or fireplaces could create a NEGATIVE PRESSURE
CONDITION at the furnace. Make-up air MUST be provided for the
ventilation devices, in addition to that required by the furnace. Refer to
the Carbon Monoxide Poisoning Hazard warning in the venting section
of these instructions to determine if an adequate amount of make-up air
is available.
Outdoor Combustion Air Method
1. Provide the space with sufficient air for proper combustion,
ventilation, and dilution of flue gases using permanent horizontal or
vertical duct(s) or opening(s) directly communicating with the
outdoors or spaces that freely communicate with the outdoors.
2. Fig. 6 illustrates how to provide TWO OUTDOOR OPENINGS,
one inlet and one outlet combustion and ventilation air opening, to
the outdoors.
a. One opening MUST commence within 12 in. (300 mm) of the
ceiling and the second opening MUST commence within 12 in.
(300 mm) of the floor.
b. Size openings and ducts per
c. TWO HORIZONTAL DUCTS require 1 sq. in. (645 sq. mm) of
free area per 2,000 BTUh (1,100 mm2/kW) of combined input
for all gas appliances in the space per
d. TWO OPENINGS OR VERTICAL DUCTS require 1 sq. in.
(645 sq. mm) of free area per 4,000 BTUh (550 mm2/kW) for
combined input of all gas appliances in the space per
Table 3.
3. ONE OUTDOOR OPENING requires:
a. 1 sq. in. (645 sq. mm) of free area per 3,000 BTUh (734
mm2/kW) for combined input of all gas appliances in the space
per Fig. 6 and Table
b. Not less than the sum of the areas of all vent connectors in the
space.
The opening shall commence within 12 in. (300 mm) of the ceiling.
Appliances in the space shall have clearances of at least 1 in. (25 mm)
from the sides and back and 6 in. (150 mm) from the front. The opening
shall directly communicate with the outdoors or shall communicate
through a vertical or horizontal duct to the outdoors or spaces (crawl or
attic) that freely communicate with the outdoors.
8
CAUTION
WARNING
Fig. 6 and Table 3.
Fig. 6 and Table
3.
3.
Fig. 6 and