Desa H18N Owner's Operation And Installation Manual page 29

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 one or
both burners
Burner backfiring during
combustion
110399-01J
TROUBLESHOOTING
Continued
POSSIBLE CAUSE
1. Control knob not fully
pressed in
2. Control knob not pressed in
long enough
3. Safety interlock system has
been triggered
4. Equipment shutoff valve not
fully open
5. Pilot flame not touching
thermocouple, which allows
thermocouple to cool, caus-
ing 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 connection
loose at control valve
7. Thermocouple damaged
8. Control valve damaged
1. Inlet gas pressure is too
low
2. Burner orifice(s) clogged
3. Thermopile leads discon-
nected or improperly con-
nected (Remote-Ready
Models Only)
4. Burners will not come on in
remote position (Remote-
Ready Models Only)
1. Manifold pressure is too
low
2. Burner orifice(s) clogged
1. Burner orifice is clogged or
damaged
2. Damaged burner
3. Gas regulator defective
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REMEDY
1. Press in control knob fully
2. After ODS/pilot lights, keep
control knob pressed in 30
seconds
3. Wait one minute for safety
interlock system to reset.
Repeat ignition operation
4. Fully open equipment shut-
off valve
5. A) Contact local natural or
propane/LP gas company
B) Clean ODS/pilot (see
Cleaning and Maintenance,
page 27) or replace ODS/
pilot assembly
6. Hand tighten until snug,
then tighten 1/4 turn more
7. Replace pilot assembly
8. Replace control valve
1. Contact local natural or
propane/LP gas company
2. Clean burner(s) (see Cleaning
and Maintenance, page 27)
or replace burner orifice(s)
3. Reconnect leads (see Wir-
ing Diagram, page 28)
4. Replace battery in transmit-
ter and receiver
1. Contact local natural or
propane/LP gas company
2. Clean burner(s) (see Cleaning
and Maintenance, page 27)
or replace burner orifice(s)
1. Clean burner (see Cleaning
and Maintenance, page 27)
or replace burner orifice
2. Replace damaged burner
3. Replace gas regulator
29