Bryant 810SA Installation, Start-Up, Operating And Service And Maintenance Instructions page 6

810SA/811SA: Installation, Start–Up, Operating and Service and Maintenance Instructions
b. Not less than the sum of the areas of all vent connectors in the
space.
DUCTS
TO
OUTDOORS
(305mm) 12" MAX
1 SQ IN.
PER 2000 B
BTUH*
DUCTS
TO
OUTDOORS
1 SQ IN.
PER 2000
A
BTUH*
(305mm)
12" MAX
CIRCULATING AIR DUCTS
*Minimum dimensions of 3 in. (76 mm).
NOTE: Use any of the following combinations of openings:
A&B, C&D, D&E, F&G
Fig. 6 – Air for Combustion, Ventilation,
and Dilution for Outdoors
Table 1 – Minimum Free Area Required for Each Combustion Air Opening or Duct to Outdoors
TWO HORIZONTAL DUCTS
(1 SQ. IN./2,000 BTUH)
FURNACE
INPUT (BTUH)
Free Area of Opening
and Duct
(sq. in. / sq. mm)
44,000 22 (14193)
66,000 33 (21290)
88,000 44 (28387)
110,000 55 (35484)
132,000 66 (42581)
154,000 77 (49677)
FURNACE WATER HEATER
110,000 +
66,000 +
88,000 +
The Standard Method
Use the Standard Method if:
1. The space has no less volume than 50 cubic feet per 1,000 Btuh of
the maximum input ratings for all gas appliances installed in the
space and
2. The air infiltration rate is not known to be less than 0.40 air changes
per hour (ACH).
Use the Known Air Infiltration Rate Method if the infiltration rate is
known to be:
1. Less than 0.40 ACH and
2. Equal to or greater than 0.10 ACH
Infiltration rates greater than 0.60 ACH shall not be used. The minimum
required volume of the space varies with the number of ACH and shall
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
1 SQ IN.
PER 4000
BTUH*
D 12"
(305mm)
MAX
VENT
THROUGH
F
ROOF
1 SQ IN.
PER
4000
BTUH*
1 SQ IN.
PER
4000
BTUH*
E
G
12"
(305mm)
MAX
C
12" MAX
(305mm)
DUCT
1 SQ IN.
TO
PER 4000
OUTDOORS
BTUH*
(1,100 SQ. MM/KW)
Round Duct Diameter
(in./mm)
6 (152)
7 (178)
8 (203)
9 (229)
10 (254)
10 (254)
EXAMPLES: Determining Free Area
30,000 = (140,000 divided by 4,000)
40,000 = (106,000 divided by 3,000)
30,000 = (118,000 divided by 2,000)
The opening shall commence within 12" (300 mm) of the ceiling.
Appliances in the space shall have clearances of at least 1" (25 mm)
from the sides and back and 6" (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.
– Indoor Combustion Air NFPA & AGA
– Standard and Known-Air-Infiltration Rate Methods
– Indoor air is permitted for combustion, ventilation, and dilution, if
the Standard or Known-Air-Infiltration Method is used.
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in death and/or personal
injury.
Many homes require air to be supplied from outdoors for furnace
combustion, ventilation, and dilution of flue gases. The furnace
combustion air supply must be provided in accordance with this
instruction manual.
A03174
SINGLE DUCT OR OPENING
(1 SQ. IN./3,000 BTUH)
(734 SQ. MM/KW)
Free Area of Opening
Round Duct Diameter
and Duct
(in. / mm)
(sq. In. / sq. mm)
14.7 (9484) 5 (127)
22 (14193) 6 (152)
29.3 (18903) 7 (178)
36.7 (23677) 7 (178)
44 (28387) 8 (203)
51.3 (33096) 9 (229)
TOTAL INPUT
=
=
=
be determined per
required volume for each appliance in the space and add the volumes
together to get the total minimum required volume for the space.
Table 2 - Minimum Space Volumes were determined by using the
following equations from the current edition of National Fuel Gas Code
ANSI Z223.1/NFPA 54:
1. For other than fan-assisted appliances, such as a draft
hood-equipped water heater:
Volume
6
WARNING
!
TWO OPENINGS OR VERTICAL DUCTS
(1 SQ. IN./4,000 BTUH)
(550 SQ. MM/KW)
Free Area of
Opening and Duct
(sq. In. / sq. mm)
11 (7097)
16.5 (10645)
22 (14193)
27.5 (17742)
33 (21290)
38.5 (24839)
35.0 Sq. In. for each two Vertical Ducts or Openings
35.3 Sq. In. for a Single Duct or Opening
59.0 Sq. In. for each of two Horizontal Ducts
Table 2 or Equations 1 and 2. Determine the minimum
I
= 21ft 3
other
ACH 1000 Btu/hr
Other
Round Duct Diameter
(In./mm)
4 (102)
5 (127)
6 (152)
6 (152)
7 (178)
8 (203)
A04002