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113101-01E
OPERAtING HEAtER
Continued
TO TURN OFF GAS
TO AppLIANCE
1.
Turn control knob clockwise
to the
OFF position.
2. Close equipment shutoff valve (see Figure
15, page 15).
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
on page 21.
2. Depress control knob and light pilot
with match.
3. Keep control knob pressed in for 30 seconds
after lighting pilot. After 30 seconds, release
control knob. Now follow step 8 under
Lighting Instructions
, page 21.
INSPEctING bURNERS
Check pilot flame pattern and burner flame pat-
terns often.
pILOT FLAME pATTERN
Figure 30 shows a correct pilot flame pattern.
Figure 31 shows an incorrect pilot flame pat-
tern. The incorrect pilot flame is not touching the
thermocouple. This will cause the thermocouple to
cool. When the thermocouple cools, the heater will
shut down.
BURNER pRIMARY AIR HOLES
Air is drawn into the burner through the holes in
the fitting at the entrance to the burner. These holes
may become blocked with dust or lint. Periodically
inspect these holes for any blockage and clean as
necessary. Blocked air holes will create soot.
MAIN BURNER
Periodically inspect all burner flame holes with the
heater running. All slotted burner flame holes should
be open with yellow flame present. 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.
Figure 30 - Correct Pilot Flame Pattern
Figure 31 - Incorrect Pilot Flame Pattern
Pilot Burner
Thermocouple
Pilot Burner
Propane/LP
Natural Gas
Pilot Burner
Pilot Burner
Thermocouple
Propane/LP
Natural Gas
If pilot flame pattern is incorrect, as shown in
Figure 31
• turn heater off (see
To Turn Off Gas to Appli-
ance
, page 20 [manually-controlled models] or
page 22 [thermostatically-controlled model])
• see
Troubleshooting
, page 25
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.