Midco G69B - Manual (Page 12)

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VI. PILOT LIGHTS, NO LOCKOUT ON FLAME
SAFEGUARD, NO MAIN GAS.
A. Low gas pressure.
B. Misadjusted main regulator.
C. Blocked regulator vent.
D. Defective main regulator.
E. No power at main valve(s).
F. Blocked main valve bleed line (If equipped).
G. Defective main valve(s).
H. Closed test cock.
I. Input adjuster closed.
J. Defective flame safeguard.
VII. MAIN FLAME LIGHTS, BUT GOES OUT, PILOT
RELIGHTS.
A. Poor pilot.
B. Pilot gas pressure drops severely when main gas
valve opens.
VIII. SHORT MAIN FLAME.
A. Too little gas.
B. Low gas pressure.
C. Defective main regulator.
D. Misadjusted main regulator.
E. Too much air.
F. Partially closed test cock.
IX. LONG, HAZY FLAME.
A. Too much gas.
B. High gas pressure.
C. Defective main regulator.
D. Misadjusted main regulator.
E. Misadjusted input adjuster.
F. Too little air.
G. Dirty blower wheel.
X. MAIN VALVE(S) FAILS TO SHUT OFF OR LEAKS.
A. Defective valve(s).
B. Defective valve actuator.
C. Dirty valve seat.
XI. MOTOR OVERLOAD FREQUENTLY TRIPS OUT.
A. Low voltage.
B. Spasmodic start.
C. Defective motor.
D. High ambient temperature.
XII. FLAME SAFEGUARD NEEDS FREQUENT
RESETTING.
A. See IV above.
B. See V above.
C. See VI above.
XV TROUBLE CHART
Make sure the thermostat and operating controls are calling for heat. Defective wiring or loose connecting can simulate the
component defects outlined below. Check associated wiring before replacing a component. ELECTRICAL AND FLAME
CHECKS MUST BE MADE IN THE ORDER LISTED
NOTE: Some of the probable causes listed above apply only to certain models as indicated, therefore some may not
apply to your particular case.
I. MOTOR FAILS.
A. No power to flame safeguard.
B. Flame safeguard locked out.
C. Defective flame safeguard.
D. Defective motor relay.
E. Motor overload "out".
II. MOTOR FAILS TO START, FLAME SAFEGUARD
ENERGIZED.
A.
Motor overload "out."
B. Defective motor.
C. Defective flame safeguard.
III. MOTOR RUNS CONTINUOUSLY, NO LIGHTING
ATTEMPT.
A. Defective air switch.
B. No air pressure at air switch.
C. Defective purge timer.
D. Defective flame safeguard.
IV. PILOT DOES NOT LIGHT, FLAME SAFEGUARD
LOCKS OUT.
A. No pilot gas.
B. Low pilot gas pressure.
C. Defective pilot gas regulator.
D. Misadjusted pilot regulator.
E. Blocked pilot regulator vent.
F. Defective pilot solenoid valve.
G. Defective spark electrode.
H. Misadjusted spark electrode.
I. Defective spark cable.
J. Defective spark generator.
K. Clogged or incorrect pilot orifice.
L. Defective pilot tip.
M. Excess pilot air.
N. Air orifice missing.
O. Clogged pilot air tube.
P. Defective flame safeguard.
V. PILOT LIGHTS, FLAME SAFEGUARD LOCKS OUT.
A. Poor flame signal.
B. Poor pilot flame.
C. Misadjusted pilot regulator.
D. Low gas pressure.
E. No pilot air (see above).
F. Excess pilot air (see above).
G. Defective pilot tip.
H. Defective flamerod wire.
I. Defective or misadjusted flamerod.
J. Defective amplifier.
K. Defective flame safeguard.