Commercial pool heaters, Iin ns st ta al ll la at tiio on n, Continued – Lochinvar GAS HEATER FOR COMMERICAL POOL APPLICATIONS User Manual
Page 12
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Combustion Air Inlet Piping
ƽ
WARNING: Locate and install the
combustion air inlet cap 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.
The sidewall or vertical rooftop DirectAire™ combustion air
supply system has specific vent material and installation
requirements. The air inlet pipe connects directly to the pool
heater to supply combustion air. In most installations, the
combustion air inlet pipe will be a dedicated system with one
air inlet pipe per pool heater. You can combine multiple air
inlets if the guidelines in Combined Air Inlet Points, page 13
are followed. The air inlet pipe will be connected to a
combustion air inlet cap as specified in this section.
For normal installations, this system uses a single-wall pipe to
supply combustion air from outdoors directly to the pool
heater.
Where overnight temperatures reach 40°F, use a Type-B
double-wall vent pipe or an insulated single-wall pipe for
combustion air. This will help prevent moisture in the cool
incoming air from condensing and leaking from the inlet pipe.
Note: When the use of the DV box adapter in the following
venting systems is not practical, contact the manufacturer for
an “in-line” filter to address problems.
Length of Air Inlet Pipe
The installed length of air inlet pipe from the pool heater to the
outside air inlet cap must not exceed 50 equivalent feet
(15.2m). Upsizing air inlet pipe diameters is permitted to meet
increased length requirements. Subtract 5 feet (1.5m) of
equivalent length for each 90° elbow. Subtract 2.5 feet (0.7m)
of equivalent length for each 45° elbow.
Do not exceed the limits for the combustion air inlet piping
lengths.
Sidewall Air Inlet
The sidewall air inlet cap is supplied in the Horizontal
DirectAire™ Vent Kit. Order the kit from the appliance
manufacturer. This sidewall cap supplies combustion air for a
single pool heater only. See TABLE–D, page 17, for kit
numbers.
Locate the pool heater as close as possible to the sidewall
where you will install the combustion air supply system.
Commercial Pool Heaters
12
Combustion Air Source
Boiler Input
Outside Air*/2 Openings
Outside Air*/1 Opening
Inside Air/2 Openings
500,000
125 in
2
(806 cm
2
)
167 in
2
(1077 cm
2
)
500 in
2
(3226 cm
2
)
650,000
163 in
2
(1052 cm
2
)
217 in
2
(1400 cm
2
)
650 in
2
(4194 cm
2
)
750,000
188 in
2
(1213 cm
2
)
250 in
2
(1613 cm
2
)
750 in
2
(4839 cm
2
)
990,000
248 in
2
(1,600cm
2
)
330 in
2
(2,129 cm
2
)
990 in
2
(6,388 cm
2
)
1,260,000
315 in
2
(2,032cm
2
)
420 in
2
(2,710 cm
2
)
1260 in
2
(8,130 cm
2
)
1,440,000
360 in
2
(2,323cm
2
)
480 in
2
(3,097 cm
2
)
1440 in
2
(9,291 cm
2
)
1,800,000
450 in
2
(2,903cm
2
)
600 in
2
(3,871 cm
2
)
1800 in
2
(11,614 cm
2
)
2,070,000
518 in
2
(3,342cm
2
)
690 in
2
(4,452 cm
2
)
2070 in
2
(13,356 cm
2
)
*Outside air openings shall directly communicate with the outdoors. When combustion air is drawn from the outside through a duct, the net free area of each of the two openings
must have twice (2 times) the free area required for Outside Air/2 Openings. The above requirements are for the boiler only, additional gas fired units in the boiler room will require
an increase in the net free area to supply adequate combustion air for all units. Combustion air requirements are based on the latest edition of the National Fuel Gas Code, ANSI
Z223.1, in Canada refer to CAN/CGA-B149 Installation Code. Check all local code requirements for combustion air.
TABLE-C
Minimum Recommended Combustion Air Supply to Mechanical Room