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17
113681-01A
INSPECTING HEATER
Check pilot flame pattern and burner flame pat-
tern often.
PILOT FLAME PATTERN
Figure 24 shows a correct pilot flame pattern. Figure
25 shows an incorrect pilot flame pattern. The incor-
rect pilot flame is not touching the thermocouple.
This will cause the thermocouple to cool. When the
thermocouple cools, the heater will shut down.
If pilot flame pattern is incorrect, as shown in Fig-
ure 25
• turn heater off (see
To Turn Off Gas to Appli-
ance,
page 14 or 16, depending on your model)
• see
Troubleshooting
, page 19
Note:
The pilot flame on natural gas units will
have a slight curve, but flame should be blue and
have no yellow or orange color.
GRH/OV 008
BAD PILOT/LP
GRH/OV 007
GOOD PILOT/LP
Thermocouple
Pilot Burner
Pilot Burner
Thermocouple
Blue Flame
Yellow Flame
Figure 24 - Correct Pilot Flame Pattern
Figure 25 - Incorrect Pilot Flame Pattern
Figure 26 - Correct Burner Flame Pattern
Bad Burner Pattern-Plaque
GRH/OV 019
Figure 27 - Incorrect Burner Flame
Pattern
BURNER FLAME PATTERN
Figure 26 shows a correct burner flame pattern.
Figure 27 shows an incorrect burner flame pattern.
If burner flame pattern is incorrect, as shown in
Figure 27
• turn heater off (see
To Turn Off Gas to Appli-
ance,
page 14 or 16, depending on your model)
• see
Troubleshooting
, page 19
