Lochinvar GAS HEATER FOR COMMERICAL POOL APPLICATIONS - Manual (Page 24)

IIN NS ST TA AL LL LA AT TIIO ON N Continued
2. On horizontal runs, do not install vent pipe with seams
pointing down. Position vent pipe so that the seams are on
the top side of the vent pipe.
3. Secure all joints with a minimum of three sheet metal
screws or pop rivets. Apply aluminum foil duct tape or
silicone sealant to all screws or rivets installed in the vent
pipe.
4. Ensure that the air inlet pipes are properly supported.
ƽ
WARNING: Properly seal all joints and
seams in the inlet vent piping system. Failure to
do so may result in flue gas recirculation,
spillage of flue products, and carbon monoxide
emissions. Carbon monoxide poisoning can
cause severe personal injury or death.
Combined Combustion Air Inlet Points
You can combine the air inlet pipes from multiple pool heaters
to a single common connection if the common air inlet pipe
has a cross sectional area equal to or larger than the total area
of all air inlet pipes connected to the common air inlet pipe.
Example: Two 8" (20.3cm) air inlet pipes (50.3 in 2 [324.5cm 2 ]
area each) have a total area of 100.6 in 2 (645.2cm 2 ), requiring
a 12" (30.5cm) (113.1 in 2 [729.7cm 2 ]) common air inlet pipe.
The air inlet point for multiple pool heater air inlets must be
provided with an exterior opening which has a free area equal
to or greater than the total area of all air inlet pipes connected
to the common air inlet. This exterior opening for combustion
air must connect directly to the outdoors. The total length of
the combined air inlet pipe must not exceed a maximum of 50
(15.2m) equivalent feet. You must deduct the restriction in area
provided by any screens, grills, or louvers installed in the
common air inlet openings and some rooftop terminations.
Screens, grills, or louvers installed in the common air inlet can
reduce the free area of the opening from 25% to 75% based on
the materials used.
Vertical and Sidewall Combustion Air Inlet
IMPORTANT: To prevent recirculation of flue
products into the combustion air inlet, follow all
instructions in this section.
ƽ
WARNING: Locate and install the
combustion air inlet termination correctly.
Failure to do so can allow the discharge of flue
products to be drawn into the combustion
process. This can result in incomplete
combustion and potentially hazardous levels of
carbon monoxide in the flue products. This will
cause operational problems and the spillage of
flue products. Spillage of flue products can
cause personal injury or death due to carbon
monoxide poisoning.
You must locate the combustion air cap and the flue gas outlet
on the same rooftop surface (vertical direct vent system) or
sidewall surface (horizontal direct vent system) and in the
same pressure zone as the vent termination. Follow all
clearance requirements listed on pages 8 and 9.
Purchase and assemble the combustion air inlet cap to protect
the air inlet from wind and weather.
Alternatively, assemble the combustion air inlet cap for the
vertical rooftop air inlet from items purchased locally. The air
inlet cap consists of two 90° elbows installed to the air inlet
pipe (see Figure 26). Install the first 90° elbow on the rooftop
at the highest vertical point of the air inlet pipe. Install the
second 90° elbow on the horizontal outlet of the first elbow.
The outlet of the second 90° elbow will be pointing down. You
may use a 90° elbow and a 90° street elbow to make this
assembly. If you use a straight piece of pipe between the two
90° elbows, it should not exceed 6" (51mm) in length.
Figure 26 – Vertical Rooftop Air Inlet
For horizontal direct vent termination of combustion air, you
must use the termination cap from the pool heater
manufacturer. The sidewall air inlet cap is available as part of
a direct vent kit. See TABLE–G for Horizontal Direct Vent
Kits.
Commercial Pool Heaters
24