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Bryant Induced-Combustion 4-Way Multipoise 310AAV User Manual

Page 10

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The Standard Method:

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).

The Known Air Infiltration Rate Method shall be used, 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 be determined per Table 3 or Equations 1 and 2.
Determine the minimum required volume for each appliance in the
space and add the volumes together to get the total minimum
required volume for the space.

Table 3-Minimum Space Volumes were determined by using the
following equations from the National Fuel Gas Code ANSI
Z223.1-2002/NFPA 54-2002,8.3.2.2
:

1. For other than fan-assisted appliances, such as a draft

hood-equipped water heater:

2. For fan-assisted appliances such as this furnace:

If:

I

other

= combined input of all other than fan-assisted appli-

ances in Btu/hr

I

fan

= combined input of all fan-assisted appliances in Btu/hr

ACH = air changes per hour (ACH shall not exceed 0.60.)

The following requirements apply to the Standard Method and to
the Known Air Infiltration Rate Method.

1. Adjoining rooms can be considered part of a space if:

a. There are no closable doors between rooms.

b. Combining spaces on same floor level. Each opening shall

have free area of at least 1 in.

2

/1,000 Btuh (2,000 mm

2

/kW)

of the total input rating of all gas appliances in the space,
but not less than 100 in.

2

(0.06 m

2

). One opening shall

commence within 12

″ (300 mm) of the ceiling and the

second opening shall commence within 12

″ (300 mm) of

the floor. The minimum dimension of air openings shall be
at least 3 in. (80 mm). (See Fig. 8.)

Fig. 7—Air for Combustion, Ventilation and

Dilution for Outdoors

A03174

1 SQ IN.

PER

4000

BTUH*

DUCTS

TO

OUTDOORS

1 SQ IN.
PER 4000
BTUH*

CIRCULA

TING

AIR DUCTS

VENT
THROUGH
ROOF

D

B

A

C

E

1 SQ IN.
PER 4000
BTUH*

DUCT

TO

OUTDOORS

CIRCULATING AIR DUCTS

1 SQ IN.
PER 2000
BTUH*

1 SQ IN.
PER 2000
BTUH*

DUCTS

TO

OUTDOORS

12

MAX

12

MAX

12

MAX

Use any of the following
combinations of openings:
A & B C & D D & E F & G

NOTE:

*Minimum dimensions of 3 in.

12

MAX

12

MAX

OUTDOORS

1 SQ IN.

PER

4000

BTUH*

F

G

CLEAR

ANCE IN FRONT

OF COMB

USTION AIR

OPENINGS SHALL BE

AT LEAST 3 IN.

A04002

Volume

Other

= 21ft

3

ACH

I

other

1000 Btu/hr

Fig. 8—Air for Combustion, Ventilation and

Dilution from Indoors

A03175

CIRCULATING AIR

DUCTS

6" MIN

(FRONT)

CIRCULATING AIR DUCTS

VENT THROUGH ROOF

1 SQ IN.
PER 1000
BTUH* IN DOOR
OR WALL

12" MAX

1 SQ IN.
PER 1000
BTUH* IN DOOR
OR WALL

12" MAX

* Minimum opening size is 100 sq in. with
minimum dimensions of 3 in.

Minimum of 3 in. . when type-B1 vent is used.

UNCONFINED
SPACE

INTERIOR

HEATED

SPACE

CLEARANCE IN FRONT OF COMBUSTION AIR

OPENINGS

SHALL

B

E

A

T

LEAST 3 IN.

A04003

Volume

Fan

= 15ft

3

ACH

I

fan

1000 Btu/hr

9