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Guardian 2.0 LP or Natural Gas Heater
www.lbwhite.com
Owner’s Manual • Guardian 2.0
18
Igniter/Flame Sensor
(Spark - AD Models)
Refer to Fig. 18 for servicing of the igniter/flame
sensor.
• The igniter / flame sensor may require cleaning
due to accumulations of dust and dirt over a
period of time, affecting its ability to ignite fuel gas
and sense burner flame. Cleaning will require
igniter/sensor removal.
-- If the sparks appear strong but the heater cycles
off, take the igniter out and clean the rods with
either an emery cloth or a steel wool to remove
any buildup.
-- If the sparks appear weak, remove the igniter and
ensure the igniter gap is 1/8-3/16 in.
-- Inspect the igniter’s insulator base for cracks. If
cracks are found, replace the igniter.
FIG. 18
1/8 - 3/16 in.
(3.18 - 4.78mm)
IGNITER MOUNTING
BRACKET
IGNITER
CABLE
Transformer
The transformer receives 120 volts and reduces it to 24 volts.
The 24 volts is supplied to the ignition controller to start the
ignition process. See Fig. 19.
-- If 24 volts is not supplied from the transformer to the ignition
controller, the heater will not operate.
FIG. 19
Signal Conditioner
The conditioner receives the incoming electrical signal from
the building’s environment control and then amplifies it to allow
operation of the heater’s variable rate gas control valve.
This component operates off of 24 VAC received from the
transformer in the heaters control box.
If the transformer does not supply 24 VAC to the conditioner, or
if the conditioner is defective, the variable rate gas control will
operate at minimum heat output only. (See data plate or page
4 of this manual for minimum output, depending on model.)
FIG. 20
TRANSFORMER
120 VAC INPUT
TERMINAL
24 VAC OUTPUT
TERMINAL
Building controller
control signal
connections
(screw terminal)
mA or DCV
Output to the gas
control valve
24V transformer
connection
Selector
Switch