Specifications
20
NBST27 Unvented Gas Log Set
In addition, periodically check the flames visually during operation.
It should just touch
the top of the thermocouple tip for natural. Refer tofor correct pilot flame.
If the pilot flame does not touch the thermocouple, then the main burner cannot function reliably.
for incorrect shape of pilot flame.
FP2272
pilot correct flame
Thermocouple for
Natural Gas
Thermocouple
for LP
FP2272
Figure 29 -
Correct Pilot Flame Appearance
FP2273
pilot bad flame
Thermocouple for
Natural Gas
Thermocouple
for LP
FP2273
Figure 30 -
Incorrect Pilot Flame Appearance
LG661
NBST log flames
In normal operation at full rate after 15 minutes, the flames
should appear as shown in Figure 31.
The flames should be yellow and extend 3-4” above the
log top surfaces. The yellow flames should not impinge
on the logs.
Figure 31 -
Correct Burner Flame Appear-
ance
LG661