Desa CGN20 - Manual (Page 12)

12 103568
VENT-FREE NATURAL GAS HEATERS
BLUE-FLAME CGN20, CGN20L AND RN30D
OBSERVED PROBLEM
When ignitor button is pressed, there is no
spark at ODS/pilot
When ignitor button is pressed, there is
spark at ODS/pilot but no ignition
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
TROUBLESHOOTING
WARNING: Turn off and un-
plug heater and let cool before
servicing. Only a qualified ser-
vice person should service and
repair heater.
Note: All troubleshooting items are listed
in order of operation.
CAUTION: Never use a wire,
needle, or similar object to clean
ODS/pilot. This can damage ODS/
pilot unit.
POSSIBLE CAUSE
1. Ignitor electrode positioned wrong
2. Ignitor electrode broken
3. Ignitor electrode not connected to
ignitor cable
4. Ignitor cable pinched or wet
5. Broken ignitor cable
6. Bad piezo ignitor
1. Gas supply turned off or manual shutoff
valve closed
2. Control knob not in PILOT position
3. Control knob not pressed in while in
PILOT position
4. Air in gas lines when installed
5. ODS/pilot is clogged
6. Gas regulator setting is not correct
1. Control knob not fully pressed in
2. Control knob not pressed in long enough
3. Manual shutoff valve not fully open
4. Thermocouple connection loose at con-
trol valve
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 damaged
7. Control valve damaged
1. Burner orifice is clogged
2. Burner orifice diameter is too small
3. Inlet gas pressure is too low
1. Manifold pressure is too low
2. Burner orifice is clogged
3. Inlet gas pressure is too low
REMEDY
1. Replace ignitor
2. Replace ignitor
3. Reconnect ignitor cable
4. Free ignitor cable if pinched by any metal
or tubing. Keep ignitor cable dry
5. Replace ignitor cable
6. Replace piezo ignitor
1. Turn on gas supply or open manual shutoff
valve
2. Turn control knob to PILOT position
3. Press in control knob while in PILOT
position
4. Continue holding down control knob.
Repeat igniting operation until air is re-
moved
5. Clean ODS/pilot (see Cleaning and Main-
tenance, page 11) or replace ODS/pilot
assembly
6. Replace gas regulator
1. Press in control knob fully
2. After ODS/pilot lights, keep control knob
pressed in 30 seconds
3. Fully open manual shut-off valve
4. Hand tighten until snug, then tighten 1/4
turn more
5. A) Contact local natural gas company
B) Clean ODS/pilot (see Cleaning and
Maintenance, page 11) or replace ODS/
pilot assembly
6. Replace thermocouple
7. Replace control valve
1. Clean burner (see Cleaning and Mainte-
nance, page 11) or replace burner orifice
2. Replace burner orifice
3. Contact local natural gas company
1. Co. natural gas company
2. Clean burner (see Cleaning and Mainte-
nance, page 11) or replace burner orifice
3. Contact local natural gas company