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PG95ESU: Installation, Start-up, Operating and Service Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
8
Location Relative to Cooling Equipment
The cooling coil must be installed parallel with, or on the downstream
side of the unit to avoid condensation in the heat exchangers. When
installed parallel with the furnace, dampers or other flow control must
prevent chilled air from entering the 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. Refer to Installation of Evaporator Coil section for install
requirements for unshielded coils (
).
AIR FOR COMBUSTION AND VENTILATION
Introduction
2-pipe Applications
When the furnace is installed as a 2-pipe furnace, no special provisions
for air for combustion are required. However, other gas appliances
installed in the space with the furnace may require outside air for
combustion. Follow the guidelines below to ensure that other gas
appliances have sufficient air for combustion.
1-pipe Applications
When the furnace is installed as a 1-pipe furnace, it will be necessary to
ensure there is adequate air for combustion. Other gas appliances
installed with the furnace may also require air for combustion and
ventilation in addition to the amount of combustion air and ventilation
air required for the furnace. Follow the guidelines below to ensure that
the furnace and other gas appliances have sufficient air for combustion.
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 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: Current edition of Section 9.3 of the NFPA
54/ANSI Z223.1, Air for Combustion and Ventilation and applicable
provisions of the local building codes.
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. Provide TWO OUTDOOR OPENINGS, one inlet and one outlet
combustion and ventilation air opening, to the outdoors (see
).
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 (see
).
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 (see
).
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 (see
and
).
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
(see
).
b. Not less than the sum of the areas of all vent connectors in the
space.
The opening shall commence within 12 in. (300 mm) of the ceiling.
Appliances in the space shall have clearances of at least 1 in. (25 mm)
from the sides and back and 6 in. (150 mm) from the front. The opening
shall directly communicate with the outdoors or shall communicate
through a vertical or horizontal duct to the outdoors or spaces (crawl or
attic) that freely communicate with the outdoors.
WARNING
!
FIRE, INJURY OR DEATH HAZARD
Failure to follow this warning could result in personal injury, death
and/or property damage.
When the furnace is installed in a residential garage, the burners and
burner ignition devices must be located at least 18 in. (457 mm) 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 current edition of NFPA
54/ANSI Z223.1 or CAN/CSA B149.2 (see
).
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.