P/N 42-9540 11/12 Copyright 2012 Hydrotherm
Page 16
KN INSTALLATION INSTRUCTIONS FOR VENT AND AIR PIPING
Vent piped through a side wall
(combustion air from the boiler room)
(cont.)
4
❑
Slope horizontal runs toward the boiler
. All horizontal runs of vent pipe
must slope continuously at least 1/4 inch per foot
(21 mm per meter)
to ensure
condensate drains completely back to the boiler. DO NOT install the vent piping
with any sections that could trap condensate.
2 — Vent piping components
❑
See Table 4 for acceptable vent components.
NO OTHER
vent materials are
acceptable.
❑
Carefully follow the instructions supplied by the vent piping manufacturer.
❑
Th e vent joints seal with elastomer rings in the pipe and fi tt ings. Avoid damaging
these seals.
❑
Adjustable lengths of EZ-Seal pipe
— Length adjustments with EZ-Seal piping
are done with slip-fi t adjustable length sections, not by cutt ing the pipe. Make sure
the adjustable length does not jut into elbows or terminations. Th is could block
fl ue gas and condensate fl ow.
❑
Maximum vent piping length
— See the table in Figure 8 for the maximum
allowable length. Each elbow causes the same pressure drop as 10 feet of vent pipe,
so the allowable length reduces 10 feet for each elbow used in the piping. When
45° elbows are used, two 45° elbows are equivalent to one 90° elbow.
❑
Insulate the vent piping where it passes through unheated areas
to prevent
condensate freeze-up. Do not insulate the within 18 inches of the termination
when it passes through a combustible wall.
❑
If the pipe passes through an occupied space, install a chase around the pipe,
following the vent pipe instructions and applicable codes.
❑
Clearance from combustible materials
— Provide minimum clearance to all
combustible materials of at least 2 inches
(51 mm)
.
3 & 4 — Support the vent piping completely
❑
DO NOT use the boiler vent connection to support the vent piping
. Provide
support straps from the ceiling and pedestal supports from the fl oor; utilize
noncombustible saddle. Th is is required on ALL installations, regardless of the
length of the horizontal piping connected to the boiler.
❑
Install at least one support on every horizontal run
. For horizontal runs
longer than 5 feet
(1.5 m)
, install a support every 3 feet
(0.9 m)
.
❑
Vent piping cannot be supported from above (such as relying on roof jack sections).
You must install supports on the horizontal piping before the vent turns upward.
Provide a support on the horizontal piping
within 6 inches of every upturned
elbow
to support the vertical run.
❑
Follow the vent pipe manufacturer’s instructions for placement and installation of
supports.
❑
Follow applicable codes and the vent pipe instructions to install fi re stops, thimbles
or other devices at all fl oor and wall penetrations.
❑
Provide minimum 2 inches
(51 mm)
clearance to all combustible construction.
continued on next page
