Fedders F80A - Manual (Page 8)

7
MODEL F80A
DANGER
READ, UNDERSTAND AND FOLLOW ALL INSTRUCTIONS
IN THIS SECTION. FAILURE TO PROPERLY VENT OR
SUPPLY COMBUSTION AIR TO THIS FURNACE CAN
CAUSE CARBON MONOXIDE POISONING, OR AN
EXPLOSION OR FIRE, RESULTING IN PROPERTY DAMAGE,
PERSONAL INJURY OR LOSS OF LIFE.
WARNING
DO NOT ALLOW GAS PIPING TO BE ROUTED THROUGH
JOIST SPACES THAT ARE USED FOR RETURN AIR
PURPOSES. DO NOT USE JOIST SPACES FOR RETURN AIR
PURPOSES IF THE JOIST SPACE ALREADY CONTAINS
PLUMBING STACKS, CHIMNEY COMPONENTS, ETC.
UNLESS THE PORTION USED FOR RETURN AIR PURPOSES
CAN BE COMPLETELY ISOLATED FROM PORTIONS WITH
OTHER USAGES.
DANGER
THIS FURNACE AND ANY OTHER FUEL BURNING
APPLIANCE MUST BE PROVIDED WITH ENOUGH FRESH
AIR FOR PROPER COMBUSTION AND VENTILATION OF
THE FLUE GASES. MOST HOMES WILL REQUIRE THAT
OUTSIDE AIR BE BROUGHT TO THE FURNACE AREA.
FAILURE TO DO SO CAN CAUSE PERSONAL INJURY OR
DEATH FROM CARBON MONOXIDE POISONING.
CASE 1:
FURNACE LOCATED IN AN UNCONFINED SPACE
Unconfined space does not necessarily mean that
combustion and ventilation will not have to be introduced
from the outdoors, particularly in airtight homes. Refer to
the appropriate installation code requirements regarding
the minimum combustion air required for all fuel burning
appliances located within the unconfined area.
If the amount of combustion and ventilation air is
insufficient to properly operate the furnace and other fuel
burning appliances within the unconfined area, it will be
necessary to supply it from the outdoors based on the
criteria used when calculating the air supply for a confined
space.
NOTE: If planning to use the inside air of an unconfined
space, remember to test for proper furnace operation (as
well as other fuel burning appliances located within the
unconfined space) with respect to adequate combustion
and ventilation air with fireplace dampers open, clothes
dryer running, bathroom exhaust fans on, kitchen range
hood on, etc.
CASE 2:
FURNACE LOCATED IN A CONFINED SPACE
A confined space, (any space smaller than the minimums
discussed in CASE 1), must have two air openings one within
12 inches of the ceiling and the other within 12 inches of
the floor. The air openings must be sized based on whether
the combustion and ventilation air is being taken from
indoors or outdoors, the method outdoor air (if used) is
introduced, and taking into account any other fuel burning
appliances in the confined space.
If sufficient indoor combustion and ventilation air is
available for the furnace and all other fuel burning
appliances, even when clothes dryers, bathroom fans, range
hoods, etc. are running, size each opening according to the
appropriate installation codes.
DETERMING COMBUSTION AIR NOTE: If using grilles to cover the two openings, factor in
the free area of the grille. Typically, a grille will have a free
area approximately 50% of its nominal size. Consequently,
if the required opening is 10 inches x 10 inches , it will have
to be doubled if using a sidewall grille with 50% free area.
IMPORTANT: If an exhaust fan, fireplace, clothes dryer or
any similar device is present in the indoor area from which
the combustion and ventilation air will be drawn, negative
pressure could be a problem if natural infiltration from the
outdoors does not match the rate at which air is exhausted.
CASE 3:
FURNACE LOCATED IN A CONFINED SPACE, OUTDOOR
AIR FROM ATTIC OR CRAWL SPACE
In this circumstance, refer to the appropriate installation
code for the free area of the combustion and ventilation air
openings. If other fuel burning appliances are present, their
combustion air and ventilation air requirements must be
added to those of the furnace.
CASE 4:
FURNACE LOCATED IN A CONFINED SPACE, OUTDOOR
AIR DUCTED HORIZONTALLY
Similar to CASE 3, outdoor air for combustion and
ventilation may be drawn through horizontal ducting.
Consult the appropriate installation code for the free area
for openings. If other fuel burning appliances are present,
their combustion air and ventilation air requirements must
be added to those of the furnace.
IMPORTANT: The outdoor grilles must be installed in a
location where they will not be obstructed in any manner.
IMPORTANT: If grilles are used on the outside wall, they
must be sized properly. Most sidewall grilles have only 50%
free area, so the grill size opening must be twice the size of
the free air opening requirement.