P/N 42-9540 11/12 Copyright 2012 Hydrotherm
Page 13
KN INSTALLATION INSTRUCTIONS FOR VENT AND AIR PIPING
Figure 8
(repeated from page 10)
Combustion air must be uncontaminated
Construction dust
: If the boiler is operated while the building
is under construction it must be protected from wood, concrete,
sheet rock and other types of dust. Failure to properly protect
the boiler from construction dust will damage the boiler.
Combustion air contaminated with fl uorocarbons or
other halogenated compounds,
such as laundry products,
cleaning solvents and refrigerants will result in the formation of
acids in the combustion chamber and vent piping. Th ese acids
will cause premature failure of the boiler and vent, causing
possible severe personal injury, death or substantial property
damage.
If the boiler room, or any room through which the air piping
travels, may contain
contaminants
as listed above, you
MUST
seal air pipe joints with silicone RTV
to prevent contaminants
from entering the boiler combustion air. Th e fi nished air piping
installation must be air-tight and water-tight.
Air piping
(see Figure 3)
8 — Air pipe connection
❑
Construct the air piping from PVC, CPVC or ABS plastic, or galvanized or
aluminum metallic pipe (including fl exible aluminum duct if desired).
When using metallic piping — seal all of the longitudinal seam joints in
addition to the component joints.
❑
Att ach the air piping to the boiler air connection, requiring use of silicone RTV
to seal the connection. If the boiler room air is free of contaminants you can use
metallic duct tape to seal the joints. With age, however, duct tape adhesives can
loosen, so duct tape is not as reliable as silicone RTV.
❑
If the installation is required to meet direct vent (sealed combustion) requirements,
seal all joints with silicone RTV. Th e air pipe installation must be air-tight and
water-tight.
❑
Th e air piping connects to the stainless steel pipe section att ached to the air intake
rain cap termination (item
10
, Figure 8). See instructions following.
❑
Maximum air 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.
9 — Supporting air piping
❑
DO NOT use the boiler air connection to support the air piping
. Provide
support straps from the ceiling or install wall brackets.
❑
Provide at least one support on all air pipe installations.
❑
Provide a support every 3 feet for air pipe lengths greater than 5 feet horizontally.
❑
Provide a support on the horizontal piping within 6 inches of every upturned
elbow to support the vertical run.
Vent and air piped through the roof
(separate terminations)
3
