L.B. White FA-MCS-D - Manual (Page 19)

Green LED on programmable controller is blinking 0.5 seconds ON, 0.5 seconds OFF Red sensor failure light is on.
Are all sensor
connect
or
s
secure and w
a
te
r
tight at
appr
opriat
e leads
in the
Smar
tBo
x
™
?
Ye
s
V
erify pr
oper connection of zone
sensor
s t
o
Smar
tBo
x
™
sensor leads.
Ensure good, tight connections, no
corr
osion, etc.
Press right sof
t k
e
y VIEW t
o
det
ermine
which sensor (T1 or T2) is inoperativ
e.
No
Problem 3
Check continuity acr
oss
sensor leads. R
eading
should be in the range of 20 k ohm. If a reading of
o
v
erload or inf
inity is
ober
v
ed, replace the
sensor
.
Heaters do not start, zone light is ON.
Is rela
y receiving
po
w
er fr
om 120
V
A
C po
w
e
r
supply?
Ye
s
Check electrical connections,
tripped cir
cuit break
er
, def
ectiv
e
wiring, etc. R
epair or replace as
needed.
No
Problem 4
Is rela
y sending
out 120 V
A
C t
o
heat
er
s?
Ensure rela
y is receiving 2
4
V
A
C
fr
om pr
ogrammable contr
oller
.
If 2
4
V
A
C is present at rela
y,
but
rela
y is no
t sending 120 V
A
C,
replace the rela
y.
If 2
4
V
A
C is no
t receiv
ed at rela
y
fr
om pr
ogrammable contr
oller
,
check wiring and connections.
If good, the pr
ogrammable
contr
oller is def
ectiv
e.
No
Ye
s
Is 120 V
A
C
deliv
ered at
heat
er
s?
Check po
w
er supply wiring ,
outlets, and electrical
connections t
o
the heat
er
.
R
epair or replace.
No
Ye
s
If 120 V
A
C is being receiv
ed
at the heat
er but heat
er is
no
t functioning, there is a
fault in the heat
er
. R
e
fer t
o
the heat
er’s Owner’s Manual
for tr
oubleshoo
ting.
Heaters do not start, zone light is OFF. Problem 5
a. V
erify t
e
m
perature cur
v
e
f
o
r
room contr
oller and
Smar
tBo
x
™
b.Ensure t
e
m
perature sensor is no
t
disabled. V
erify set-up of
te
m
perature sensor
.
Heaters start but zone light is OFF Problem 6
Zone LED is def
ectiv
e or
poor electrical connect
on
betw
een pr
ogrammable
contr
oller and LED.
V
erify 2
4
V
A
C t
o
zone LED.
If present replace LED. If
absent, repair wiring
betw
een pr
ogrammable
contr
oller and LED.
19
Ha
v
e
sensor
s
been check
ed f
o
r
continuity acr
oss
the sensor leads?
No
Ye
s
Cy
cle the po
w
er t
o
the
Smar
tBo
x
™
OFF and then
ON. If the LED remains in this blink patt
ern, replace
the pr
ogrammable contr
oller
.