Desa VyS18NC - Manual (Page 22)

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TROUbLESHOOTING
Continued
OBSERVED PROBLEM
ODS/pilot lights but flame
goes out when control knob
is released
Burner does not light after
ODS/pilot is lit
Delayed ignition of burner
Burner backfiring during com-
bustion
REMEDY
1. Press in control knob fully
2. After ODS/pilot lights, keep
control knob pressed in 30
seconds
3. Fully open equipment shut-
off valve
4. A) Contact local natural or
propane/LP gas company
B) Clean ODS/pilot (see
Cleaning and Maintenance,
page 19) or replace ODS/
pilot assembly
5. Hand tighten until snug,
then tighten 1/4 turn more
6. Replace pilot assembly
7. Replace control valve
1. Clean burner (see Cleaning
and Maintenance, page 19)
or replace burner orifice
2. Contact local natural or
propane/LP gas company
1. Contact local natural or
propane/LP gas company
2. Clean burner (see Cleaning
and Maintenance, page 19)
or replace burner orifice
1. Clean burner (see Cleaning
and Maintenance, page 19)
or replace burner orifice
2. Replace damaged burner
3. Replace gas regulator
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. Pilot flame not touching
thermocouple, which al-
lows thermocouple 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
5. Thermocouple connection
loose at control valve
6. Thermocouple damaged
7. Control valve damaged
1. Burner orifice clogged
2. Inlet gas pressure is too
low
1. Manifold pressure is too
low
2. Burner orifice clogged
1. Burner orifice is clogged or
damaged
2. Damaged burner
3. Gas regulator defective