Carrier 58CTA Installation And Service Instructions Manual Download

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Not all horizontal furnaces are approved for side return air
connections. (See Fig. 20.)

FILTER ARRANGEMENT

FIRE, CARBON MONOXIDE AND POISONING
HAZARD
Failure to follow this warning could result in fire, personal
injury, or death.
Never operate a furnace without a filter or with filter access
door removed.

There are no provisions for an internal filter rack in these furnaces.
An external filter rack is required.

This furnace is shipped with a factory-supplied Media Filter
Cabinet. The Media Filter Cabinet uses either a factory-supplied
standard 1-inch filter or 4-inch wide Media Filter which can be
purchased separately.

Refer to the instructions supplied with Media Cabinet for assembly
and installation options.

AIR DUCTS

General Requirements

The duct system should be designed and sized according to
accepted national standards such as those published by: Air
Conditioning Contractors Association (ACCA), Sheet Metal and
Air Conditioning Contractors National Association (SMACNA) or
American Society of Heating, Refrigerating and Air Conditioning
Engineers (ASHRAE) or consult The Air Systems Design Guide-
lines reference tables available from your local distributor. The
duct system should be sized to handle the required system design
CFM at the design external static pressure. The furnace airflow
rates are provided in Table 5-Air Delivery CFM (With Filter).

When a furnace is installed so that the supply ducts carry air
circulated by the furnace to areas outside the space containing the
furnace, the return air shall also be handled by duct(s) sealed to the
furnace casing and terminating outside the space containing the
furnace.

Secure ductwork with proper fasteners for type of ductwork used.
Seal supply- and return-duct connections to furnace with code
approved tape or duct sealer.

NOTE:

Flexible connections should be used between ductwork

and furnace to prevent transmission of vibration.

Ductwork passing through unconditioned space should be insu-
lated to enhance system performance. When air conditioning is
used, a vapor barrier is recommended.

Maintain a 1-in. clearance from combustible materials to supply air
ductwork for a distance of 36 in. horizontally from the furnace. See
NFPA 90B or local code for further requirements.

Ductwork Acoustical Treatment

NOTE:

Metal duct systems that do not have a 90 degree elbow

and 10 ft of main duct to the first branch take-off may require
internal acoustical lining. As an alternative, fibrous ductwork may
be used if constructed and installed in accordance with the latest
edition of SMACNA construction standard on fibrous glass ducts.
Both acoustical lining and fibrous ductwork shall comply with
NFPA 90B as tested by UL Standard 181 for Class 1 Rigid air
ducts.

Supply Air Connections

For a furnace not equipped with a cooling coil, the outlet duct shall
be provided with a removable access panel. This opening shall be
accessible when the furnace is installed and shall be of such a size
that the heat exchanger can be viewed for possible openings using
light assistance or a probe can be inserted for sampling the air
stream. The cover attachment shall prevent leaks.

Upflow and Horizontal Furnaces

Connect supply-air duct to flanges on furnace supply-air outlet.
Bend flange upward to 90° with wide duct pliers. (See Fig. 14.)
The supply-air duct must be connected to ONLY the furnace
supply-outlet-air duct flanges or air conditioning coil casing (when
used). DO NOT cut main furnace casing side to attach supply air
duct, humidifier, or other accessories. All accessories MUST be
connected to duct external to furnace main casing.

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Fig. 17—Typical Attic Installation

A03177

30-IN. MIN
WORK AREA

″

MIN*

TYPE-B
VENT

″

SHEET

METAL

SEDIMENT

TRAP

EQUIPMENT MANUAL

SHUT-OFF GAS VALVE

LINE CONTACT ONLY PERMISSIBLE BETWEEN
LINES FORMED BY INTERSECTIONS OF
THE TOP AND TWO SIDES OF THE FURNACE
JACKET AND BUILDING JOISTS,
STUDS, OR FRAMING.

GAS
ENTRY

″

OVER ALL

″

UNDER DOOR

″

UNDER FURNACE

EXTEND OUT 12

″

OUT

FROM FACE OF DOOR

* WHEN USED WITH
SINGLE WALL VENT
CONNECTIONS