Ach | Carrier 58PHA/PHX guide

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 Fig. 7 and Table 2.

c.TWO HORIZONTAL DUCTS require 1 square inch of free area per 2,000 Btuh (1,100 mm2/kW) of combined input for all gas appliances in the space per Fig. 7 and Table 2.

d.TWO OPENINGS OR VERTICAL DUCTS require 1 square inch of free area per 4,000 Btuh (550 mm2/kW) for combined input of all gas appliances in the space per Fig. 7 and Table 2.

3.ONE OUTDOOR OPENING requires:

a.1 square inch of free area per 3,000 Btuh (734 mm2/kW) for combined input of all gas appliances in the space per Table 2 and

b.Not less than the sum of the areas of all vent connectors in the space.

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.

						1 SQ IN.
	DUCTS					PER 4000
	DUCTS					BTUH*
	TO					BTUH*
	TO
	OUTDOORS
(305mm) 12″ MAX					D	12″	(305mm)
1 SQ IN.					VENT	MAX	(305mm)
PER 2000	B				THROUGH	F
BTUH*	CIRULATINGC	AIR DUCTS			ROOF	1 SQ IN.
						1 SQ IN.
						PER
						4000
						BTUH*
						BTUH*
DUCTS		OF COMBUSTION AIR	OPENINGS SHALL BE			OUTDOORS
TO
OUTDOORS				AT LEAST 3 IN.

						1 SQ IN.
						PER
						4000
1 SQ IN.						BTUH*
1 SQ IN.					E	G
PER 2000	A				E	G
BTUH*	RONTLEARANCINCEF				mm)(76	12″	(305mm)
(305mm) 12″ MAX					C	MAX	(305mm)
					12″ MAX
					(305mm)
CIRCULATING AIR DUCTS					DUCT	1 SQ IN.
					DUCT	1 SQ IN.
					TO	PER 4000
					OUTDOORS	BTUH*

*Minimum dimensions of 3 in. (76 mm).

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

A03174

Fig. 7 - Air for Combustion, Ventilation, and Dilution from

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-InfiltrationMethod is used.

!WARNING

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 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

Z223.1-2006/NFPA 54-2006, 9.3.2.2:

1.For other than fan-assisted appliances, such as a draft hood-equipped water heater:

Volume	=	21ft3	I other
		ACH	1000 Btu/hr
Other

A04002

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

Volume	=	15ft3	I fan
		ACH	1000 Btu/hr
Fan

A004003

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 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 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” (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.)

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 permanent openings in doors or floors having free area