Bradford White RG130T N Series Service Manual page 30

TEMPERATURE SENSOR TESTING (Honeywell)
Step 1. If control has gone into lockout due to
excessive tank temperature (four
flashes, three second pause), reset
control by rotating gas control knob to
"OFF" position and wait a minimum of
five (5) minutes. Then follow lighting
instructions and return the gas control
knob to a desired setpoint.
Step 2. Observe green light indicator. Does
status code 4 (four flashes, three
second pause) appear?
a) If no, resume normal operation.
b) If yes, continue with Step 3.
Step 3. Following "Honeywell Cover Removal,"
"Honeywell Valve Body Removal and
Temperature Sensor Removal"
instructions, disassemble gas control to
access the temperature sensor.
Step 4. With the temperature sensor still in the back plate, use a multimeter set to the ohms
setting, determine the resistance of the temperature sensor (see photo).
Step 5. See next page to obtain water temperature. Are temperature sensor resistance values
correct?
a) If no, replace the temperature sensor.
b) If yes, replace the gas control.
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SERVICE PROCEDURE RG-VI
Gas Control Testing, Disassembly, & R eplacement
(Honeywell ONLY)
CAUTION
DO NOT use standard multimeter probes
for this test. Doing so will damage
connector. Use special pin type electronic
probes or small diameter wire pins
inserted into connector.
NOTE: Using a multi-meter set to the ohms setting,
insert one-meter probe into center wire position of
thermal well connector, insert the second probe into
either of the outside wire positions (see photo).
Alternate the probe on the outside position to the
opposite outside wire position (see photo).
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