L.B. White Sentinel Radiant Tube AT150 40' Center Mount - Manual (Page 26)

T
w
o Times
Differential air pressure switch contacts have not closed. Indicates no air proving in fan section of heater
Is
pressure switch
stuck open? Check
continuity
.
Ye
s
No
Is
fan loose on mo
tor shaf
t?
Ye
s
Tight
en f
an blade set scre
w
Is
pr
oper
v
oltage supplied to
f
an mo
tor?
No
Ye
s
Def
ectiv
e mo
to
r.
R
eplace mo
tor
Is
ignition module receiving pr
oper
v
oltage?
No
Def
ectiv
e ignition module.
R
eplace module.
Ye
s
Def
ectiv
e wiring or
connections t
o
mo
to
r.
R
epair or replace
wiring and connections
No
Pr
o
vide pr
oper v
oltage.
Check electrical supply
,
cir
cuit break
er
s, etc.
Is
pr
oper
v
oltage supplied
to
heat
er?
Ye
s
No
Red LED Flashing One Time Differential air pessure switch contacts are closed before fan motor starts.
Is pressure switch
stuck closed?
Check continuity
.
Ye
s
No
R
eplace air
-pr
o
ving switch
Def
ectiv
e wire or loose
connection
to
air pressure switch. R
epair
as needed
Ensure copper or clear pressure switch tubes are no
t plugged or kink
ed.
Check dif
ferential air pressure orif
ices.
If plugged, clean with air pressure. Pressure switch out of calibration, replace pressure switch.
25
Is
burner bo
x
gask
eting t
orn, or
missing?
No
Ye
s
R
eplace burner bo
x
gask
eting. ensure pr
oper
sealing of all burner bo
x
com
par
tments.
No