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111487-01G
15
OPERATION
Continued
Figure 18 - Correct Pilot Flame Pattern
(Propane/LP Shown)
Thermocouple
Pilot
Burner
Pilot Burner
Thermocouple
Figure 19 - Incorrect Pilot Flame Pattern
(Propane/LP Shown)
8. Turn control knob counterclockwise
to desired heating level. The burners
should light. Set control knob to any heat
level between HI and LO.
9. To leave pilot lit and shut off burners only,
turn control knob clockwise
to the
PILOT position.
CAUTION: Do not try to ad-
just heating levels by using the
equipment shutoff valve.
TO TURN OFF GAS
TO APPLIANCE
Shutting Off Heater
1. Turn control knob clockwise
to the
OFF position.
2. Close equipment shutoff valve (see Figure
9, page 12).
THERMOSTAT CONTROL
OPERATION
The thermostat control knob can be set to any
comfort level between HI and LO. The ther-
mostat will gradually modulate the heat output
and flame height from higher to lower settings
or pilot, in order to maintain the comfort level
you select. The ideal comfort setting will vary
by household depending upon the amount of
space to be heated, the output of the central
heating system, etc.
Note: Selecting the HI setting with the control
knob will cause the burner to remain fully on,
without modulating down in most cases.
MANUAL LIGHTING
PROCEDURE
1. Follow steps 1 through 5 under
Lighting
Instructions
, page 14.
2. Press control knob and light pilot with
match.
3. Keep control knob pressed in for 30 sec-
onds after lighting pilot. After 30 seconds,
release control knob. Now follow step 8 in
Lighting Instructions
, page 14.
INSPECTING BURNERS
Check pilot flame pattern and burner flame
patterns often.
PILOT FLAME PATTERN
Figure 18 shows a correct pilot flame pattern.
Figure 19 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 19
• turn heater off (see
To Turn Off Gas to Ap-
pliance
)
• see
Troubleshooting
, page 17
Note: The correct pilot flame on natural gas
units will have a slight curve, but flame should
be blue and have no yellow or orange color.
MAIN BURNER
Periodically inspect all burner flame holes with
the heater running. All slotted burner flame
holes should be open with yellow flame pres-
ent. All round burner flame holes should be
open with a small blue flame present. Some
burner flame holes may become blocked by
debris or rust, with no flame present. If so,
turn off heater and let cool. Remove blockage.
Blocked burner flame holes will create soot.
