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TROUBLESHOOTING THE MILLIVOLT CONTROL SYSTEM
Note: Before troubleshooting the gas control system, Ensure external gas shut off valve, located at gas supply inlet, (and wall switch, iff applicable), is
in the "ON" position. Important: Valve system troubleshooting should only be accomplished by a qualified service technician.
SYMPTOM
1. Spark Igniter will not light pilot
after repeated triggering of
Igniter button.
2. Pilot will not stay lit after
carefully following the lighting
instructions.
3. Pilot burning, no gas to burner,
Valve knob "ON," Wall Switch
"ON."
4. Frequent pilot/burner outage
problem.
TROUBLESHOOTING GUIDE - ELECTRONIC IGNITION SYSTEM
SYMPTOM
1. Burner will not light.
2. Burners come "ON," then turns
"OFF."
POSSIbLE CAUSES
A. Defective igniter
(no spark at electrode).
b. Defective or misaligned electrode at pilot
(spark at electrode).
C. Gas supply pressure errant.
D. Pilot orifice plugged.
A. Defective pilot generator
(thermocouple).
A. Limit Switch defective.
b. Wall switch or wires defective.
C. Thermopile may not be generating suf-
ficient millivolts.
D. Plugged burner orifice.
E. OFF/ON Switch & *Remote Switch are in
the "ON" position resulting in excessive
resistance.
A. Pilot flame may be too low or blowing (high)
causing the pilot/valve safety to drop out.
POSSIbLE CAUSES
A. Faulty Valve System.
b. "OFF/ON" or wall switch defective.
A. Burner orifice plugged.
b. Obstructed vent system.
CORRECTIVE ACTION
Check for spark at electrode and pilot; if no spark and elec-
trode wire is properly connected, replace Igniter.
Using a match, light pilot. If pilot lights, turn off pilot and
trigger the igniter button again. If pilot lights, an improper
gas mixture caused the bad lighting and a longer purge
period is recommended. If pilot will not light – check gap
at electrode (igniter rod) and pilot – should be 1/8" to have
a strong spark. If gap measures 1/8", replace pilot (see
Figure 17 on Page 18).
Check inlet gas pressure. It should be within the limits as
marked on the rating plate.
Clean or replace pilot orifice.
Check pilot flame, it must impinge on thermocouple (see
Figure 17 on Page 18). Clean and/or adjust pilot for maxi-
mum flame impingement on thermocouple. Ensure that the
connection between the valve and thermocouple are tight
and secure.
Isolate the "limit" switch. Disconnect the wires from the
"ON/OFF" switch and the valve (label wires for reattachment).
Test for continuity with a multimeter. If continuity is not
indicated, switch is defective and must be replaced.
Check wall switch and wires for proper connections. Jumper
wire across terminals at wall switch, if burner comes on,
replace defective wall switch. If okay, jumper wires across
wall switch wires at valve, if burner comes on, wires are
faulty or connections are bad.
Check thermopile with millivolt meter. Take reading at ther-
mopile terminals of gas valve. Should read 325 millivolts
minimum with optional wall switch "OFF." Replace faulty
thermopile if reading is below specified minimum.
Check burner orifice for stoppage and remove.
When turning on the burner using a *remote switch, ensure
that the unit mounted (optional) OFF/ON switch is in the
"OFF" position. If both switches are in the ON position, it
may result in excessive resistance (& millivolt drainage)
and the burner may not come on.
Clean and/or adjust pilot flame for maximum flame impinge-
ment on thermocouple (see Figure 17 on Page 18).
CORRECTIVE ACTION
See Below.
Disconnect the two black wires from the wire nuts. Test
switch(s) for continuity with a multimeter. If continuity is not
indicated, switch(s) is defective and must be replaced.
Note: Before replacing "OFF/ON" switch, Ensure to check
wiring for loose connections or broken wires and repair
as needed.
Check main burner orifice(s) for blockage. Clean or re-
place.
Check vent system for obstructions.
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