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Figure 9- Horizontal Drain Length
STRAIGHT SECTIONS
VERTICAL DRAIN LENGTH (DL)
A Drain Section is used to drain water on vertical installation. It is a special
variation of an 18” pipe length with provision to drain rain or condensate
from the chimney. The pipe flue is equipped with an annular catch gutter
wall and a 1” (25) NPT nipple extending through the casing for attachment
of drain piping. See Figure 8 for details. The drain piping should include
a water leg of a height at least equal to the maximum expected operat-
ing pressure at the appliance outlet to avoid allowing flue gases to vent
through the drain. Drain Length should be installed indoors to prevent
freezing.
HORIZONTAL DRAIN LENGTH (HDL)
1. Horizontal Drain length is equipped with a 1” (25) NPT nipple, which is
attached to the inner flue and extends through the outer casing to provide a
path to drain, condensate or water from the chimney. See Figure 9.
2. A dam is attached to the inside of the inner flue adjacent to the nipple to
channel the effluent to the drain.
3. The duct drain is intended for use at the end of a horizontal run where
access and drainage is needed (see Figure 9).
4. The drain coupling must be connected to a ”P” trap or approved container
(supplied by others).
Figure 10- Variable Length (LV)
Figure 11- Detail of Variable Length
VARIABLE LENGTH (LV)
The Variable Length (LV) has one major function. It makes up odd lengths
of duct. It must not be used for expansion compensation.
It is shipped with a flanged retaining band assembly on the inner sliding
wall. See Figure 10.
The whole LV assembly includes:
• A sliding inner wall that fit closely inside a standard pipe section and it is
flanged on one side.
• An adjustable flanged retaining band, composed of;
•
Double flanged sleeve
•
Retaining flanged collar
•
An inner V-Band (BSI)
•
A different Inner Band (BS)
• Split outer casing with flanged half band on the top side only.
NOTE:
Viton® caulking must be applied on each Variable Length (LV)
and must be supplied by DuraVent. Sealant must be
ordered separately (Not included in the LV assembly).
Figure 8- Vertical Drain Length
