Is LED status light on?
Is LED status light b
linking r
apidly
without a pause?
Is LED status light b
linking ON/OFF slo
wly
with a combination of shor
t and long flashes?
Deter
mine status code
.
The status code is a
2 digit n
umber with the first digit deter
mined
b
y
the n
umber of shor
t flashes and the second
digit b
y
the n
umber of long flashes?
Go to section belo
w f
or the status code that
w
as flashed.
Is there 115V at L1 and L2?
Is there 24V at SEC-1 and SEC-2?
Replace fur
nace control.
Chec
k f
or correct line v
oltage polar
ity
. If
units are twinned, chec
k f
or proper lo
w-
v
oltage (24V) tr
ansf
or
mer phasing.
T
o
recall status code br
iefly remo
v
e
and reconnect one RED wire from the
limit s
witch or flame rollout s
witch to displa
y stored status code
. On RED LED
control do not remo
v
e
po
w
er or b
lo
w
er access panel bef
ore initiating status
code recall.
Y
ou can also recall the pre
vious status code b
y
momentar
ily
shor
ting the
TEST/TWIN ter
minal to Com24V ter
minal until the LED goes out.
LED will flash the status of the pre
vious code or status code #11 (1 shor
t and
1 long flash) if there w
as no pre
vious code
. After the control repeats the code
4 times
, the control will star
t the component test sequence
. Once initiated
the control will tur
n ON at HI HEA
T speed.
The inducer will r
un f
or the entire
component test.
The HSI, b
lo
w
er motor LO HEA
T speed, HI HEA
T speed, and
COOL speed will r
un f
or 10
–
15 seconds each.
Gas v
alv
e and humidifier will
not be tur
ned on.
When the b
lo
w
er motor is tur
ned OFF the inducer will be
s
witched to lo
w-speed f
or 10 seconds
.
W
as there a pre
vious status code other
than #11?
Is door s
witch closed?
Is there 115V going to s
witch?
Replace door s
witch.
Replace tr
ansf
or
mer
.
Does the control respond to
W/W1,
W2,
Y1,
Y/Y2, and G (24V) ther
mostat signals?
Run system through a lo
w-heat, high-heat,
or cooling cycle to chec
k oper
ation.
Status
codes are er
ased after 72 hours
. On RED
LED boards stored status codes can also be
er
ased whene
ver (115V or 24V) is interr
upted.
Replace fur
nace control.
Close door s
witch and go bac
k to ST
AR
T
.
Is circuit break
er closed?
Chec
k f
or contin
uity in wire from circuit
break
er to fur
nace
.
Close circuit break
er and go bac
k to ST
AR
T
.
Chec
k room ther
mostat or
interconnecting cab
le
.
Is 24V present at
W/W1,
W2,
Y1,
Y/Y2 or G
ther
mostat ter
minals on the fur
nace control?
Disconnect all the ther
mostat wires from the
fur
nace control.
Does the prob
lem repeat when using a
jumper wire?
The ther
mostat is not compatib
le with the
fur
nace control.
Either install a ballast resistor
,
connect the Com24V ther
mostat ter
minal to
the ther
mostat, or replace the ther
mostat.
NO
YES
YES
NO
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
YES
NO
NO
NO
YES
YES
NO
NO
ST
AR
T
NO
TR
OUBLESHOO
TING GUIDE
—
TW
O-ST
A
G
E
A02189a
14
