Carrier F96CTN, Installation, Start-Up, Operating, Service And Maintenance Instructions

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F96CTN and G96CTN (Series A): Installation, Start-up, Operating, Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
8
Ventilated Combustion Air Applications
When the furnace is installed using the ventilated combustion air option,
the attic or crawlspace must freely communicate with the outdoor to
provide sufficient air for combustion. The combustion air pipe cannot be
terminated in attics or crawlspaces that use ventilation fans designed to
operate during the heating season. If ventilation fans are present in these
areas, the combustion air pipe must terminate outdoors as a Direct Vent/
2-Pipe system.
All air for combustion is piped directly to the furnace from a space that is
well ventilated with outdoor air (such as an attic, crawl space or
equipment closet) and the space is well isolated from the living space or
garage. In addition, other gas appliances installed in the space with the
furnace may require outside air for combustion. Follow the guidelines
below to ensure that the roof or crawlspace walls have sufficient free
area to provide sufficient air for combustion and ventilation for the
furnaces. The guidelines below can be used to ensure that other gas
appliances have sufficient air for combustion.
Provisions for adequate combustion, ventilation, and dilution air must be
provided in accordance with:
• U.S.A. Installations: Section 9.3 of the current edition of NFPA
54/ANSI Z223.1, Air for Combustion and Ventilation and applicable
provisions of the local building codes.
• Canada: Part 8 of the current edition of CAN/CSA-B149.1, Venting
Systems and Air Supply for Appliances.
The requirements for combustion and ventilation air depend upon
whether or not the furnace is located in a space having a volume of at
least 50 cubic feet per 1,000 BTUh input rating for all gas appliances
installed in the space.
• Spaces having less than 50 cubic feet per 1,000 BTUh (4.8 cubic
meters per kW) require the Outdoor Combustion Air Method.
• Spaces having at least 50 cubic feet per 1,000 BTUh (4.8 cubic meters
per kW) may use the Indoor Combustion Air, Standard or Known Air
Infiltration Method.
Outdoor Combustion Air Method
1. Provide the space with sufficient air for proper combustion,
ventilation, and dilution of flue gases using permanent horizontal or
vertical duct(s) or opening(s) directly communicating with the
outdoors or spaces that freely communicate with the outdoors.
2. Fig. 6 illustrates how to provide TWO OUTDOOR OPENINGS,
one inlet and one outlet combustion and ventilation air opening, to
the outdoors.
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. 6 and Table 3 .
c. TWO HORIZONTAL DUCTS require 1 sq. in. (645 sq. mm) of
free area per 2,000 BTUh (1,100 mm2/kW) of combined input
for all gas appliances in the space per Fig. 6 and Table 3 .
d. TWO OPENINGS OR VERTICAL DUCTS require 1 sq. in.
(645 sq. mm) of free area per 4,000 BTUh (550 mm2/kW) for
combined input of all gas appliances in the space per Fig. 6 and
Table 3 .
3. ONE OUTDOOR OPENING requires:
a. 1 sq. in. (645 sq. mm) of free area per 3,000 BTUh (734
mm2/kW) for combined input of all gas appliances in the space
per Fig. 6 and Table 3 .
b. Not less than the sum of the areas of all vent connectors in the
space.
Table 3 – Minimum Free Area Required for Each Combustion Air Opening or Duct to Outdoors
* Not all families have these models.
CAUTION
!
FURNACE CORROSION HAZARD
Failure to follow this caution may result in furnace damage.
Air for combustion must not be contaminated by halogen compounds,
which include fluoride, chloride, bromide, and iodide. These elements
can corrode heat exchangers and shorten furnace life. Air contaminants
are found in aerosol sprays, detergents, bleaches, cleaning solvents,
salts, air fresheners, and other household products.
WARNING
!
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal injury or death.
The operation of exhaust fans, kitchen ventilation fans, clothes dryers,
attic exhaust fans or fireplaces could create a NEGATIVE PRESSURE
CONDITION at the furnace. Make-up air MUST be provided for the
ventilation devices, in addition to that required by the furnace. Refer to
the Carbon Monoxide Poisoning Hazard warning in the venting section
of these instructions to determine if an adequate amount of make-up air
is available.
FURNACE INPUT
(BTUH)
TWO HORIZONTAL DUCTS
(1 SQ. IN./2,000 BTUH)
(1,100 SQ. MM/KW)
SINGLE DUCT OR OPENING
(1 SQ. IN./3,000 BTUH)
(734 SQ. MM/KW)
TWO OPENINGS OR
VERTICAL DUCTS
(1 SQ. IN./4,000 BTUH)
(550 SQ. MM/KW)
Free Area of
Opening and Duct
Sq. In (Sq. mm)
Round Duct
In. (mm) Dia
Free Area of
Opening and Duct
Sq. In (Sq. mm)
Round Duct
In. (mm) Dia
Free Area of
Opening and Duct
Sq. In (mm)
Round Duct
In. (mm) Dia.
40,000* 20 (12904) 5 (127) 14 (8696) 5 (127) 10 (6452) 4 (102)
60,000
30 (19355) 6 (152) 20 (13043) 5 (127) 15 (9678) 5 (127)
80,000 40 (25807) 7 (178) 27 (17391) 6 (152) 20 (12904) 5 (127)
100,000
50 (32258) 8 (203) 34 (21739) 7 (178) 25 (16130) 6 (152)
120,000 60 (38709) 9 (229) 40 (26087) 7 (178) 30 (19355) 6 (152)
140,000*
70 (45161) 10 (254) 47 (30435) 8 (203) 35 (22581) 7 (178)