Lochinvar EW150 Installation & Service Manual page 23

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General venting
Combustion Air Inlet
Combustion air supply pipes can NOT be combined into a
single pipe for multiple appliance installations.
Combustion air supplied from outdoors must be free of
contaminants (See Combustion and Ventilation Air). To
prevent recirculation of flue products into the combustion
air inlet, follow all instructions in this section.
The combustion air inlet cap MUST be at least 2 feet
(61 cm) below the vertical through-roof flue outlet cap, if
within 10 feet (3.05 m).
The combustion air inlet cap and vent cap for the flue outlet
MUST be located on the same roof top surface and in the
same pressure zone.
The combustion air inlet cap must not be installed closer
than 10 feet (3.05 m) from an inside corner of a L-shaped
structure.
The combustion air inlet cap must be installed at least one
foot (30 cm) above the roof top and above normal snow
levels.
Figure 2-17 Multiple Vertical Direct Vent Installation
Multiple Vertical Direct Vent Installations
The combustion air inlet caps for multiple appliance
installations must maintain the minimum 2 foot (61 cm)
clearance below the closest vertical flue outlet if within
10 feet (3.05 m). Multiple flue outlet caps may be installed
side by side and multiple air inlet caps may be installed
side by side but the air inlet must always be at least 2 feet
(61 cm) below the closest flue outlet if the outlet is within
10 feet (3.05 m). All clearance and installation requirements
in this section and the applicable portions of the general
venting section must be maintained on multiple appliance
installations
(continued)
CAUTION
The Outdoor Vent System
Figure 2-18 Outdoor Installation
Appliances can be installed outdoors when equipped with
the optional outdoor kit. The outdoor kit includes the
outdoor vent cap / top assembly, gas valve cover, deflectors,
and a weatherproof junction box.
The bell increaser installed on the appliance vent outlet
must be removed. The bell increaser is NOT USED with
the outdoor vent cap. The outdoor vent cap /top assembly
mounts directly to the top of the appliance and covers the
flue outlet. The combustion air is provided through the
slotted openings in the jacket. The deflectors cover the
slotted openings. The appliance is self venting and requires
no additional vent piping.
The gas valve cover mounts directly to the left side panel of
the appliance and covers the gas valve and gas valve wiring
connector.
The standard junction box that is installed on the left side
panel of the appliance must be removed. The weatherproof
junction box mounts directly to the left side panel of the
appliance and provides a weatherproof enclosure for the
120 VAC service and pump connections.
NOTE
Combustion air supply must be free of contaminants (see
Combustion and Ventilation Air). To prevent recirculation
of the flue products into the combustion air inlet, follow all
instructions in this section.
Installation & Service Manual
Appliances which are shut down or will
not operate may experience freezing
due to convective air flow in the air
inlet pipe connected to the unit. Proper
freeze protection must be provided, see
Freeze Protection.
If the appliance is equipped with an
optional indoor flow switch, the flow
switch must be changed to the outdoor
version listed in the parts list.
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