38
SERVICING
PCBJA101- PCBJA102 AIR HANDLER DIAGNOSTIC CODES
SERVICING
Co
mf
ortNet ™
Therm
ostat Onl
y
Sym
pto
ms
of Abnormal Operation
(Comm
unicating &
Non-com
mu
nicating
Therm
ostat
)
Diagnostic/Status
LED Codes
Fault Description
Message
Code
Possible Cause
s
Corrective Action
s
Notes & Caution
s
LED display is ON continuously
ON
Nor
ma
l operation
None
N
one
Norm
al operation
None
Nor
ma
l operation
Electric heaters fail to energize on a call for
W1
or Auxiliar
y/
Em
ergenc
y
heat
Integr
ated contr
ol m
od
ule LED display
provides
t
he indicated error code.
Co
mf
ortNet therm
ostat
“C
all for Service”
icon
i
llum
in
ated
Com
fortNet
t
herm
ostat scrolls “
Check Air
Handler” m
essage
1 Flash
Heater
kit selected via
dipswitches
is
t
oo large
for heater kits specified
in
s
hared data set
HTR TOO LARGE
Ec
Heater
kit selected via
dipswitches
is
t
oo large for heater
kits
i
n shared data
s
et
Verif
y
electric
h
eat dips
wi
tch
settings
Verif
y
the installed electric
heater is
valid for
the air handler.
Check na
me
plate
o
r
Specification Sheet applicable to
y
our m
odel* for allowable
h
eater
kit(
s).
Verif
y
shared data
set is correct
for the specific m
odel. Re-
populate
d
ata using co
rrect
me
mo
ry
card if required.
Turn power OFF prior to repair.
Use
me
mo
ry
card for the specific
m
odel.
Insert m
em
or
y
card BEFORE
tu
rn
ing
power ON. Me
mo
ry
card
ma
y
be rem
oved after data is
lo
ad
ed
.
Turn power OFF before rem
oving
me
mo
ry
card.
Error code w
ill be cle
ared once
data is loaded.
Electric heat airflow is higher than
expected
o
n a call for W
1 or
Auxiliary/Em
ergency heat
Integr
ated contr
ol m
od
ule LED display
provides
t
he indicated error code.
1 Flash
Heater
kit selected via
dipswitches
is
too sm
all
for heater kits specified
in
s
hared data set
HTR TOO SMALL
Ec
Heater kit selected via
dipswitches
is
too sm
all for heater
kits
i
n shared data
s
et
Verif
y
electric
heat dipsw
itch
settings
Verif
y
the installed electric
heater is
valid for
the air handler.
Check na
me
plate
or
Specification Sheet applicable to
y
our m
odel* for allowable
h
eater
kit(
s).
Verify
shared data set is correct
for the specific
mo
del. Re
-
populate
d
ata using co
rrect
me
mo
ry
card if required.
Turn power OFF prior to repair.
Use
me
mo
ry
card for the specific
m
odel.
Insert
me
mo
ry
card BEFORE
tu
rn
ing
power ON. Me
mo
ry
card
ma
y
be rem
oved after data is
lo
ad
ed
.
Turn power OFF before rem
oving
me
mo
ry
card.
Error code
wi
ll be cleared once
data is loaded.
Electric heat airflow is higher than
expected
o
n a call for W
1 or
Auxiliary/Em
ergency heat
Integr
ated contr
ol m
od
ule LED display
provides
t
he indicated error code.
1 Flash
Heater
kit selected via
dipswitches
does
n
ot
heater
k
its
s
pecified in
shared d
at
a set
NO HTR
MATCH
Ec
Heater kit selected via
dipswitches
is
doesn
’t
m
atch
heater
k
its in shared data set
Verif
y e
lectric
heat dipsw
itch
settings
Verif
y
the installed electric
heater is
valid for
the air handler.
Check na
me
plate
o
r
Specification Sheet applicable to
y
our m
odel* for allowable
h
eater
kit(
s).
Verify
shared data set is correct
for the specific m
odel. Re-
populate
d
ata using co
rrect
me
mo
ry
card if required.
Turn power OFF prior to repair.
Use
me
mo
ry
card for the specific
m
odel.
Insert m
em
or
y
card BEFORE
tu
rn
ing
power ON. Me
mo
ry
card
ma
y
be rem
oved after data is
lo
ad
ed
.
Turn power OFF before rem
oving
me
mo
ry
card.
Error code w
ill be cle
ared once
data is loaded.
No air handler operation.
Integr
ated contr
ol m
od
ule LED display
provides
t
he indicated error code.
Com
fortNet
ther
mo
stat display
s
“B
atter
y
Power”
5 Flashes
Open Fuse
Not
Displayed
Not
Displa
ye
d
Short
i
n
low
voltage wiring
Locate and correct short in low
voltage wiring
Turn power OFF prior to repair.
Replace fuse with
3
-a
mp
auto
mo
tive
t
yp
e
Air handler fails to operate
Integr
ated contr
ol m
od
ule LED display
provides
no
signal.
Co
mf
ortNet therm
ostat
“C
all for Service”
icon
i
llum
in
ated
Com
fortNet
ther
mo
stat scrolls “
Check Air
Handler” m
essage
None
No 208/230 volt power
to air
h
andler or no 24
volt power to integrated
cont
ro
l
mo
dule
Blow
n
fu
se
or circuit
breaker
Integrated control
m
odule
h
as an
i
nternal
fault.
INTERNAL
FAULT
EE
Manual disconnect switch OFF or
24
v
olt wire
i
m
prope
rl
y
connected
or loose
Blow
n fuse
o
r circuit
breaker
Integr
ated contr
ol m
od
ule has an
inte
rn
al fault
Assure 208/230 volt and 24 volt
power
to air handler and
integrated control m
odule.
Check integrated control m
odule
fuse (3A). Replace if necessary
.
Check for possible shorts in
208/230 volt and
2
4 volt circuits.
Repair as necessar
y.
Replace
bad integrated control
m
odule.
Turn power OFF prior to repair.
Replace
integrated control
m
odule f
use with 3A
auto
mo
tive
fuse.
Replace
integrated control
mo
dule with
c
orrect replace
me
nt
pa
rt
Read precautions in
“E
lectrostatic
Discharge” section of
ma
nual.