Space-Ray LTU 160/100-N7 Installation And Operation Instructions Manual page 50

In multiple heater applications, the combustion air intake may be ducted individually or common ducted in the
same configuration as shown for venting in Section 17.0). For combustion air intake duct sizing, please refer to
the Vent Sizing Table and use the diameter indicated, based on the number of heaters per duct.
Form #43155010
Dec 2017
All vent terminations and Combustion Air Intake Terminations must
be at least 6" higher than anticipated snow depth.
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