York TL9E Series Скачать руководство пользователя страница 22

Страница: 22 / 34

5894307-UIM-B-0920

Johnson Controls Ducted Systems

Air Supply Openings and Ducts

• An opening can be used in lieu of a duct to provide the outside air

supply to an appliance unless otherwise permitted by the author-
ity having jurisdiction. The opening must be located within 12 in.
(30.5 cm) horizontally from the burner level of the appliance. See
the Combustion Air Source from Outdoors section and the COM-
BUSTION AIR AND VENT SAFETY section for additional infor-
mation, and see the venting safety check procedure on the
following page.

• The duct must be either metal or a material meeting the class 1

requirements of CAN4-S110 Standard for Air Ducts.

• The duct must be least the same cross-sectional area as the free

area of the air supply inlet opening to which it connects.

• The duct must terminate within 12 in. (30.5 cm) above and 24 in.

(61 cm) horizontally from the burner level of the appliance having
the largest input.

• A square or rectangular shaped duct must only be used when the

required free area of the supply opening is 9 in

(58.06 cm

) or

larger. When a square or rectangular duct is used, its small
dimension must not be less than 3 in. (7.6 cm).

• An air inlet supply from outdoors must be equipped with a means

to prevent the direct entry of rain and wind. Such means must not
reduce the required free area of the air supply opening.

• An air supply inlet opening from the outdoors must be located not

less than 12 in. (30.5 cm) above the outside grade level.

Combustion Air Source from Outdoors

• Two permanent openings, one within 12 in. (30.5 cm) of the top

and one within 12 in. (30.5 cm) of the bottom of the confined
space, must communicate directly or by means of ducts with the
outdoors, crawl spaces, or attic spaces.

• One permanent opening, commencing within 12 in. (30.5 cm) of

the top of the enclosure, is permitted where the equipment has
clearances of at least 1 in. (2.54 cm) from the sides and back and
6 in. (15.2 cm) from the front of the appliance. The opening must
communicate directly with the outdoors and have a minimum free
area of:

- 1 in.

/3,000 BTU/hr (700mm2/kW) of the total input rating

of all equipment located in the enclosure

- Not less than the sum of all vent connectors in the confined

space

• The duct must be least the same cross-sectional area as the free

area of the air supply inlet opening to which it connects.

• The blocking effects of louvers, grilles, and screens must be

given consideration in calculating free area. If the free area of a
specific louver or grille is not known, see Table 9.

Ventilated Combustion Air

The ventilated attic space or crawl space from which the combustion air
is taken must comply with the requirements specified in the Combustion
Air Source from Outdoors section in these instructions or in Section 5.3,
Air for Combustion and Ventilation of the National Fuel Gas Code, ANSI
Z223.1 (latest edition). This type of installation requires two correctly
sized pipes. One pipe brings combustion air from a correctly ventilated
attic space or crawl space and the second pipe extends from the fur-
nace vent connection (top right of unit) to the exterior of the building.
See Table 5 for intake pipe sizing, allowable length, and elbow usage.
Follow all notes, procedures, and required materials in the COMBUS-
TION AIR/VENT PIPE SIZING section when installing the combustion
air pipe from the unit and into a ventilated attic space or crawl space.

Note:

Do not terminate vent pipe in an attic or crawl space.

Ventilated Combustion Air Termination

See Figure 29 for required attic termination for the combustion air
intake pipe. For attic termination, use two 90° elbows with the open end
in a downward position. Make sure to maintain 12 in. (30.5 cm) clear-
ance above any insulation, flooring, or other material.
A crawl space combustion air installation consists of a straight pipe from
the PVC coupling on the burner box that extends into the crawl space
and terminates with a 1/4 in.(6.4 mm) mesh screen and no elbows.

Figure 28:

Ambient Combustion Air

Gable

Vent

Gas

Vent

Soffit

Vent

Ventilated

Attic

Top Above

Insulation