17
201835
OWNER’S MANUAL
www.desatech.com
OBSERVED PROBLEM
Ignition failures
POSSIBLE CAUSE
1. Glo bar will not glow - with blower run-
ning and microswitch engaged
2. Glo bar glows but burner will not
come on
3. Glo bar operating and gas valve open-
ing but burner will not light
4. If the ignitor remains on after main
burner ignition or the valve chatters, re-
verse the 120-volt A.C. connections at
the wall receptacle
REMEDY
1. Check the following:
A. Check for 24 volts A.C. across yellow and
orange wires at ignition control. If no volt-
age, check microswitch and limit switch for
circuit completion as well as wiring and wir-
ing connections
B. Voltage present across yellow and orange wires,
check for 120-volt input to ignition control
across red and blue wires. If no voltage, check
wiring all the way back to power supply
C. 120 volts present across red and blue wires,
check for 120 volts across the two white wires
at ignition control. If no voltage, replace igni-
tion control
D. Voltage present across the two white wires,
check wiring and wire connections to glo bar
E. If wiring and wire connections okay, replace
glo bar. (Glo bar broken)
2. A. Check for voltage (24 volts A.C.) at valve
40 seconds after glo bar begins to glow. If
voltage present but valve not opening, replace
valve
B. If no voltage at valve, check brown wire at
ignition control for continuity and good con-
nection
C. If wire and wire connections okay, replace
ignition control
3. A. Check gas flow through burner. If no gas is
coming through burner, check for obstruc-
tion in gas line, main burner orifice, or main
burner
B. If thermostat okay, check for 24 volt A.C.
circuit completion across yellow and orange
wires at ignition control. If no voltage, check
for circuit completion through limit switch
and microswitch
C. If voltage is present at ignition control across
yellow and orange wires yet burner contin-
ues to go off, replace ignition control
4. A. If polarity is okay yet burner continues to go
off, check thermostat to be sure it is still com-
pleting the valve circuit. If not, check for
excessive amp draw in valve circuit
B. If thermostat okay, check for 24 volt A.C.
circuit completion across yellow and orange
wires at ignition control. If no voltage, check
for circuit completion through limit switch
and microswitch
C. Voltage present at ignition control across
yellow and orange wires yet burner contin-
ues to go off, replace ignition control
Continued
TROUBLESHOOTING
Continued
