Bryan Boilers & 300 ユーザーズマニュアル

ページ / 81
 
Date:  
8-4-2010 
 
Revision: 0 
 
Form:  
2396
 
interlocked with the boiler to prevent boiler 
operation if the dampers are closed. 
 
Combustion air openings must never be blocked 
or obstructed in any manner. 
 
The boiler room must be at a positive or neutral 
pressure relative to the outdoors.  A negative in 
the boiler room will result in downdraft problems 
and incomplete combustion due to the lack of 
air. 
 
WARNING! 
Failure to provide an adequate air 
supply will result in boiler damage and 
hazardous conditions in the building 
(fire and asphyxiation hazard as well 
as equipment damage). 
1.6.1 C
OMBUSTION 
A
IR 
O
PENINGS
The design of combustion air openings MUST 
comply with local and/or State codes or the 
authority having jurisdiction.  As a minimum, 
combustion air openings to the boiler room shall 
be provided as follows: 
Note: 
Combustion air provided solely from an indoor 
source is discouraged.  No dimension for a 
round or rectangular opening shall be less than 
3”. 
 
Two Permanent Opening Method 
 
One opening starting within 12” of the top of the 
boiler room and one starting within 12” of the 
bottom of the boiler room shall be provided.  The 
openings shall be open directly to the outside or 
ducted directly to the outside. 
 
When directly open to the outside or ducted to 
the outside by vertical ducts, each opening or 
duct shall have a minimum fee open area of 1 
in
2
 per 4000 BTU total input rating of the 
boiler(s) in the room. 
 
If ducted to the outside through horizontal 
ducts, each opening or duct shall have a 
minimum free area of 1 in
2
 per 2000 BTU total 
input rating of the boiler(s) in the room. 
 
One Permanent Opening Method 
 
One opening commencing within 12” of the top 
of the room shall be provided.  The opening 
shall be directly to the outside or shall be ducted 
to the outside with a horizontal or vertical duct.   
 
The opening or duct shall have a minimum free 
area of: 
 
1 in
2
 / 3000 BTU /hour of the total input ratting of 
all appliances (boilers) in the room. 
 
Not less than the sum of the areas of all vent 
connectors 
in the room.  A “vent connector” is 
defined as the pipe or duct that connects a fuel 
burning appliance to a vent or chimney. 
 
Additional area must be provided for other air 
consuming equipment in the room. 
 
Mechanical Air Supply Systems 
 
The combustion air supply may be provided by a 
mechanical air supply system.  If utilized, the 
combustion air must be provided from the 
outside at a minimum rate of 0.35 ft
3
/min. for 
every  1000 Btu/hr. input  for all appliances 
located in the space. 
 
If exhaust fans are utilized, additional air shall be 
provided to replace the exhausted air. 
 
Each boiler and other appliance must be 
interlocked to prevent operation when the 
mechanical air supply system is not in operation. 
 
If the combustion air is provided by a buildings 
mechanical ventilation system, the system shall 
be sized to provide the specified combustion air 
in addition to the ventilation air requirements. 
 
1.6.2 L
OUVERS
, G
RILLES
AND 
S
CREENS
 
 
Louvers and Grilles: 
 
The required size of openings for combustion, 
ventilation, and dilution air shall e based on the 
net free area of each opening.  Where the free 
area through a design of louver, grille, or screen 
is know, it shall be used in calculating the size 
opening required to provide the free area