Dunkirk Excelsior EXB Series - Manual (Page 5)

5
Direct Vent Intake Air Pipe Installation
Do not use Flexible duct for combustion air.
Outdoor air for combustion must be used.
Oil burners approved for use with outdoor air for combus-
tion are Beckett NX and Riello 40BF.
Outdoor air is obtained using the following materials/
methods.
Acceptable combustion air intake materials are listed below.
Beckett NX Burner :
• 4 inch “C” Vent (single wall galvanized).
• 4 inch Rigid Aluminum pipe (0.030” wall thickness).
Riello 40BF Burner :
• 4 inch “C” Vent (single wall galvanized).
• 4 inch Rigid Aluminum pipe (0.030” wall thickness). Use
4 inch pipe from the terminal to appliance. Reduce to 3
inch pipe to attach to burner inlet collar.
NOTICE
Seal intake pipe and fi ttings with foil tape, duct
tape, or silicone caulking and attached mechanically
with screws.
Maximum combustion air intake length is 25 feet using
eight 90° elbows. Combustion air intake does not have
minimum length.
Condensation may become a concern during some climatic
conditions. It may be necessary to wrap a portion, or
entire intake piping (particularly metal intake piping) with
waterproof insulation material.
INTAKE AIR PIPE INSTALLATION