Air For Combustion And Ventilation; Unconfined Space - Carrier 58CVA Installation, Start-Up, Operating And Service And Maintenance Instructions

THE BLOWER IS LOCATED
TO THE RIGHT OF THE
BURNER SECTION, AND
AIR CONDITIONED AIR IS
DISCHARGED TO THE LEFT.
THE BLOWER IS
LOCATED ABOVE THE
BURNER SECTION, AND
CONDITIONED AIR IS
DISCHARGED DOWNWARD
furnace. If the dampers are manually operated, they must be
equipped with means to prevent operation of either unit unless the
damper is in the full-heat or full-cool position.

AIR FOR COMBUSTION AND VENTILATION

Provisions for adequate combustion and ventilation air must be
provided in accordance with Section 5.3 of the NFGC, Air for
Combustion and Ventilation, or applicable provisions of the local
building codes.
Canadian installations must be installed in accordance with NSC-
NGPIC Part 7 and all authorities having jurisdiction.
Fig. 6—Installation in a Garage
When the furnace is installed in a residential garage, the
burners and ignition sources must be located at least 18 inches
above the floor. The furnace must be located or protected to
avoid damage by vehicles. When the furnace is installed in a
public garage, airplane hangar, or other building having a
hazardous atmosphere, the furnace must be installed in
accordance with the National Fire Protection Association,
Inc. requirements. (See Fig. 6.)
Fig. 4—Multipoise Orientations
18-IN. MINIMUM
TO BURNERS
A93044
THE BLOWER IS
LOCATED BELOW THE
BURNER SECTION, AND
CONDITIONED AIR IS
DISCHARGED UPWARD.
OF THE BURNER SECTION,
AND CONDITIONED AIR IS
DISCHARGED TO THE RIGHT.
Air for combustion must not be contaminated by halogen
compounds, which include fluoride, chloride, bromide, and
iodide. These elements are found in aerosol sprays, deter-
gents, bleaches, cleaning solvents, salts, air fresheners, and
other household products.
All fuel-burning equipment must be supplied with air for fuel
combustion. Sufficient air must be provided to avoid negative
pressure in the equipment room or space. A positive seal must be
made between the furnace cabinet and the return-air duct to
prevent pulling air from the burner area and from blocked vent
safeguard opening.
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.
The requirements for combustion and ventilation air depend upon
whether the furnace is located in an unconfined or confined space.
Step 1—Unconfined Space
An unconfined space has a volume of at least 50 cu ft for each
1000 Btuh total input for all appliances (furnaces, clothes dryers,
water heaters, etc.) in the space.
For example:
FURNACE
INPUT (BTUH)
66,000
88,000
110,000
132,000
154,000
If the unconfined space is constructed unusually tight, air for
combustion and ventilation must come from either the outdoors or
spaces freely communicating with the outdoors. Combustion and
6
THE BLOWER IS
LOCATED TO THE LEFT
MINIMUM WITH
7–1/2 FT CEILING (SQ. FT.)
441
587
734
881
1028
A02097