AERCO BMK 2.0 LN Dual Fuel Nov 2010 - Manual (Page 74)

TROUBLESHOOTING
8
-
10
TA
BLE 8-
1. BOILER TR
OUBLESHOOTING – Cont
inued
FA
ULT
I
NDI
CA
T
IO
N
PRO
B
A
B
LE CA
USES
T
R
OU
B
L
E
S
H
OOT
IN
G/C
OR
R
E
C
T
IV
E
A
C
T
ION
SSO
V F
A
ULT
DURING PURGE
See SSO
V SW
IT
CH O
PEN
SSO
V F
A
ULT
DURING RUN
1.
SSO
V
s
w
itc
h
c
los
ed f
o
r 15 s
e
c
onds
dur
ing r
un.
1.
Replac
e or
adj
us
t m
ic
ros
w
itc
h in SSO
V ac
tuator
. If
f
ault
per
s
is
ts
, r
eplac
e ac
tuator
.
SSO
V RELAY
FAILURE
1.
SSO
V r
e
lay
f
a
iled on boar
d.
2.
F
loating
Neutr
al.
3.
Hot and Neutr
al r
ever
s
ed at SSO
V.
1.
Pr
es
s
CLEAR button and r
es
tar
t unit. If
f
ault per
s
is
ts
, r
eplac
e
Ignition/Stepper
(
IG
S
T
) Boar
d.
2.
T
he Neutr
al and Ear
th G
round ar
e not c
onnec
ted at the s
our
c
e
and ther
ef
or
e ther
e is
a voltage m
eas
ur
ed betw
een the tw
o.
Nor
m
ally
this
m
eas
ur
em
ent s
hould be near
z
er
o or
no m
or
e than
a f
e
w
m
illivolts
.
3.
Chec
k
SSO
V pow
er
w
ir
ing.
SSO
V
SW
IT
CH O
PEN
1.
Ac
tuator
not allow
ing f
or
f
ull c
los
ur
e
of
gas
valve
2.
SSO
V pow
er
ed w
hen it s
hould not be
3.
Def
ec
tive Sw
itc
h or
Ac
tuator
4
.
In
co
rre
ct
ly
w
ire
d
sw
it
ch
.
1.
O
bs
er
v
e oper
ation of
the Saf
ety
Shut-
O
ff
Valve (
SSO
V)
thr
ough
indic
a
tor
on the Valve ac
tuator
and ens
ur
e that the valve is
f
u
lly
and not par
tially
c
los
ing.
2.
If
the SSO
V never
c
los
es
, it m
ay
be pow
er
ed c
ontinuous
ly
. Clos
e
the gas
s
upply
and r
em
ove pow
er
f
rom
the unit. Ref
er
f
ault to
qualif
ied s
e
rv
ic
e per
s
onnel.
3.
Rem
ove the elec
tr
ic
al c
over
f
rom
the SSO
V and c
hec
k
s
w
itc
h
c
ontinuity
. If
the s
w
itc
h does
not s
how
c
ontinuity
w
ith the gas
valve c
los
ed, either
adj
us
t or
r
eplac
e the s
w
itc
h or
ac
tuator
.
4.
Ens
ur
e that the SSO
V Pr
oof
of
Clos
ur
e s
w
itc
h is
c
or
rec
tly
w
ir
ed.
ST
EPPER MO
T
O
R
FAILURE
1.
Air
/F
uel
Valve out of
c
a
libr
a
tion.
2.
Air
/F
uel Valve unplugged.
3.
Loos
e w
ir
ing c
onnec
tion to the
s
tepper
m
otor
.
4.
Def
e
c
tive Air
/F
uel Valve s
tepper
mo
to
r.
5.
Def
e
c
tive Pow
e
r Supply
Boar
d or
fu
s
e
6.
Def
ec
tive IG
ST
Boar
d
1.
Ref
er
to G
F
-112 and per
for
m
Stepper
T
es
t (
par
a. 6.3.5)
to
ens
ur
e s
tepper
m
otor
r
otates
pr
oper
ly
betw
een the 0% (
fully
c
los
ed)
and 100% (
fully
open)
pos
itions
. Ver
if
y
that the VALVE
PO
SIT
IO
N
bar
gr
aph and the dial on the Air
/F
uel Valve tr
ac
k
eac
h other
to indic
ate pr
oper
oper
ation. If
oper
ation is
not
c
or
rec
t, per
for
m
the Stepper
F
eedbac
k
Calibr
ation (
G
F
-112,
par
a. 6.2.1)
.
2.
Chec
k
that the Air
/F
uel Valve is
c
onnec
ted to the Contr
ol Box
.
3.
.Ins
pec
t f
or
loos
e c
onnec
tions
betw
een the Air
/F
uel Valve m
otor
and the w
ir
ing har
nes
s
.
4.
Replac
e s
tepper
m
otor
.
5.
Chec
k
DS1 & DS2 LEDs
on Pow
er
Supply
Boar
d. If
they
ar
e not
s
teady
O
N
, r
eplac
e Pow
er
Supply
Boar
d.
6.
Chec
k
“
H
ear
tbeat”
LED DS1 and ver
if
y
it is
blink
ing O
N
& O
F
F
ever
y
s
ec
ond. If
not, r
eplac
e IG
ST
Boar
d.