American Water Heater Ultra Low NOx MODELS Installation Instructions And Use & Care Manual page 19

Burner Flames
Inspect the burner flames through the viewport. Flames
should be very small with a blue haze and small amounts
of yellow or orange at the edges. After several minutes
of operation, the burner screen may glow red. If large
flames are observed at any time, shut-off unit and call a
qualified person.
Figure 17
Flame Characteristics
Correct flame
soft blue
Water Temperature Stacking
Stacking occurs when a series of short draws of hot water
(3 gallons or less) are taken from the water heater tank.
This causes increased cycling of the burner and can result
in increased water temperatures at the hot water outlet.
This water heater's temperature control has been designed
to accurately regulate the water temperature. However,
under certain operating conditions, the water temperature
may temporarily exceed the dial setting. Consequently, in
addition to setting the temperature no higher than 120°F,
we recommend the installation of a mixing valve or an anti-
scald device in the hot water supply line or at the point of
use to further reduce the risk of scald injury. These devices
can be obtained from a plumbing service agency or your
retail supplier.
Emergency Shut Down
IMPORTANT: Should overheating occur or the gas supply
fails to shut off, turn off the water heater's manual gas
control valve and call a qualified person.
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