![background image](http://html1.mh-extra.com/html/l-b-white/oval-u-100/oval-u-100_owners-manual-and-instructions_3274764020.webp)
Oval-U 100
Radiant Tube Heaters
www.lbwhite.com
Owner’s Manual • Oval-U 100
Radiant Tube Heaters
20
FIG. 19
Transformer
The transformer (Fig. 20) reduces the main power supply
voltage to 24 VAC. The 24 VAC is sent to the ignition
controller. Once the ignition controller receives 24 VAC, an
ignition cycle begins.
If the transformer is receiving main power voltage, but 24
VAC is absent from its output terminals, the transformer is
defective. The heater will not operate, nor will the green LED
on the burner box side be on.
FIG. 20
Ignition Control
The ignition control sends and receives voltages to
operate or verify operation of components. Refer to
the following and Fig. 21 to understand the ignition
control’s terminal designators if doing voltage checks
on the control.
L1:
Line voltage to control from power supply.
IND:
Line voltage from control to fan motor.
LED:
Connection for control’s diagnostic light wiring
harness.
MV:
24 VAC from control to gas control valve.
PS2:
24 VAC from air pressure switch back to
control
PS1:
24 VAC from control to air pressure switch.
W:
24 VAC from transformer to control. (without this
voltage the ignition control will not function)
FS:
No terminal.
R:
No terminal.
X:
No terminal.
C/COM:
Control and burner ground.
Also refer to “Operation Sequence” within this manual
as needed to understand operation of the ignition
control during a call for heat.
FIG. 21