TROUBLESHOOTING

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.

TROUBLESHOOTING GUIDE - Millivolt GAS CONTROL SYSTEM

 

SYMPTOM

POSSIBLE CAUSES

CORRECTIVE ACTION

1.

Spark igniter will not light pilot after

A. Defective igniter

Check for spark at electrode and pilot; if no spark and

 

repeated triggering of igniter button.

(no spark at electrode).

electrode wire is properly connected, replace igniter.

 

WARNING: if the pilot will not light

B. Defective or misaligned electrode at pilot

Using a match, light pilot. If pilot lights, turn off pilot

 

(spark at electrode).

and trigger the igniter button again. If pilot lights, an

 

after 1 minute of attempting, wait

 

 

improper gas mixture caused the bad lighting and a

 

for at least 5 minutes for gas to

 

 

 

longer purge period is recommended. If pilot will not

 

clear before attempting again.

 

 

 

light – check gap at electrode and pilot – should be 1/8"

 

 

 

 

 

 

to have a strong spark. If gap measures 1/8", replace

 

 

 

pilot (see Figures 13 or 14 on Page 11).

 

 

C. Gas supply pressure errant.

Check inlet gas pressure. It should be within the limits

 

 

 

as marked on the rating plate.

 

 

D. Pilot orifice plugged.

Clean or replace pilot orifice.

 

 

 

 

2.

Pilot will not stay lit after

A. Defective pilot generator

Check pilot flame, it must impinge on thermocouple

 

carefully following the lighting

(thermocouple).

(see Figures 13 or 14 on Page 11). Clean and/or

 

instructions.

 

adjust pilot for maximum flame impingement on

 

 

 

thermocouple. Ensure that the connection between

 

 

 

the valve and thermocouple are tight and secure.

3.

Pilot burning, no gas to burner, Valve

A. Wall switch or wires defective.

Check wall switch and wires for proper connections.

 

knob “ON,” and the (standard) burner

 

Jumper wire across terminals at wall switch, if burner

 

OFF/ON switch is “ON." Read impor-

 

comes on, replace defective wall switch. If okay, jumper

 

tant note below.

 

wires across wall switch wires at valve, if burner comes

 

 

 

on, wires are faulty or connections are bad.

 

IMPORTANT NOTE: If an optional

B. Thermopile may not be generating suf-

Check thermopile with millivolt meter. Take reading

 

ficient millivolts.

at thermopile terminals of gas valve. Should read

 

*remote switch is used for burner

 

 

325 millivolts minimum with optional wall switch

 

operation, if the standard burner

 

 

 

“OFF.” Replace faulty thermopile if reading is below

 

OFF/ON switch is still installed on

 

 

 

specified minimum.

 

appliance it must be in the "OFF"

 

 

position.

C. Plugged burner orifice.

Check burner orifice for blockage and remove.

 

 

 

*Optional remote switch kits - wall

 

 

 

D. OFF/ON Switch & *Remote Switch are in

When turning on the burner using a *remote switch,

 

switch, wall thermostat or remote

the "ON" position resulting in excessive

ensure that the standard OFF/ON switch is in the "OFF"

 

control.

resistance.

position. If both switches are in the ON position, it

 

 

 

may result in excessive resistance (& millivolt drain-

 

 

 

age) and the burner may not come on.

4.

Frequent pilot/burner outage prob-

A. Pilot flame may be too low or blowing (high)

Clean and/or adjust pilot flame for maximum flame

 

lem.

causing the pilot/valve safety to drop out.

impingement on thermocouple (see Figures 13 or

 

 

 

14 on Page 12).

 

TROUBLESHOOTING GUIDE - ELECTRONIC IGNITION SYSTEM

 

 

 

 

 

 

SYMPTOM

POSSIBLE CAUSES

CORRECTIVE ACTION

 

 

 

 

 

 

1.

Burner will not light.

A. Faulty Valve System.

See Below.

 

 

 

 

 

 

 

 

B. “OFF/ON” or wall switch defective.

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.

 

2.

Burners come “ON,” then turns “OFF.”

A. Burner orifice plugged.

Check main burner orifice(s) for blockage. Clean

 

 

 

 

or replace.

 

 

 

B. Obstructed vent system.

Check vent system for obstructions.

 

 

 

 

 

 

 

 

NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.

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Milwaukee LMDVT-3328CNM manual Troubleshooting, Symptom Possible Causes Corrective Action