Inspecting Heater - Desa VN18B Safety Information And Installation Manual

OpERATING HEATER
Continued
Slightly press in control knob and turn coun-
terclockwise
positions (see Figure 22 or 23).
IMPORTANT: Release downward pressure
while turning control knob. Control knob will
lock at the desired position.
Control 16,000 &
Knob 18,000 Btu/Hr
Figure 22 - Burner Patterns for Manual
Controlled Models
Control 16,000 &
Knob 18,000 Btu/Hr
Figure 23 - Burner Patterns for
Thermostat Models

INSpECTING HEATER

Check pilot flame pattern and burner flame
pattern often.
PILOT FLAME PATTERN
Figure 24 shows a correct pilot flame pattern.
Figure 25 shows an incorrect pilot flame pat-
tern. The incorrect pilot flame is not touching
the thermocouple. This will cause the thermo-
couple to cool. When the thermocouple cools,
the heater will shut down.
If pilot flame pattern is incorrect, as shown
in Figure 25
16
to the LOW, MED or HI
26,000 &
30,000 Btu/Hr
LOW
MED
HI
OFF
26,000 &
30,000 Btu/Hr
www.desatech.com
• turn heater off (see To Turn Off Gas to Ap-
pliance, page 15)
• see Troubleshooting, page 18
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.
Thermocouple
Figure 24 - Correct Pilot Flame Pattern
Thermocouple
Figure 25 - Incorrect Pilot Flame Pattern
BURNER FLAME PATTERN
Figure 26 shows a correct burner flame pat-
tern. 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 Ap-
pliance, page 15)
• see Troubleshooting, page 18
Figure 26 - Correct Burner Flame Pattern
Figure 27 - Incorrect Burner Flame
Blue Flame
Pilot Burner
Yellow Flame
Pilot Burner
Pattern
119342-01B