L.B. White I-3 Infraconic - Manual (Page 21)

20
Problem 3
Inner combustion cone lights, but will not stay lit
Did y
ou
allo
w suf
ficient time
for the thermocouple
to
w
arm up?
Allo
w 30 - 60
seconds bef
ore
releasing pilo
t
butt
on. R
emo
v
e
the com
ponent and
clean It.
Ye
s
No
Ye
s
Ye
s
Check milliv
olt output of thermocouple
with milliv
olt t
est kit, 2
1
1
88. Output
should be at least 4 m
v
D.C. A reading
of less than 4 m
v
D.C. can cause inner
cone t
o
go out. If thermocouple is
w
eak, replace it. If thermocouple is
good, replace saf
ety contr
ol v
alv
e.
Is burner orif
ice
plugged?
R
eplace orif
ice.
No No
Is thermo-
couple contact nut
tight
ened securely int
o
gas contr
ol
v
alv
e?
Snug contact nut in
place. (Do no
t
o
v
er
tight
en.) Check f
o
r
debris betw
een contact
of thermocouple and
electr
omagnet of v
alv
e. Ye
s
No
Is butt
on
on saf
ety contr
ol v
alv
e
fully depressed?
Depress the butt
on on the
pilo
t saf
ety v
alv
e until gas
flo
ws thr
ough.
Ye
s
No
Is
the gas hose
par
tially
plugged?
Check gas pressure t
o
the
heat
er inlet with a gas gauge.
Pr
oper pressure at high heat
should be 5 PSIG.
Ye
s
Is pr
oper gas
pressure supplied
to
the heat
er?
No