Vanguard Heating VSGF-28PTE - Manual (Page 22)

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TROUBLESHOOTING
Continued
POSSIBLE CAUSE
1. Control knob not fully pressed in
2. Control knob not pressed in
long enough
3. Equipment shutoff valve not
fully open
4. Thermocouple connection
loose at control valve
5. Pilot flame not touching ther-
mocouple, which allows ther-
mocouple to cool, causing
pilot flame to go out. This
problem could be caused by
one or both of the following:
A) Low gas pressure
B) Dirty or partially clogged
ODS/pilot
6. Thermocouple damaged
7. Control valve damaged
8. On thermostat models, safety
interlock system has been trig-
gered
1. Burner orifice(s) clogged
2. Inlet gas pressure is too low
3. Mislocated crossover tube
1. Manifold pressure is too low
2. Burner orifice(s) clogged
3. Mislocated crossover tube
1. Burner orifice is clogged or
damaged
2. Damaged burner
3. Gas regulator defective
1. Not enough air
2. Gas regulator defective
1. Residues from manufacturing
processes and logs curing
REMEDY
1. Press in control knob fully
2. After ODS/pilot lights, keep con-
trol knob pressed in 30 seconds
3. Fully open equipment shutoff
valve
4. Hand tighten until snug, then
tighten 1/4 turn more
5. A) Contact local natural or
propane/LP gas company
B) Clean ODS/pilot (see
Cleaning and Maintenance,
page 20) or replace ODS/pilot
assembly
6. Replace pilot assembly
7. Replace control valve
8. Wait one minute for safety in-
terlock system to reset. Repeat
ignition operation
1. Clean burner(s) (see Cleaning
and Maintenance, page 20) or
replace burner orifice(s)
2. Contact local natural or pro-
pane/LP gas company
3. Contact qualified service person
1. Contact local natural or pro-
pane/LP gas company
2. Clean burner(s) (see Cleaning
and Maintenance, page 20) or
replace burner orifice(s)
3. Contact qualified service person
1. Clean burner (see Cleaning
and Maintenance, page 20)
or replace burner orifice
2. Replace damaged burner
3. Replace gas regulator
1. Check burner(s) for dirt
and debris. If found, clean
burner(s) (see Cleaning and
Maintenance, page 20)
2. Replace gas regulator
1. Problem will stop after a few
hours of operation
OBSERVED PROBLEM
ODS/pilot lights but flame
goes out when control knob is
released
One or both burners do not light
after ODS/pilot is lit
Delayed ignition of one or both
burners
Burner backfiring during com-
bustion
Yellow flame in front burner
during burner combustion
Slight smoke or odor during
initial operation