Heatilator • ADI-ZCFB-S • 2032-910 Rev. i • 6/09
30
A. Standing Pilot Ignition System
13
Troubleshooting
With proper installation, operation, and maintenance your gas appliance will provide years of trouble-free service. If you do
experience a problem, this troubleshooting guide will assist a qualifi ed service person in the diagnosis of a problem and the
corrective action to be taken. This troubleshooting guide can only be used by a qualifi ed service technician.
Symptom
Possible Causes
Corrective Action
1. After repeated triggering
of the red or black piezo
ignitor button, the spark
ignitor will not light the pilot.
a. Defective ignitor.
Check the spark at the electrode and pilot. If no spark and electrode
wire is properly connected, replace the ignitor.
b. Defective pilot or misaligned
electrode (spark at electrode).
Using match, light the pilot. If the pilot lights, turn off the pilot and
trigger the red piezo ignitor button again. If the pilot lights, an im-
proper gas/air mixture caused the bad lighting and a longer purge
period is recommended. If the pilot will not light, ensure the gap
at the electrode and pilot is one-eighth (1/8) inch to have a strong
spark. If the gap is OK, replace the pilot.
c. No gas or low gas pressure.
Check the remote shut-off valves from the fi replace. Usually, there
is a valve near the gas main. There can be more than one (1) valve
between the fi replace and the main.
d. No LP in tank.
Check the LP (propane) tank. You may be out of fuel.
2. The pilot will not stay lit
after carefully following the
lighting instructions.
a. Defective thermocouple.
Check that the pilot fl ame impinges on the thermocouple. Clean
and/or adjust the pilot for maximum fl ame impingement.
Ensure that the thermocouple connection at the gas valve is fully
inserted and tight (hand tighten plus 1/4 turn).
Disconnect the thermocouple from the valve, place one millivolt
meter lead wire on the tip of the thermcouple and the other meter
lead wire on the thermocouple copper lead. Start the pilot and hold
the valve knob in. If the millivolt reading is less than 15mV, replace
the thermocouple.
b. Defective valve.
If the thermocouple is producing more than 15 millivolts, replace
faulty valve.
3. The pilot is burning,
there is no burner fl ame,
the valve knob is in the ON
position, and the ON/OFF
switch is in the ON position.
a. ON/OFF switch or wires
defective.
Check the ON/OFF switch and wires for proper connections. Place
the jumper wires across the terminals at the switch. If the burner
comes on, replace the defective switch. If the switch is OK, place the
jumper wires across the switch wires at the gas valve. If the burner
comes on, the wires are faulty or connections are bad.
b. Thermopile may not be gener-
ating suffi cient millivoltage.
If the pilot fl ame is not close enough physically to the thermopile,
adjust the pilot fl ame.
Be sure the wire connections from the thermopile at the gas valve
terminals are tight and that the thermopile is fully inserted into the
pilot bracket.
Check the thermopile with a millivolt meter. Take the reading at
TH-TP&TP terminals of the gas valve. The meter should read 325
millivolts minimum, while holding the valve knob depressed in the
pilot position, with the pilot lit, and the ON/OFF switch in the OFF
position. Replace the faulty thermopile if the reading is below the
specifi ed minimum.
With the pilot in the ON position, disconnect the thermopile leads
from the valve. Take a reading at the thermopile leads. The read-
ing should be 325 millivolts minimum. Replace the thermopile if the
reading is below the minimum.
