L.B. White AW250(Smart Box controller) - Manual (Page 21)

21
Problem Red LED not on during a call for heat.
Is heat
er
connect
ed t
o
its
po
w
er supply?
Connect it t
o
the
po
w
er supply
.
Ye
s
No
Ye
s
Is
pr
oper
v
oltage supplied
to
heat
er po
w
er cor
d
and thr
ough
po
w
er cor
d?
Check dataplat
e f
o
r
electrical supply
req
uirements. Pr
o
vide
pr
oper v
oltage. Check
cir
cuit break
er
s. Check
po
w
er cor
d f
or continuity
.
Is
Smar
t
Bo
x
™
calling f
or heat?
Pr
ogram the
building contr
oller
and Smar
tBo
x
™
so
bo
th are calling f
o
r
the same
te
m
perature.
No
No
No
Ye
s
Are
2
4
v
olts supplied
to
ignition
module?
P
oor electrical connection or br
ok
en wire present.
R
epair or replace.
Ye
s
LED in contr
ol module is
def
ectiv
e. R
eplace ignition
module.
Is
pr
oper
v
oltage supplied
to
transf
ormer?
Check electrical connections and po
w
er supply t
o
transf
ormer
.
R
epair as necessar
y.
No
Ye
s
Ye
s
Is
building contr
oller
calling f
or heat?
Set contr
oller t
o
call f
or heat.
No
Are 2
4
v
olts
supplied fr
om
transf
ormer?
R
eplace
transf
ormer
No
Ye
s
Heater does not cycle from minimum heat output.
Is t
e
m
perature
setting aligned
betw
een building
contr
ol and
Smar
tBo
x
™
No
Is pr
oper gas
pressure supplied
to
heat
er?
Ye
s
Pr
o
vide pr
oper
pressure t
o
heat
er and
check with a gauge.
No
Ensure t
e
m
perature
settings are aligned
betw
een the building
contr
oller and the
Smar
tBo
x
™ . R
eset if
needed.
Is v
ariable rat
e
solenoid on gas
contr
ol v
alv
e
receiving DC v
olts
fr
o
m
Smar
tBo
x
™?
No
Ye
s
Problem
Measure acr
oss t
erminals of
modulating gas contr
ol v
alv
e f
o
r
an
ywhere fr
om 1-1
5 v
olts DC.
If absent, check all wiring. If wiring is
good, the
Smar
t Bo
x
™
must be
inspect
ed f
or pr
oper operation.
Def
ectiv
e v
ariable rat
e gas contr
ol
solenoid v
alv
e. R
eplace gas
contr
ol.
Ye
s