Desa MPF18VNA Electric Heater User Manual


 
www.desatech.com
114925-01C
14
OBSERVED PROBLEM
ODS/pilot lights but flame goes
out when control knob is re
-
leased
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 for 30
seconds
3. Wait one minute for safety in
-
terlock system to reset. Repeat
ignition operation
4. Fully open equipment shutoff
valve
5. A) Contact local natural or
propane/LP gas company
B) Clean ODS/pilot (see
Cleaning and Maintenance,
page 12) 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 12) or
replace burner orifice(s)
3. Put remote selector in ON
position
4. See Wiring Diagram, page
17)
1. Contact local natural or
propane/LP gas company
2. Clean burner(s) (see Cleaning
and Maintenance, page 12)
1. Clean burner (see Cleaning
and Maintenance, page 12) or
replace burner orifice
2. Replace damaged burner
3. Replace gas regulator
4. Correct external gas regulator
pressure or replace if
defective
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,
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
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. Remote selector in OFF
position (Remote use only)
4. Wire disconnected from gas
control (Remote use only)
1. Manifold pressure is too
low
2. Burner orifice(s) clogged
1. Burner orifice is clogged or
damaged
2. Damaged burner
3. Gas appliance regulator
defective
4. External gas regulator
defective or set to incorrect
pressure
TROUBLESHOOTING
Continued