Motor And Blower Wheel Check - Space-Ray LTU 160/100-N7 Installation And Operation Instructions Manual

TO CHECK SPARK IGNITION CIRCUIT.
▲WARNING: The ignition circuit generates a 20,000 Volt open circuit and electrical shock can result.
a. Check ignition cable.
b. Check external fuse located inside the draft inducer junction box.
c. Verify power (24V) at module input terminals and output terminal to gas valve.
d. Replace spark module if fuse and power are OK.
IGNITION MODULE DIAGNOSTICS
The LED located on the ignition module will flash ON for ¼ second, then OFF for ¼ second during a fault
condition. The pause between fault codes is 3 seconds.
LED Indication
Steady On
2 Flashes
3 Flashes
TO CHECK FLAME SENSOR CIRCUIT
The flame current is the current that passes through the flame from the sensor to the ground. The
minimum flame current necessary to keep the system from lockout is 0.7 micro-amps.
a. To measure the flame current, connect an analog DC micro-ammeter to the FC- and FC+ terminals per
diagram. The meter should read 0.7 micro-amps or higher when the burner is running full on.
b. If the meter reads below zero, the meter leads are reversed. Disconnect power and reconnect the meter
leads for proper polarity.
c. Remove micro-ammeter. Return system to normal operation.
23.5)

MOTOR AND BLOWER WHEEL CHECK

If draft inducer motor fails to run:
a. Check power supply to junction box.
b. Check for loose or broken motor lead wire.
c. Check to see that blower wheel turns freely and is not rubbing housing. Blower wheel may have worked
loose from shaft and jammed against housing.
d. Check for blower wheel damage; replace if necessary. If no damage, readjust blower wheel on shaft &
retighten set screw.
e. If all above does not correct, replace motor.
(Fenwal #35-6087J1-034 module only)
Error Mode
Internal Control Fault
Flame Sense Fault
Ignition Lockout
(Fenwal #35-6087J1-034 module only)
-62-
Form #43155010
Dec 2017