Air Supply For Combustion And Ventilation; Circulating Air Supply - Nordyne R4GD Series Installation Instructions Manual

AIR SUPPLY FOR COMBUSTION AND
VENTILATION
Provisions must be made in the installation of this unit to
provide an adequate supply of air for combustion. Detailed
instructions for determining the adequacy of an installation
can be found in the current revision of the National Fuel Gas
Code (ANSI Z223.1) and NFPA 54, or in Canadian installation
codes (CAN/CGA-B149), or in applicable local building
codes. Consult local codes for special requirements.
! WARNING:
Installation using methods other than those
described in the following sections must comply
with the National Fuel Gas Code and all applicable
local codes to provide sufficient combustion air
for the furnace.
If the unit is operated with inadequate combustion air
supply the flame roll-out control located above the burners
will open, turning off the gas supply to the burners. The
flame roll-out control is a manually re-setable device. DO
NOT install a jumper wire across this control to defeat its
function. DO NOT reset the control without identifying and
correcting the fault condition which caused the control to
trip. If this control must be replaced, use only the replacement
part specified in the Replacement Parts List.
Air Openings in the door of the unit, warm air registers, and
return air grilles must not be restricted.
To maximize heat exchanger life, the combustion air
must be free of chemical contaminants which form
corrosive acidic compounds when combusted. Some
examples of these chemical contaminants are chlorine,
fluorine, and sulphur. Some common sources of these
chemical contaminants are detergents, bleaches,
aerosol sprays, cleaning solvents, and a wide variety of
commercial and household products.
! WARNING:
Combustible air must not be drawn from a
contaminated atmosphere. Excessive exposure
to contaminated combustion air will result in
safety and performance related problems.
10

CIRCULATING AIR SUPPLY

WARNING:
!
Products of combustion must not be allowed to
enter the return air ductwork or the circulating
air supply. Failure to prevent products of
combustion from being circulated into the living
space can create potentially hazardous conditions
including carbon monoxide poisoning that could
result in personal injury or death.
All return ductwork must be adequately sealed,
all joints must be taped, and the ductwork must
be secured to the unit with sheet metal screws.
When return air is provided through the bottom
of the unit, the joint between the unit and the
return air plenum must be air tight.
The roof curb or cement pad on which the unit is
mounted must provide sound physical support
of the unit with no gaps, cracks, or sagging
between the unit and the curb or pad.
Return air and circulating air ductwork must not
be connected to any other heat producing device
such as a fireplace insert, stove, etc. Doing so
may result in fire, explosion, carbon monoxide
poisoning, personal injury, or property damage.
This unit is designed only for use with a supply and return
duct. Air ducts should be installed in accordance with all
applicable local codes and the standards of the National
Fire Protection Association "Standard for Installation of Air
Conditioning Systems" (NFPA 90A), and "Standard for
Installation of Residence Type Warm Air Heating and Air
Conditioning Systems" (NFPA 90B).
Design the ductwork according to methods described by
the Air Conditioning Contractors of America (ACCA) Manual
D. The ducts must be properly sized not to exceed 0.2
inches WC pressure drop at 400 scfm per nominal ton of
cooling capacity.
Ductwork should be attached directly to the unit flanges for
horizontal applications. On roof curb installations the ducts
must be attached to the curb duct supports, not the unit.