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100353
TROUBLE-
SHOOTING
Continued
OBSERVED
PROBLEM
Burner backfiring
during combustion.
Yellow flame during
burner combustion.
Slight smoke or odor
during initial operation.
Burner fails to
respond to thermo-
stat.
Heater produces a
whistling noise when
burner is lit.
POSSIBLE
CAUSE
1. Burner orifice is
clogged or damaged.
2. Burner damaged.
3. Gas regulator defective.
4. Delayed ignition.
1. Not enough air.
2. Gas regulator defective.
1. Residues from manu-
facturing processes.
1. Pilot flame not lit.
2. Pilot flame not properly
heating end of thermo-
couple.
3. Pilot burner orifice
clogged or damaged.
4. Control valve defec-
tive.
5. Temperature at thermo-
stat bulb satisfied.
1. Air in gas line.
2. Air passageways on
heater blocked.
3. Dirty or partially
clogged burner orifice.
REMEDY
1. Clean burner (see Clean-
ing and Maintenance,
page 25) or replace
burner orifice.
2. Replace burner.
3. Replace control valve.
4. See above.
1. Check burner for dirt and
debris. If found, clean
burner (see Cleaning and
Maintenance, page 25.
2. Replace control valve.
1. Problem will stop after a
few hours of operation.
1. Light pilot burner (see
Lighting Instructions,
page 20).
2. Pilot flame needs adjust-
ing. Contact a qualified
service person.
3. Clean pilot burner (see
Cleaning and Mainte-
nance, page 25).
4. Replace control valve.
1. Operate burner until air is
removed from line. Have
gas line checked by local
natural gas company.
2. Observe minimum instal-
lation clearances (see
Figure 3, page 7).
3. Clean burner (see Clean-
ing and Maintenance,
page 25) or replace
burner orifice.