User Guide

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FIGURE 7.0 BASIC VENT OPTIONS
FIGURE 7.0a: HORIZONTAL TWIN PIPE
FIGURE 7.0b: VERTICAL TWIN PIPE
FIGURE 7.0c: SPLIT VENTING
All of these systems are considered “direct vent” because the air for combustion is drawn directly from the outdoors into the
boiler. One of the vent option columns in Tables 7.5, 7.11 or 7.15 must match the planned vent and air intake system exactly.
Design details applying to all vent systems are shown in this section. Observe all design requirements in this section, as well as
those unique to the type of system being installed:
 • B–DesignRequirementsUniquetoHorizontalTwinPipeVentSystems
 • C-DesignRequirementsUniquetoVerticalTwinPipeVentsystems
 • D-DesignRequirementsUniquetoSplitVentSystems
1. Approved Vent Systems and Materials–Thefollowingmaterialsandventsystemsmaybeusedtoventthisboiler:
• CPVC–UseonlyCPVClistedtoASTMF441.InCanada,thispipemustalsobelistedtoULCS636.
• PVC–PVCmaybeusedonlyaspermittedinthismanual.AllPVCmustbelistedtoASTMD2665.Atleast30”of
CPVC pipe, and at least one CPVC elbow, must be installed between the boiler’s vent connection and the PVC pipe. Use
of foam core PVC is not permitted for venting. PVC vent pipe may not be used to vent this boiler in Canada.
Use PVC and/or CPVC for the air intake system. PVC may be used for all air intake piping between the intake terminal and
the boiler.
When CPVC and/or PVC pipe is used, it must be joined using primer and cement that is listed for use with the pipe material
being joined (PVC, CPVC, or CPVC to PVC).