LAARS Pennant PNCP - Install and Operating Manual - Manual (Page 8)

LAARS Heating Systems Page 8
2.2.2 Category I Vent
When vented as a category I appliance, the vent
system must conform to the National Fuel Gas Code
(American National Standard Z223.1-Latest Edition)
in the U.S., or in Canada, to CSA B149.1 (latest
edition). The vent system must be sized and installed
for a Category I Fan-Assisted Appliance.
If chimney height is greater than 25 feet, or
if multiple units are vented into the same vertical
vent, a barometric damper must be installed on each
appliance, such that the flue draft does not exceed
(negative) 0.1" w.c.
If using a power venter for any type of Category
I venting, the draft should be set between (negative)
0.01 and 0.10" w.c.
2.2.3 Common Venting Systems
Pennant units are Category I fan-assisted when
vented vertically and adhering to all applicable codes.
Pennant units are not allowed to be vented into a
common horizontal vent system, unless a properly-
sized vent fan is used, and the common vent system
is properly designed by the vent fan manufacturer or
a qualified engineer.When common venting Pennant
fan-assisted heaters with other appliances through
one shared vertical duct called a “common vent”,
special care must be taken by the installer to ensure
safe operation. In the event that the common vent
is blocked, it is possible, especially for fan-assisted
devices, to vent backwards through non-operating
appliances sharing the vent, allowing combustion
products to infiltrate occupied spaces. If the
appliances are allowed to operate in this condition,
serious injury or death may occur.
WARNING
Operation of appliances with a blocked common
vent may lead to serious injury or death. Safety
devices must be implemented to prevent blocked
common vent operation. If safe operation of all
appliances connected to a common vent cannot
be assured, including prevention of spillage of flue
gasses into living spaces, common venting should
not be applied, and appliances should each be
vented separately.
It is for this reason that, in addition to
following proper vent sizing, construction and safety
requirements from the National Fuel Gas Code,
ANSI Z223.1 or in Canada, from CSA B149.1 as
well as all applicable local codes, it is required that
installers provide some means to prevent operation
with a blocked common vent. It is suggested that a
blocked vent safety system be employed such that if
the switch from one appliance trips due to excessive
stack spill or backpressure indicating a blocked vent
condition, that all appliances attached to the vent be
locked out and prevented from operating. (Note that
the Pennant Pool Heater is equipped with a blocked
vent safety (pressure) switch, as shipped.) As an
additional precaution, it is recommended that a Carbon
Monoxide (CO) alarm be installed in all enclosed
spaces containing combustion appliances. If assistance
is required in determining how a blocked vent safety
system should be connected to a LAARS product,
please call Applications Engineering at the telephone
number on back cover of this manual.
Refer to the installation and operating
instructions on all appliances to be common vented
for instructions, warnings, restrictions and safety
requirements. If safe operation of all appliances
connected to a common vent cannot be assured,
including prevention of spillage of flue gasses into
living spaces, common venting should not be applied,
and appliances should each be vented separately.
2.2.4 Category III Vent
When the Pennant is vented with horizontal
discharge, it must be installed per this installation
manual and the venting system manufacturer’s
installation instructions. The vent system must be
sealed stainless steel, per Table 5.
Route the vent pipe to the heater as directly as
possible. Seal all joints and provide adequate hangers
as required in the venting system manufacturer’s
Installation Instructions. Horizontal portions of the
venting system must be supported to prevent sagging
and may not have any low sections that could trap
condensate. The unit must not support the weight of
the vent pipe. Horizontal runs must slope downwards
not less than ¼ inch per foot (2 cm/m) from the unit to
the vent terminal. Reference Table 1 for the size of the
Category III vent system. Up to three elbows can be
used with 50 linear feet (15.2m) of pipe. Subtract 10
allowable linear feet (3.0m) for every additional elbow
used.
2.3 Locating Vent & Combustion Air
Terminals
2.3.1 Side Wall Vent Terminal
The Laars side wall vent hood (listed in Table
1) must be used when the heater is vented through
a side wall. It provides a means of installing vent
piping through the building wall, and must be located
in accordance with ANSI Z223.1/NFPA 54 and
applicable local codes. In Canada the installation must
be in accordance with CAN/CGA B149.1 or .2 and
TERM DESCRIPTION
Pipe Must comply with UL Standard 1738
such as Type 29-4C Stainless Steel
(either insulated or non-insulated).
Joint Follow vent manufacturer’s instructions
Sealing
Table 5. Required Horizontal Venting Material.