GMES96-U Installation Manual
6
• Seal off a non-direct vent furnace if it is installed
near an area frequently contaminated by any of the
above substances. This protects the non-direct vent
furnace from airborne contaminants. To ensure that
the enclosed non-direct vent furnace has an adequate
supply of combustion air, vent from a nearby
uncontaminated room or from outdoors. Refer to
the Combustion and Ventilation Air Requirements
for details.
• If the furnace is used in connection with a cooling coil
unit, install the furnace upstream or in parallel with the
cooling coil unit. Premature heat exchanger failure will
result if the cooling unit is placed ahead of the furnace.
For vertical (upflow) applications, the minimum
cooling coil width shall not be less than furnace width
minus 1”. Additionally, a coil installed above an
upflow furnace may be the same width as the furnace
or may be one size larger than the furnace. Example:
a “C” width coil may be installed with a “B” width
furnace.
For upflow applications, the front of the coil and
furnace must face the same direction.
• If the furnace is installed in a residential garage,
position the furnace so that the burners and ignition
source are located not less than 18" above the floor.
Protect the furnace from physical damage by vehicles.
• If the furnace is installed horizontally, ensure the access
doors are not on the “up/top” or “down/bottom” side
of the furnace.
• Do not connect this furnace to a chimney flue that
serves a separate appliance designed to burn solid
fuel.
CLEARANCES AND ACCESSIBILITY
NOTES:
• For servicing or cleaning, a 24" front clearance is
required.
• Unit connections (electrical, flue and drain) may
necessitate greater clearances than the minimum
clearances listed above.
• In all cases, accessibility clearance must take
precedence over clearances from the enclosure
where accessibility clearances are greater.
POSITION* SIDES REAR FRONT BOTTOM FLUE TOP
Upflow 0" 0" 3" C 0" 1"
Horizontal 6" 0" 3" C 0" 6"
C = If placed on combustible floor, floor MUST be wood only.
*MES96 MINIMUM CLEARANCES
TO COMBUSTIBLE MATERIALS (INCHES)
Table 1
• Centrally locate the furnace with respect to the
proposed or existing air distribution system.
• Ensure the temperature of the return air entering the
furnace is between 55°F and 100°F when the furnace is
heating.
• Provide provisions for venting combustion products
outdoors through a proper venting system. Special
consideration should be given to vent/flue pipe routing
and combustion air intake pipe when applicable. Refer
to Vent/Flue Pipe and Combustion Air Pipe -Termination
Locations for appropriate termination locations and to
determine if the piping system from furnace to
termination can be accomplished within the guidelines
given. NOTE: The length of flue and/or combustion
air piping can be a limiting factor in the location of the
furnace.
• Locate the furnace so condensate flows downwards to
the drain. Do not locate the furnace or its condensate
drainage system in any area subject to below freezing
temperatures without proper freeze protection. Refer
to Condensate Drain Lines and Trap for further details.
• Ensure adequate combustion air is available for the
furnace. Improper or insufficient combustion air can
expose building occupants to gas combustion products
that could include carbon monoxide. Refer to
Combustion and Ventilation Air Requirements.
• Set the furnace on a level floor to enable proper
condensate drainage. If the floor becomes wet or damp
at times, place the furnace above the floor on a concrete
base sized approximately 1-1/2" larger than the base
of the furnace. Refer to the Horizontal Applications
and Considerations for leveling of horizontal furnaces.
• Ensure upflow or horizontal furnaces are not installed
directly on carpeting, or any other combustible material.
The only combustible material allowed is wood.
• Exposure to contaminated combustion air will result in
safety and performance-related problems. Do not install
the furnace where the combustion air is exposed to the
following substances:
• Permanent wave solutions
• Chlorinated waxes or cleaners
• Chlorine-based swimming pool chemicals
• Carbon tetrachloride
• Water softening chemicals
• Swimming pool chemicals
• Deicing salts or chemicals
• Halogen type refrigerants
• Printing inks
• Cleaning solutions (such as perchloroethylene)
• Paint removers
• Varnishes
• Hydrochloric acid
• Cements and glues
• Antistatic fabric softeners for clothes dryers
• Masonry acid washing materials