Service Manual

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SERVICE PROCEDURE RG-II
Thermocouple/Thermopile Testing and
Replacement
OPEN CIRCUIT THERMOPILE TESTING
(Resideo & White Rodgers Electronic)
The following test should be performed while the pilot flame is on.
Step 1.
Step 2.
Step 3.
Step 5.
If thermopile reading is between 350mV - 850mV, reconnect red wire to positive (+) terminal of
the
gas control.
Release the gas control knob and turn to desired setting to resume normal operation.
Step 6.
Step 4. If reading is less than 350mV, resettable thermal switch must be tested. Refer to Service Process
RG-III. If resettable thermal switch is closed, replacement of pilot assembly is recommended
following Service Procedure RG-III.
Turn knob to pilot position and depress.
Contin
ue pressing knob and remove the red (+) wire from resettable thermal door switch.
Using
a multimeter capable of measuring millivolts, connect the positive side of the multimeter
to
t
he terminal of the resettable thermal switch. Connect the negative side of the multimeter to
any
earth
ground location (jacket base, screw, etc.). Normal thermopile operation will be
between
350mV - 850mV.
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