Troubleshooting guide

PV500-23 04-2005 Section 23
6
POWER VT
®
BOILER
VENTING INSTRUCTIONS (con't)
AIR INLET DUCT OPTION
Air inlet duct is defined as a means of ducting the
outside combustion air to the burner for the
purpose of avoiding corrosion that can be caused
by contaminants which may be contained in
indoor air and/or providing sufficient fresh air for
proper combustion. If your POWER VT
®
boiler
requires an air inlet duct, it can be connected
directly to the burner inlet cap with self-tapping
screws. No additional parts are necessary.
Constructing the Air Inlet Duct
• Use 6 inch, PVC sewer and drain pipe when
constructing the combustion air duct for all
POWER VT
®
boiler models. Single-wall
galvanized may be used when PVC is not
available. Care should be taken to tape all duct
joints and connections.
When ducting vertically through a roof:
(Figure 23-4, page 8)
• The duct must be terminated with the UL listed
vent termination provided by PVI.
When ducting horizontally through a wall:
(Figure 23-5, page 8)
• The duct must extend one foot beyond the wall.
• The duct must be terminated with the UL listed
vent termination provided by PVI.
• The duct must terminate at least three feet
above grade or the level of normal snow
accumulation.
Maximum Equivalent Length of Duct
• The combustion air duct should be no more
than 100 equivalent feet in length, but it may be
of different configuration. See section on vent
system design for details concerning
combustion air duct construction.