18
TROUBLESHOOTING INFORMATION: UNITARY DIAGNOSTIC CODES
Dia
gnos
ti
c
/Sta
tu
s
LED Code
s
ComfortNet™
T
h
ermostat Onl
y
S
y
m
p
toms of
A
b
normal
Op
eratio
n
(L
eg
a
c
y
&
ComfortNet™ T
h
ermost
at)
G
ree
n
Y
e
llo
w
R
ed
R
ed Y
1
Fa
ult
De
s
c
ription
Mess
ag
e
C
ode
Possible Cau
se
s
C
o
rrect
iv
e A
c
ti
on
s
Not
e
s
& Ca
utions
x
Int
egr
at
ed co
ntr
ol modu
le
dia
gn
ost
ic/
st
atu
s
LE
D
’s
d
is
p
lay
the
in
dic
at
ed
co
de
.
x
ComfortN
et™
th
er
most
at
dis
play
s ‘-
--‘
in
th
e
temp
er
atu
re
dis
play
ar
ea.
1 Flash
ON
OFF
ON if call
p
res
en
t;
OFF if no
call
x
Outd
oo
r
air
temp se
ns
or
faul
t.
AIR
SENS
OR
FL
T
A2
x
S
hort
ed
se
ns
or
.
x
O
pen
se
ns
or
.
x
S
ens
or
dis
co
nn
ec
ted
.
x
S
ens
or
out
of
r
a
n
g
e.
x
Ch
e
c
k
se
ns
or
c
o
nn
ec
ti
o
n
.
x
Re
p
lac
e
o
p
en
/s
ho
rt
e
d
s
e
ns
or
.
x
Tu
rn
p
o
w
e
r
OFF
pri
or t
o
re
pai
r.
x
Re
p
lac
e w
it
h
co
rr
e
c
t
re
pl
ac
e
m
en
t p
a
rt
..
x
H
eat
pum
p f
a
ils t
o
op
er
ate
in
hea
tin
g m
o
d
e
.
x
Int
egr
at
ed co
ntr
ol modu
le
dia
gn
ost
ic/
st
atu
s
LE
D
’s
d
is
p
lay
the
in
dic
at
ed
co
de
.
x
ComfortN
et™ th
er
most
at “Call fo
r
S
e
rv
ice” i
c
o
n
il
lum
inat
ed
.
x
ComfortN
et™ th
er
most
at sc
roll
s
“C
he
ck H
eat
P
u
m
p
” me
ss
ag
e.
2
Flas
he
s
ON
OFF
ON if ca
ll
p
res
en
t;
OFF if no
call
x
Outdo
or
c
o
il
temp se
ns
or
faul
t.
COIL
SENS
OR
FL
T
A3
x
S
hort
ed
se
ns
or
.
x
O
pen
se
ns
or
.
x
S
ens
or
dis
co
nn
ec
ted
.
x
S
ens
or
out
of
r
a
n
g
e.
x
Ch
e
c
k
se
ns
or
c
o
nn
ec
ti
o
n
.
x
Re
p
lac
e
o
p
en
/s
ho
rt
e
d
s
e
ns
or
.
x
Tu
rn
p
o
w
e
r
OFF
pri
or t
o
re
pai
r.
x
Re
p
lac
e w
it
h
co
rr
e
c
t
re
pl
ac
e
m
en
t p
a
rt
.
x
A
ir co
nd
iti
on
er/
h
e
at
pump
fa
ils
to
ope
ra
te.
x
Int
egr
at
ed co
ntr
ol modu
le
dia
gn
ost
ic/
st
atu
s
LE
D
’s
d
is
p
lay
the
in
dic
at
ed
co
de
.
5
Flas
he
s
ON
OFF
OFF
x
Open
fu
se
.
BL
O
W
N
FUSE
E5
x
Short
in
low
v
o
ltag
e
wi
ri
n
g
.
x
L
o
ca
te
an
d co
rr
e
c
t
sho
rt in low
v
o
ltag
e
wi
ri
n
g
.
x
Tu
rn
p
o
w
e
r
OFF
pri
or t
o
re
pai
r.
x
Repla
ce
fu
se
w
ith
3-
amp aut
omot
iv
e
ty
pe.
x
A
ir co
nd
iti
on
er/
h
e
at
pump
fa
ils
to
ope
ra
te.
x
Int
egr
at
ed co
ntr
ol modu
le
dia
gn
ost
ic/
st
atu
s
LE
D
’s
d
is
p
lay
the
in
dic
at
ed
co
de
.
6
Flas
he
s
ON
OFF
OFF
x
B
oard
mis
s-
ope
ra
tio
n.
INTERNAL
FAUL
T
EE
x
C
o
mpre
ss
or
re
lay
c
o
nt
ac
ts
w
e
ld
ed
.
x
Re
p
lac
e
co
n
tr
o
l.
x
Tu
rn
p
o
w
e
r
OFF
pri
or t
o
re
pai
r.
x
Re
p
lac
e w
it
h
co
rr
e
c
t
re
pl
ac
e
m
en
t p
a
rt
.
x
A
ir co
nd
iti
on
er/
h
e
at
pump
fa
ils
to
ope
ra
te.
x
Int
egr
at
ed co
ntr
ol modu
le
dia
gn
ost
ic/
st
atu
s
LE
D
’s
d
is
p
lay
the
in
dic
at
ed
co
de
.
x
ComfortN
et™ th
er
most
at “Call fo
r
S
e
rv
ice” i
c
o
n
il
lum
inat
ed
.
x
ComfortN
et™ th
er
most
at sc
roll
s
“C
he
ck A
ir C
o
ndi
ti
one
r”
or
“C
he
ck H
eat
P
u
m
p
” me
ss
ag
e.
7
Flas
he
s
ON
OFF
ON if ca
ll
p
res
en
t;
OFF if no
call
x
C
ircu
lat
or
blow
er mo
to
r
is n
o
t
run
ni
ng
w
hen it
s
h
ou
ld
be
run
ni
ng.
MOTOR
NOT RUN
b0
x
In
do
or
bl
o
w
e
r moto
r
pro
bl
em.
x
C
o
mmuni
cat
io
ns
err
or
betw
een
in
do
or
a
n
d
out
do
or un
it.
x
Ch
e
c
k
in
do
or
blow
er mo
to
r.
x
Ch
e
c
k
in
do
or
blow
er mo
to
r
wi
ri
n
g
.
x
Ch
e
c
k
in
do
or
un
it
con
tr
ol.
x
Re
p
a
ir
/
re
p
lac
e
any
faul
ty
w
iring.
x
Re
p
a
ir
/
re
p
lac
e
in
do
or
bl
o
w
e
r
mo
to
r or
co
nt
ro
l.
x
Tu
rn
p
o
w
e
r
OFF
pri
or t
o
re
pai
r.
x
A
p
pli
es
on
ly
to ful
ly
communicati
ng
sy
stem us
in
g
ComfortN
e
t™
the
rmos
ta
t.
x
Re
p
lac
e w
it
h
co
rr
e
c
t
re
pl
ac
e
m
en
t p
a
rt
.
x
A
ir
co
nd
iti
on
er/
h
e
at
pump
ope
ra
te
s a
t r
e
d
u
c
ed
per
form
an
ce
.
x
A
ir
co
nd
iti
on
er/
h
e
at
pump
ope
ra
tin
g
at l
o
w
st
age
w
hen
ex
pecte
d t
o
o
p
e
ra
te
at
hig
h
sta
ge.
x
Int
egr
at
ed co
ntr
ol modu
le
dia
gn
ost
ic/
st
atu
s
LE
D
’s
d
is
p
lay
the
in
dic
at
ed
co
de
.
8
Flas
he
s
ON
OFF
ON if ca
ll
p
res
en
t;
OFF if no
call
x
Airflow
is
low
er th
an
d
e
m
an
de
d.
LO
W ID
AIRFL
O
W
b9
x
In
do
or
bl
o
w
e
r moto
r
pro
bl
em.
x
B
lock
ed
fil
ter
s.
x
R
e
str
ict
iv
e/
un
der
siz
ed
duc
tw
ork.
x
In
do
or
/ o
u
td
oo
r u
n
it
miss-m
at
ch.
x
Ch
e
c
k
in
do
or
blow
er mo
to
r.
x
Ch
e
c
k
filters;
c
lea
n
/r
e
p
la
c
e as
n
e
ed
ed
.
x
Ch
e
c
k
du
ctw
o
rk
;
res
iz
e a
s
ne
ed
ed.
x
V
e
rify
indo
or
a
n
d
out
do
or un
its
ar
e
p
rop
er
ly
ma
tc
he
d.
x
Tu
rn
p
o
w
e
r
OFF
pri
or t
o
re
pai
r.
x
A
p
pli
es
on
ly
to ful
ly
communicati
ng
sy
stem us
in
g
ComfortN
e
t
the
rmos
ta
t.
x
Re
p
lac
e w
it
h
co
rr
e
c
t
re
pl
ac
e
m
en
t p
a
rt
.
x
See
s
p
e
c
if
ic
ati
on
she
et
(s)
f
o
r
air
flo
w
re
qu
ir
e
m
en
ts
an
d
max
imum ex
ternal
sta
tic
pr
es
su
re.
x
See
s
p
e
c
if
ic
ati
on
she
et
s f
o
r
ap
pr
ov
ed
sy
stem mat
ch
es.