UHD L
OW
P
ROFILE
D
UCT
F
URNACE
I
NSTALLATION
O
PERATION
AND
S
ERVICE
M
ANUAL
32
13.2 Troubleshooting For Automatic Ignition Burner Systems
If pro
b
lems persist, contact
Ro
b
erts-Gordon LLC at
www
.rg-inc.com
Heater Operating
TROUBLESHOOT ENDS.
N
o
Trace fa
u
lt in s
u
per
v
ision
system. See
Tro
ub
leshooting
for Flame S
u
per
v
ision
System section.
Yes
Is ignition control sho
w
ing
a "2 flashes" LED code?
N
o
Is the flame c
u
rrent at
least 1 μAmp DC
w
hen
the flame ignites?
Ignition control fa
u
lty;
replace.
See Ignition Control section.
Is ignition lead okay and
connected?
Is spark electrode okay?
Yes
Replace
v
al
v
e.
Is the gas
v
al
v
e operating?
To test
v
al
v
e, See
Tro
ub
leshooting for Gas
V
al
v
es section.
N
o
Does the flame light?
N
o
Yes
W
ait 30 - 40 seconds.
Does ignition spark
operate?
N
o
Yes
Fl
u
e
b
lo
w
er fa
u
lty;
replace
B
u
rner control fa
u
lty or
w
iring
connections fa
u
lty. Repair
or replace as re
qu
ired
Check for too m
u
ch
v
ent/air inlet d
u
ct. Check for
b
lockage in
v
ent and com
bu
stion air circ
u
it. Check for fa
u
lty air press
u
re
s
w
itch. Check press
u
re s
w
itch hoses for leaks or cracks.
Do not attempt to circ
u
m
v
ent press
u
re s
w
itch circ
u
it to
place
u
nit in operation.See Press
u
re S
w
itch section for details.
Does air press
u
re s
w
itch
change o
v
er?
N
o
Yes
Is 120
V
s
u
pply at fan
connections?
Does fl
u
e
b
lo
w
er r
u
n?
N
o
Yes
Yes
N
o
Yes
Fan and limit s
w
itch are
operating normally.
Replace temperat
u
re limit
s
w
itch.
UHD 75: Press in reset
bu
tton on man
u
al reset limit
s
w
itch. UHD 100 - 125:
W
ait
10 - 15 min
u
tes for limit
s
w
itch to cool. Does fan
stop r
u
nning?
N
o
Is ignition control sho
w
ing a
"4 flashes" LED code?
Yes
N
o
Yes
T
u
rn on controls.
Are external controls
(i.e. Thermostat) on?
N
o
Yes
T
u
rn on s
u
pplies.
Are gas & electrical
s
u
pplies on?
Yes
START
N
o
For optimum heater performance, use only replacement parts sold and supplied by Roberts-Gordon.
Conduct start-up procedure as shown
on Page 23, Section 10
.
