L.B. White FA-MCS - Manual (Page 21)

Heater starts but heat ouptut does not change in response to
SmartBox
™
setting.
Ye
s
Problem 7
Is v
ariable rat
e
gas contr
ol v
alv
e
in heat
er
receiving 0-1
5
VDC fr
om fuse?
No
Are sensor
s
locat
ed a
w
a
y fr
om
v
entilation air
inlets?
Ensure all sensor
s are
locat
ed a
w
a
y fr
om draf
ts,
air inlets, cold spo
ts, etc.
No
Ye
s
A
. Set the
Smar
tBo
x
™
for the specif
ic heat
er
to
higher t
e
m
perature (at least 1
0F) o
v
er r
oom
te
m
perature.
B. V
erify increase in VDC t
o
gas v
alv
e.
(measure acr
oss t
erminals at v
alv
e t
o
obtain
reading) C. If no increase in VDC (should be 1
3-1
5 VDC)
at v
ariable rat
e gas contr
ol v
alv
e, then check
outputs of the
Smar
tBo
x
™
signal conditioner
s
at t
erminals 3 and 4:
-- Zone 1 conditioner: Blue wires -- Zone 2 conditioner: Br
o
wn wires
D. If 1
3-1
5 VDC is measured at output but no
t
at v
alv
e, check all wiring and t
erminals
betw
een S
m
a
rt
B
o
x
™
and v
ariable rat
e gas
contr
ol v
alv
e.
E. If no reading is giv
en at output of
Smar
tBo
x
™
then the signal conditioner f
or that
zone of heat
er
s is def
ectiv
e and must be
replaced.
Ha
v
e
the v
ariable
rat
e output fuses of the
Smar
tBo
x
™
been check
ed f
o
r
continuity?
No
Check the fuses. If def
ectiv
e, replace.
Are
Smar
tBo
x
™
sensor
s
positioned t
o
the
same height as
the r
oom contr
ol
sensor
s?
R
eposition the sensor
s. R
e
fe
r
to
sensor location
instructions in this manual.
No
Ye
s
SmartBox
™
does not
operate concurrently with room controller.
Problem 8
Check t
e
m
perature cur
v
e
f
o
r
bo
th the
Smar
tBo
x
™
and the
room contr
oller
. V
erify the
te
m
peratures match.
21