UHA S
TANDARD
U
NIT
H
EATER
I
NSTALLATION
O
PERATION
AND
S
ERVICE
M
ANUAL
38 of 51
14.3 Troubleshootin
g
for Flame Supervision System
NOTE:
Minim
u
m flame probe c
u
rrent 1 μA DC. Typical flame probe c
u
rrent 3-5 μA DC.
Repair or replace as
re
q
uired.
If pro
b
lems persist, contact
Ro
b
erts-Gordon LLC at
www.rg-inc.com
Replace ignition control.
Use General
Trou
b
leshooting section to
trace the fault.
Heater Operating
TROUBLESHOOT ENDS.
N
o
Repair or replace as
re
q
uired.
Is inlet
b
urner gas pressure
correct? Is li
v
e and neutral
polarity correct? Is
flame pro
b
e circuit correct?
Is there a current flowing in
the flame pro
b
e circuit with
no flame present?
Yes
N
o
Does “lockout” occur when
there is a flame present?
Yes
Is the connecting lead
damaged? Is the flame pro
b
e
damaged or touching earthed
components?
N
o
Is the flame present and
at least 1
μ
A DC flame
current?
Connect a DC ammeter in
series with the flame pro
b
e.
Yes
N
o
Yes
Yes
N
o
START
To meas
u
re flame c
u
rrent, connect a 0 - 50 μA DC meter in series
w
ith the flame probe. If the meter
reads negative val
u
es, then reverse the test leads.
