Carrier 140/E Series Installation, Start--Up, Operating, And Service And Maintenance page 10

Indoor air is pernfitted 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.
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 deternfined per Table 3 or Equations 1 and 2.
Deternfine the minimum required volume for each appliance in
the space and add the volumes together to get the total nfininmm
required volume for the space.
Table 3-Minimum Space Volumes were deternfined by using
the following equations from the National Fuel Gas Code ANSI
Z223.1-2009/NFPA 54-2009, 9.3.2.2:
1. For other than fan-assisted appliances, such as a draft
hood-equipped water heater:
Volume - 21ft3 _
[ °ther
Other ACH 000 Btu/hr
2. For fan-assisted appliances such as this furnace:
Volume _ 15ft 3 _ I fan
Fan ACH 000 Btu/hr
A04002
A04003
If:
Iother = combined input of all other than fan-assisted appliances
in Btuh/hr
Ifan = combined input of all fan-assisted appliances in Btuh/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 closeable doors between rooms.
b. Combining spaces on same floor level. Each opening
shall have free area of at least 1 in.2/l,000 Btuh (2,000
mm2/kW) of the total input rating of all gas appliances
in the space, but not less than 100 in. 2 (0.06 m2). One
opening shall commence within 12-in. (300 ram) of the
ceiling and the second opening shall commence within
12-in. (300 ram) of the floor. The nfininmm dimension
of air openings shall be at least 3-in. (80 ram). (See Fig.
8.)
10
INTERIOR
HEATED
SPACE
1 1
I I
CIRCULATING AIR
DUCTS
I
I
II
I I
VENT THROUGH ROOF
:305mm)
1 SQ iN.
PER 1000
BTUH* IN DOOR
OR WALL
UNCONFINED
SPACE
6" MIN (152mm)
(FRONT)0
CIRCULATING AIR DUCTS
1 SQ IN.
PER 1000
BTUH* IN DOOR
OR WALL
L 12" MAX (3O5mm)
* Minimum opening size is 100 sq in. (64516 sq, mm)with minimum dimensions
of 3 in. (76 mm)
1- Minimum of 3 in. (76 mm) when type-B1 vent is used.
A03175
Fig. 8 - Air for Combustion, Ventilation, and Dilution from
Indoors
c. Combining space on different floor levels. The volumes
of spaces on different floor levels shall be considered as
communicating spaces if connected by one or more per-
manent openings in doors or floors having free area of
at least 2 in.2/l,000 Btuh (4,400 mm2/kW) of total input
rating of all gas appliances.
2. An attic or crawlspace may be considered a space that
freely conmmnicates with the outdoors provided there are
adequate permanent ventilation openings directly to out-
doors having free area of at least 1 -in.2/4,000 Btuh of total
input rating for all gas appliances in the space.
3. In spaces that use the Indoor Combustion Air Method,in-
filtration should be adequate to provide air for combus-
tion, permanent ventilation and dilution of flue gases.
However, in buildings with unusually tight construction,
additional air MUST be provided using the methods de-
scribed in the Outdoor Combustion Air Method section.
Unusually tight construction is defined as construction with:
a. Walls and ceilings exposed to the outdoors have a con-
tinuous, sealed vapor barrier. Openings are gasketed or
sealed and
b. Doors and openable windows are weatherstripped and
c. Other openings are caulked or sealed. These include
joints around window and door frames, between sole
plates and floors, between wall-ceiling joints, between
wall panels, at penetrations for plumbing, electrical and
gas lines, etc.
Combination of Indoor and Outdoor Air
1. Indoor openings shall comply with the Indoor Combus-
tion Air Method below and,