www.desatech.com
111986-01F
34
OBSERVED PROBLEM
Pilot lights but flame goes
out when control knob is
released
Burner does not light after
pilot is lit
Delayed ignition burner
Burner backfiring during com
-
bustion
Slight smoke or odor during
initial operation
POSSIBLE CAUSE
1. Gas control knob not fully
pressed in
2. Gas 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
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
3. Thermopile leads discon
-
nected or improperly con
-
nected
4. Thermopile is defective
1. Manifold pressure is too
low
2. Burner porting or orifice
clogged
1. Burner orifice is clogged or
damaged
2. Damaged burner
3. Gas regulator defective
1. Residues from manufac
-
turing processes and logs
curing
REMEDY
1. Press in gas control knob
fully
2. After pilot lights, keep gas
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 pilot (see
Cleaning
and Maintenance
, page 31)
or replace 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 31)
or replace burner orifice
2. Contact local propane/LP or
natural gas company
3. Reconnect leads
4. Replace thermopile
1. Contact local propane/LP or
natural gas company
2. Clean burner (see
Cleaning
and Maintenance
, page 31)
or replace burner orifice
1. Clean burner (see
Cleaning
and Maintenance
, page 31)
or replace burner orifice
2. Replace damaged burner
3. Replace gas control
1. Problem will stop after a few
hours of operation
TROUbLESHOOTING
Continued