www.desatech.com
23
118621-01B
TROUbLESHOOTING
Continued
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. Thermocouple connection
loose at control valve
5. 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
6. Thermocouple damaged
7. Control valve damaged
8. Safety interlock system
has been triggered (ther-
mostat models only)
1. B u r n e r o r i f i c e ( s ) i s
clogged
2. Inlet gas pressure is too
low
1. Manifold pressure is too
low
2. B u r n e r o r i f i c e ( s ) i s
clogged
1. Burner orifice(s) is clogged
or damaged
2. Burner damaged
3. Gas regulator defective
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. Hand tighten until snug,
then tighten 1/4 turn more
5. A) Contact local natural or
propane/LP gas company
B) Clean ODS/pilot (see
Cleaning and Mainte-
nance
, page 21) or replace
ODS/pilot assembly
6. Replace pilot assembly
7. Replace control valve
8. Wait one minute for safety
interlock system to reset.
Repeat ignition operation
1. Clean burner orifice(s)
(see
Cleaning and Mainte-
nance
, page 21) or replace
burner orifice(s)
2. Contact local natural or
propane/LP gas company
1. Contact local natural or
propane/LP gas company
2. Clean burner orifice(s)
(see
Cleaning and Mainte-
nance
, page 21) or replace
burner orifice(s)
1. Clean burner orifice(s)
(see
Cleaning and Mainte-
nance
, page 21) or replace
burner orifice(s)
2. Replace burner
3. Replace gas regulator
ObSERvED PRObLEM
ODS/pilot lights but flame
goes out when control knob
is released
Burner(s) does not light after
ODS/pilot is lit
Delayed ignition of burner(s)
Burner backfiring during
combustion
