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OWNER’S MANUAL
TROUBLESHOOTING
Continued
OBSERVED PROBLEM
Burner backfiring during
combustion
Yellow flame during burner combustion
Slight smoke or odor during initial opera-
tion
Heater produces a whistling noise when
burner is lit
POSSIBLE CAUSE
1. Burner orifice is clogged or damaged
2. Inlet gas pressure is too low
3. Burner damaged
4. Gas regulator defective
1. Not enough air
2. Inlet gas pressure is too low
3. Gas regulator defective
1. Residues from manufacturing processes
1. Turning control knob to HIGH position
when burner is cold
2. Air in gas line
3. Air passageways on heater blocked
4. Dirty or partially clogged burner orifice
REMEDY
1. Clean burner (see Cleaning and Mainte-
nance, page 11) or replace burner orifice
2. Contact local natural gas company
3. Replace burner
4. Replace gas regulator
1. Check burner for dirt and debris. If found,
clean burner (see Cleaning and Mainte-
nance, page 11)
2. Contact local natural gas company
3. Replace gas regulator
1. Problem will stop after a few hours of
operation
1. Turn control knob to LOW position and
let warm up for a minute
2. Operate burner until air is removed from
line. Have gas line checked by local natu-
ral gas company
3. Observe minimum installation clearances
(see Figure 4, page 6)
4. Clean burner (see Cleaning and Mainte-
nance, page 11) or replace burner orifice
Continued