CFC-E Installation Manual
Part No. 750-459 2-17
Direct Vent Combustion
If combustion air will be drawn directly from the outside by means of a duct connected to the boiler
casing, use the following as a guide:
1. Provide for adequate ventilation of the boiler room or mechanical equipment room.
2. In cold climates, to mitigate potential freeze-up of the intake pipe, it is highly recommended that a
motorized sealed damper be used to prevent the circulation of cold air through the boiler during non-
operating hours.
3. Refer to Figure 2-4 and Figure 2-6 for suggested piping of direct vent combustion installations.