SERVICE AND TECHNICAL SUPPORT MANUAL
Gas Furnace: F9MES
Specifications subject to change without notice.
440 04 4900 02
25
Figure 16
Troubleshooting
−
Flow Chart
Is
LE
D
s
tat
us l
ig
ht
ON
s
ol
id
,
al
te
rn
atel
y
flashi
ng
bri
ght
-di
m
-b
rig
ht-
di
m
li
ke a
hea
rtb
ea
t, o
r fl
ashi
ng
ON
a
nd
O
F
F
?
Is
th
er
e 2
4V
at
2
4V
A
C
a
nd C
O
M?
Is
th
er
e
2
20V
at L1 an
d
N
E
U
T
R
A
L?
Is
th
e 2
4V
f
use
op
en
?
Is
do
or
s
w
itc
h cl
o
sed
?
R
epl
a
ce t
ra
nsf
orm
er
.
R
epl
a
ce do
or
sw
itch
.
Is
th
er
e 2
20V
goi
ng t
o s
w
itch
?
Clo
se
th
e
d
oo
r s
w
itc
h.
Is
ci
rc
ui
t
bre
ak
er cl
ose
d?
C
heck
fo
r co
nti
nui
ty
in
w
ire
from
ci
rcui
t
br
ea
ke
r to
fu
rn
ac
e.
C
lo
se
ci
rc
ui
t b
re
ak
er a
nd
go
ba
ck
to
ST
ART
.
Is
LE
D
s
tat
us l
ig
ht
al
te
rn
atel
y fl
a
shi
n
g
bri
g
ht-
di
m
-b
rig
ht-
di
m
li
ke a h
ea
rtb
eat
?
D
ete
rm
ine s
tat
us c
od
e. T
h
e st
atu
s co
d
e
is
a si
ngl
e
or
t
w
o
di
gi
tn
um
be
r
w
ith
t
he
first num
b
er det
erm
in
ed b
y
the num
b
er of
shor
t fl
ash
es a
nd
th
e se
con
d
num
be
r
afte
r
the pl
us (+
)
si
g
n,
the num
b
er
of
lo
ng
flash
es.
To
r
eca
ll a s
tat
us
c
ode
: B
rie
fly
(
2
–
3
seco
nds
) c
onn
ect
th
e
T
E
S
T
/TW
IN
term
in
al
to t
he
“C
”
the
rm
ost
at t
erm
in
al
w
ith
a j
u
m
per
w
ire t
o b
egi
n st
atu
s co
de
re
cov
er
y
an
d
com
po
nen
t t
est.
If a
pr
evi
o
us s
tat
us c
o
de i
s
pr
es
en
t, t
he
c
od
e
w
ill
re
pe
a
t 4
tim
es t
h
en
go
on t
o c
om
po
nen
t t
est.
If n
o
pre
vi
ou
s
co
d
e is p
re
se
n
t, a
co
m
p
on
en
t te
st
w
ill
begi
n w
ith
o
ut
flashi
ng an
y sta
tus cod
es
.
C
o
mpon
en
t T
e
s
t
S
e
qu
enc
e
: Gas
valv
e
an
d
h
um
id
ifie
r
w
ill n
ot
be
t
ur
ne
d o
n.
In
d
uce
r
m
oto
r w
ill sta
rt
a
nd
r
em
ai
n o
n u
nt
il
the
en
d o
f th
e bl
o
w
e
r t
est,
th
en
off.
T
he
fol
lo
w
ing c
om
po
ne
nts
ar
e o
n f
or
10
–
1
5
seco
nds
ea
ch i
ndi
vi
dual
ly
: h
ot s
ur
fac
e
igni
te
r, bl
o
w
er spe
eds
: FA
N
(if
pr
es
ent
),
HE
A
T
, COOL
.
W
as there
a p
revi
ous
stat
us c
od
e?
Go t
o s
ecti
o
n b
el
o
w
fo
r t
he fl
ash
ed
sta
tus
cod
e.
D
oes
the
co
ntr
ol
r
esp
on
d t
o
W
, Y
, a
nd
G
(24V
) t
herm
o
stat
si
g
nal
s?
R
un s
ystem
t
hr
ou
gh
a
h
eat
, o
r c
ool
in
g
cy
cl
e t
o c
heck
op
er
ati
o
n. S
tat
us c
od
es
are
er
ase
d
afte
r 8
6
hou
rs.
Is
24V
pr
es
ent
at
W
, Y
o
r G
th
erm
ost
at
term
in
al
s o
n t
he f
ur
nac
e c
ont
rol
?
C
heck
ro
om
th
erm
os
tat
or
in
ter
co
nne
cti
n
g ca
bl
e
.
Discon
nec
t all
the
th
erm
os
tat
wire
s fr
o
m
the fur
nac
e
cont
rol
.
D
oes
the
p
robl
em
r
epe
at
w
he
n u
si
ng
a
ju
m
per
w
ire
?
R
epl
a
ce f
ur
nac
e c
ont
rol
.
T
he th
erm
os
tat
is
n
ot c
om
pati
bl
e
w
ith
the
fur
nac
e co
ntr
ol
.
E
ithe
r i
nstal
l a
bal
la
st
resist
or
, co
nn
ect t
he
C
fu
rn
ace
co
ntr
ol
the
rm
osta
t te
rm
inal
to
the
th
erm
os
tat,
o
r
repl
ace
th
e t
herm
o
stat
.
YE
S
NO
YE
S
YE
S
YE
S
YE
S
Y
E
S
YE
S
YE
S
STAR
T
YE
S
YE
S
NO
NO
NO
NO
NO
NO
NO
NO
YE
S
NO
NO
Trou
bles
hoo
tin
g
Guide
R
epl
a
ce f
ur
nac
e c
ont
rol
.
YE
S
Insp
ect s
ec
ond
ar
y
vol
tag
e (
24V
)
w
iri
ng,
in
cl
udi
ng
th
erm
ost
at l
ea
ds f
or s
ho
rt
circuit
.
R
epl
a
ce f
us
e
NO
Is
LE
D
s
tat
us l
ig
ht
ON
s
ol
id
?
NO
YE
S
T
he
co
nt
ro
l is l
ock
ed
o
ut
a
n
d
w
ill
au
to
-
rese
t a
fte
r 7
2 m
inu
tes.
L
ock
out
coul
d b
e
due
to
an
y
of
th
e fol
lo
w
in
g:
-
F
la
m
e s
en
se ci
rcui
t fai
lur
e.
-
G
as
va
lv
e r
elay
st
uc
k op
en
.
-
S
oft
w
a
re che
ck
err
or.
R
eset
po
w
er
to
cl
e
ar l
ock
out.
R
e
pl
ac
e
cont
rol
if
co
de
re
pe
ats.
