Vanguard VGN30 Owner's Operation And Installation Manual page 19

OBSERVED
PROBLEM
Burner does not light
after ODS/pilot is lit
(continued from page
18)
Delayed ignition of
burner
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
2. Burner orifice diameter
is too small
3. Inlet gas pressure is too
low
1. Manifold pressure is too
low
2. Burner orifice
clogged
1. Burner orifice
clogged or damaged
2. Burner damaged
3. Gas regulator defective
1. Not enough air
2. Gas regulator defective
1. Residues from manu-
facturing 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
2. Replace burner orifice
3. Contact local natural gas
company
1. Contact local natural gas
company
is 2. Clean burner
CLEANING
MAINTENANCE, page
17) or replace burner ori-
fice
is 1. Clean burner
CLEANING
MAINTENANCE, page
17) or replace burner ori-
fice
2. Replace burner
3. Replace gas regulator
1. Check burner for dirt and
debris. If found, clean
burner (see CLEANING
AND MAINTENANCE,
page 17)
2. 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
natural gas company
3. Observe minimum instal-
lation clearances (see
Figure 2, page 6)
4. Clean burner
CLEANING
MAINTENANCE, page
17) or replace burner ori-
fice
Continued
(see
AND
(see
AND
(see
AND
19