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Modulex Light Commercial Series
CHAPTER 4: Installation Instructions
OMM-0158_A
• 6/28/2022 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page
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It is not recommended to terminate vent above any door or window, as condensate can freeze
causing ice formations. Do not use a chimney as a raceway if another boiler or fireplace is vented
into or through the chimney.
Figure 4-25: Determining a Location for the Vent Outlet
Important Factors for Terminal Orientation and Location
Terminals should be positioned so as to avoid products of combustion from entering openings
into the buildings or other vents.
The terminal should be located where dispersal of combustion products is not impeded and with
due regard for the damage or discoloration that might occur to building surfaces in the vicinity. In
certain weather conditions condensation may also accumulate on the outside of the air inlet pipe.
Such conditions must be considered and where necessary insulation of the inlet pipe may be
required. In cold and/or humid weather water vapor may condense when leaving the vent terminal.
The effect of such condensation must be considered. The terminal must be located in a place not
likely to cause a nuisance.
Maintain 12” of clearance above the highest anticipated snow level or grade or whichever is
greater. Please refer to your local codes for the snow level in your area.
The whole route of the vent system must be installed upwards and never completely nor partly
downwards.
Minimum and Maximum Wall Thickness
The label at right, which is placed on the
unit, indicates the
minimum and maximum wall thickness through which
venting is allowed to penetrate
horizontally
. However, if
venting is
vertical
, then there is no minimum wall thickness.