Download GAS VALVE SOLENOID CHECK

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GAS VALVE SOLENOID CHECK
STEP 1.
Make sure the manual control located on the gas valve is in the “ON” Position.
STEP 2.
With the thermostat
calling for heat, the
induced draft motor
operating and the
pressure switch
closed, check for 24
volts at the gas valve
solenoid terminals
(fig. 1,2) If the gas
valve is a two stage
model, check voltage
to the second stage
solenoid by initiating
a second stage call
for heat by jumpering fig. 1
the second stage heat
thermostat terminal at the
IFC. If there is no voltage,
be sure the induced draft
motor has closed the vent
pressure switch contacts.
(second stage pressure
switch for second stage
solenoid.)
fig. 2
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STEP 3.
If 24 volts is not present at
the gas valve solenoid
terminals, check for
voltage at the IFC
(INTEGRATED
FURNACE CONTROL)
board terminals that feed
24 volts to the gas valve
solenoid (fig 3.) If there is
voltage at the control board
but not at the gas valve,
check for a lose or broken
wire, or an open safety
fig. 3
circuit. If there is no
voltage at the appropriate control board terminals, Replace the control board.
STEP 4. If 24 volts is present at the gas valve solenoid, but the gas valve does not
open, The gas valve is defective and must be replaced.