T
ROUBLESHOOTING
C
HART
54
Co
m
fo
r
tNet™
Therm
ost
a
t On
ly
Sym
ptom
s of A
bnor
m
a
l Opera
ti
on
(Leg
ac
y &
C
o
m
fort
N
et™ Therm
o
st
at)
D
ia
g
no
st
ic
/St
a
tus
LED Codes
Fault De
scr
ipt
ion
Messa
ge
Code
P
o
ss
ib
le C
a
u
se
s
Correct
ive Action
s
No
tes
& Ca
utio
ns
x
Ci
rcu
lato
r
b
lo
w
er ru
ns
cont
inu
o
u
sl
y
. No
fur
n
ace opera
tion.
x
Int
egr
ate
d c
o
ntr
o
l m
o
du
le L
E
D
di
sp
lay
p
rovi
des
E3
err
o
r
code.
x
Com
fortNet™ therm
o
st
at
“
C
all for
Service” ic
on illum
inate
d.
x
Com
fortNet™ therm
os
ta
t scr
o
lls “
C
heck
Fur
nace” m
essa
ge.
E3
x
Prim
ary
li
m
it or
au
xi
li
ary
lim
it circu
it
is
op
en.
x
Ro
llo
ut
li
m
it
ci
rcui
t
is
op
en.
HIGH
LIMIT
OPEN
E3
x
In
su
ffi
ci
en
t con
d
itio
ned
ai
r ov
er
th
e
h
eat
ex
ch
an
g
er
. B
loc
ke
d
filter
s, re
str
ic
tive
duc
twor
k
,
im
proper
ci
rc
u
lat
or b
low
er sp
ee
d,
or fa
ile
d c
irc
ul
at
or b
low
er m
o
tor.
x
Flam
e rollout.
x
Mis
al
igne
d
bur
ner
s,
b
loc
ke
d f
lue
an
d/
or a
ir i
n
le
t
pi
pe,
or fa
ile
d
in
d
u
ce
d dr
aft
bl
ow
er.
x
Loose or im
properly
conne
cte
d
w
iri
ng.
x
Chec
k
f
il
ter
s an
d
duc
tw
or
k fo
r
bl
oc
ka
ge.
Cle
an f
il
te
rs or
rem
ove ob
st
ru
ct
io
n.
x
Ch
eck
ci
rcu
lato
r blower s
p
eed
an
d per
form
ance. Correct
spee
d
or re
place blower m
o
tor
if
nece
ss
ary
.
x
Chec
k b
u
rn
er
s f
o
r pr
op
er
al
ign
m
en
t.
x
Chec
k
f
lue a
n
d ai
r i
n
le
t p
ipi
ng
fo
r blo
ck
ag
e, p
rop
er leng
th
,
elb
ow
s, a
n
d te
rm
inati
on. C
o
rrec
t
as nece
ssa
ry
.
x
Chec
k i
n
du
ce
d dra
ft
bl
ow
er f
o
r
prope
r per
form
ance. Replace
if
nece
ss
ary
.
x
Tighte
n
or c
o
rrec
t wiring
co
nne
ct
ion.
x
T
u
rn
pow
er
O
F
F pr
io
r to
repa
ir.
x
See Spe
cif
ica
ti
o
n
S
h
ee
t
ap
pl
ica
bl
e t
o
y
o
ur m
o
del
for a
llowa
ble r
ise ra
nge
an
d pr
o
p
er c
irc
ula
to
r
spe
ed.
x
See
"V
en
t/F
lue P
ipe
"
se
ct
ion
fo
r p
ipi
ng
d
etai
ls
.
x
Ind
u
ce
d draf
t
b
low
er an
d
cir
cu
la
tor b
low
er
ru
ns
co
nti
nuo
usl
y
.
N
o
fu
rn
ace op
erati
on
.
x
Int
egr
ate
d c
o
ntr
o
l m
o
du
le L
E
D
di
sp
lay
p
rovi
des
E4
err
o
r
code.
x
Com
fortNet™ therm
o
st
at
“
C
all for
Service” ic
on illum
inate
d.
x
Com
fortNet™ therm
os
ta
t scr
o
lls “
C
heck
Fur
nace” m
essa
ge.
E4
x
Flam
e sensed with no
call for
hea
t.
IMPROPE
R
FLAME
E4
x
Sh
ort
t
o
g
ro
u
nd
in
fl
ame s
en
se
circ
uit.
x
Linger
ing bur
ner f
la
m
e.
x
Slow
c
lo
sin
g g
as
va
lv
e.
x
Corre
ct
shor
t at f
lam
e sens
or or
in f
lam
e sensor wiring.
x
Chec
k f
o
r linger
ing f
la
m
e.
x
Veri
fy
p
rop
er op
eratio
n
o
f gas
val
v
e.
x
T
u
rn
pow
er
O
F
F pr
io
r to
repa
ir.
x
No fur
n
ac
e opera
tion.
x
Int
egr
ate
d c
o
ntr
o
l m
o
du
le L
E
D
di
sp
lay
p
rovi
des
E5
err
o
r
code.
x
Com
fortNet™ therm
os
ta
t dis
p
lay
s
“B
attery
Power”.
E5
x
Op
en
Fus
e
No
t
Di
sp
la
y
ed
No
t
Disp
la
y
ed
x
Sho
rt in low
vo
lt
ag
e
w
iri
ng
x
Locate
and
co
rre
ct short in low
v
o
lt
age wi
ri
ng
x
T
u
rn
pow
er
O
F
F pr
io
r to
repa
ir.
x
Replace f
u
se with
3-a
m
p
aut
o
m
o
ti
ve ty
pe
x
Norm
al furna
ce oper
ation.
x
Int
egr
ate
d c
o
ntr
o
l m
o
du
le L
E
D
di
sp
lay
p
rovi
des
E6
err
o
r
code.
E6
x
Flam
e sens
e m
icro am
p
si
g
n
al is low
WE
A
K
FLAME
E6
x
Flam
e sens
or
is c
o
at
ed
/o
xi
di
ze
d.
x
Flam
e sens
or
inc
o
rr
ec
tly
po
si
ti
o
n
ed
i
n
bur
n
er f
lam
e.
x
Lazy
burner f
lam
e due to
im
proper
ga
s pr
es
su
re
or
com
bus
tion air.
x
Sand flam
e sensor if
co
at
ed
/ox
id
ized
.
x
In
sp
ect
fo
r prop
er
se
ns
o
r
al
ign
m
en
t.
x
Ch
eck
inl
et
ai
r p
ipi
ng
fo
r
bl
oc
ka
ge,
pr
o
p
er
len
g
th,
e
lb
o
w
s,
an
d term
ina
ti
o
n
.
x
Com
p
are curr
ent gas
pre
ss
ure
to
rati
ng
pl
at
e. Ad
jus
t as
n
eed
ed
.
x
T
u
rn
pow
er
O
F
F pr
io
r to
repa
ir.
x
Sand flam
e sensor with
e
m
ery cloth.
x
See "
V
ent/
Flu
e Pi
pe"
se
ct
ion
fo
r p
ipi
ng
d
etai
ls
.
x
See
rat
ing pl
ate
fo
r pr
op
er
gas pre
ssur
e.
x
Fur
nace
fa
ils to opera
te.
x
Int
egr
ate
d c
o
ntr
o
l m
o
du
le L
E
D
di
sp
lay
p
rovi
des
E7
err
o
r
code.
x
Com
fortNet™ therm
o
st
at
“
C
all for
Service” ic
on illum
inate
d.
x
Com
fortNet™ therm
os
ta
t scr
o
lls “
C
heck
Fur
nace” m
essa
ge.
E7
x
Pro
b
lem
w
ith
ig
ni
ter
circ
uit.
IGNITER
FAULT
E7
x
Im
pro
p
er
ly
conne
cte
d i
g
n
iter.
x
Sho
rte
d
ig
ni
ter.
x
Po
or un
it
groun
d
.
x
Ign
iter re
lay
faul
t o
n
in
te
gra
te
d
co
ntr
o
l m
odule.
x
Chec
k a
nd c
o
rr
ect w
irin
g fr
om
in
te
gra
te
d
co
n
tro
l m
odu
le
to
ig
n
iter.
x
Repl
ace s
h
o
rt
ed
ig
niter.
x
Ch
eck
an
d
co
rrect
uni
t
g
round
wi
ri
n
g
.
x
Ch
eck
ign
it
er o
u
tp
ut
fro
m
contr
o
l. Replace
if necessary
.
x
T
u
rn
pow
er
O
F
F pr
io
r to
repa
ir.
x
Replace ignite
r
with
corre
ct re
placem
ent
part.
x
Replace c
o
ntr
o
l with
corre
ct re
placem
ent
part.
