Carrier 58PB - Step 2 - Provide Air for Combustion and; Step 3 - Assemble Furnace; Draft Hood

HEATING & COOLING
58ED,PB
Horizontal Gas-Fired Furnaces
Table 3 — Alcove Clearances (in.)
TOP
SIDES
BACK
DRAFT
HOOD
SINGLE
WALL VENT
8
6
8*
18f
Line
Contact
6
•With draft hood in front of furnace
fWith draft hood on back of furnace
Step 2 — Provide Air For Combustion and
Ventilation — For an unconfined space (more than
50 cu ft of volume per 1,000 Btu of aggregate input rating
of all appliances installed in that space) such as a base¬
ment or attic, infiltration air is normally adequate to
provide air for combustion, ventilation and dilution of
flue gases. Adjoining rooms may be included if there are
no doors between the rooms
For a confined space, where air is taken from an
interior space, 2 permanent openings of equal area are
required. One opening must be within 12 in. of the ceiling
and the other must be within 12 in. of the floor. Each
opening must have a free area of at least 1 sq in. per
1000 Btu of total input rating but not less than 100 sq
inches.
If the outside air is supplied to a confined space, then
the 2 openings must be equal and located as above and
the free area of each must be:
A CAUTION
Whenever this furnace is installed in an area along
with one or more gas appliances, the total Btu input
of all appliances must be included when determining
the free area requirements for combustion and
ventilation air openings.
When ducts are used, they must be of the same cross-
sectional area as the free area of the openings to which
they connect. The minimum dimension of rectangular
air ducts must not be less than 3 inches.
The free area through a design of louver or grille
should be used in calculating the size opening required
to provide the free area specified. If the design and free
area is not known, it may be assumed that wood louvers
have 20-25% free area and metal louvers and grilles have
60-75% free area. Screens used must not be smaller than
1 /4 in. mesh and louvers shall be fixed in the open posi¬
tion or interlocked with the equipment so that they are
opened automatically during equipment operation.
A WARNING
Do not block the combustion air openings in the
furnace. Any blockage will result in improper com¬
bustion and may result in a fire hazard or unsafe
condition
1. Onesqin. per 4,000 Btu of total input rating when
the air is directly communicated from the outdoors.
2. One sq in. per 4,000 Btu of total input rating when
the air is brought in through vertical ducts.
3 One sq in. per 2,000 Btu of total input rating when the
air is transferred through horizontal ducts.
LINE CONTACT ONLY
PERMISSIBLE BETWEEN
TOP CORNERS OF FURNACE
AND BUILDING JOISTS,
STUDS OR FRAMING.
KEEP ALL INSULATING
MATERIAL CLEAR OF
FURNACE. INSULATING
MATERIALS MAY BE
COMBUSTIBLE.
METAL EXTENDING 12 IN. FROM
UNDER COMBUSTION CHAMBER
Fig. 2 — Attic Installation Showing Point Contact
A CAUTION
For an attic installation, keep insulation 12 in. or
more away from any furnace openings. Some types
of insulating materials may be combustible.
Step 3 — Assemble Furnace — The burner and
controls are shipped in place and the furnace high- and
low-voltage wiring is complete to facilitate the installa¬
tion. Low-voltage wiring to the field-supplied thermostat
is necessary to complete the unit wiring (see Step 7 —
Make Electrical Connections).
In order to accommodate all the possible field installa¬
tions that may exist, the unit is designed so that the gas
valve, controls and draft hood assembly may be
assembled on either side of the furnace. Refer to Com¬
ponent Reversal section for details. After reversal (if
required), return to this section.
A CAUTION
Remove cardboard shipping insert from eye of the
blower scroll before energizing blower.
DRAFT HOOD — In order to save shipping space the
draft hood is shipped disassembled (on models 125 and
140 the left panel is spotwelded in place). Remove the
draft hood components from the blower compartment
(on some models the panels might be packed outside the
furnace jacket). On the models 50, 75 and 100 there will
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book I I 1 4 PC101 Catalog No 535-834 Printed in U S A Form 58ED.PB-1 SI Pg 3 6-85 Replaces: 58PB-1SI
Tab l6a 18a For replacement items use Carrier Specified Parts