Velocity Shadow Series, Installation And Operating Instructions Manual

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D. Design Requirements Unique to Split Vent Systems
Table 7.15 summarizes all split vent options. Illustrations of split vent systems are shown in Figure 7.14. In addition to the
requirements in Part VII-A, observe the following design requirements:
1. Permitted Terminals for Split Venting:
Rigid Vent Systems (Vent Options 25-26) – Vent terminates in a plain end (coupling for PVC). Intake terminates in a PVC 90
sweep elbow pointing down.
Use of rodent screens (not supplied) is generally recommended for both terminations. These can be fabricated from 2 x 2
(1/2” mesh) stainless steel screen. They are installed as shown in Figure 7.18.
Air Intake Terminals (Vent Options 25-26) - All split venting options shown in Tables 7.15 terminate in a PVC 90 sweep
elbow pointing down. Use of a rodent screen is generally recommended for the intake termination.
2. Vent Terminal Location – Observe the following clearances from roof mounted vent terminals (also see Figure 7.14):
• Bottom of terminal must be at least 12” above the normal snow line anticipated on the roof.
• Exhaust opening must be at least 2ft above any portion of the roof or structure located within horizontally within 10ft.
3. Horizontal Air Intake Terminal Location - Observe the following limitations on the intake terminal location (also see Figure
7.14):
• The bottom of all terminals must be at least 12” above the normal snow line. In no case should they be less than 12”
above grade level.
• If possible, install the intake terminal on a wall away from the prevailing wind. Reliable operation of this boiler cannot
be guaranteed if the intake terminal is subjected to winds in excess of 40 mph.
• Air intake terminal must not terminate in areas that might contain combustion air contaminates, such as near swimming
pools. See WARNING on page 11.
FIGURE 7.14: SPLIT RIGID VENT SYSTEM (VENT OPTIONS 25-32 - CPVC SYSTEM SHOWN IN ABOVE EXAMPLE)