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55175G 17
TROUBLEShOOTING
MILLIVOLT SYSTEM
Note: Before troubleshooting the system, make sure the gas shutoff valve is ON.
The two most common causes of a malfunctioning gas appliance are:
1. Loose wiring connections
2. Construction debris clogging the pilot and/or gas control valve lter
OBSERVED PROBLEM
Pilot will not light
Pilot will not stay lit
No gas to burner, although wall
switch and valve are set to the
ON position
Frequent pilot outage
Pilot goes out when wall switch
is ON
POSSIBLE CAUSE
1. No gas supply or shutoff
valve is OFF
2. Air in gas line
3. Construction debris clog-
ging pilot orice
4. Low gas pressure
5. Control valve knob is not on
the PILOT position
6. Kinked pilot line
7. Bad valve
1. Loose wiring on thermopile
to control valve.
2. No millivolt current is being
sent back to regulator
3. If valve knob and wall switch
are in the ON position, prob-
able defective control valve
1. Wall switch wires defective
2. Thermopile or sensor not
generating sufcient voltage
1. Pilot flame may be too
low, causing safety pilot to
“drop out”
1. Millivolt output on thermo-
pile too high
REMEDY
1. Check to see if you have gas
supply
2. Hold regulator control valve
in the PILOT position for 2 to
3 minutes to purge air. If you
smell gas stop and wait for a
few minutes before trying to
light the replace
3. Remove debris and dirt, in-
spect and clean any other
possible obstructions
4. Contact your gas supplier
5. Refer to section on pilot
lighting
6. Have a qualied technician
replace pilot line
7. Replace control valve (see
Replacement Parts and Acces-
sories, page 19)
1. Check wiring connections.
Refer to wiring diagrams on
page 15
2. Have a qualified technician
check millivolts
3. Have a qualified technician
replace valve (see Replace-
ment Parts and Accessories,
page 19)
1. Check electrical connections
and wires for continuity
2. See Pilot will not stay lit,
above
1. Clean and adjust pilot ame
for maximum ame impinge-
ment on thermopile
1. Have a qualified technician
replace thermopile