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53
TROUBLESHOOTING GCCO-PP / -PT CONT’D
NO HEAT, MANUAL MODE
PROBABLE CAUSE
CORRECTIVE ACTION
Defective back-up toggle
switch
Confirm that toggle switch is in the “ON” position.
Check toggle switch for normal operation.
Defective back-up relay
Check for 120VAC at relay coil.
If no voltage is present:
Confirm that points are making.
If voltage is present:
Replace relay.
Defective component
transformer
Confirm that 120VAC is feeding primary coil.
Confirm that 24VAC is at secondary coil.
Failed Ignition
See Failed Ignition portion of this manual.
Check for 24VAC at MV on the spark modual to ground.
If no voltage is present:
Confirm that pilot is lit.
Replace as necessary.
If voltage is present:
Check thermostat for normal operation.
Defective Thermostat
Confirm that thermostat has 24VAC.
If no voltage is present
Check component transformer and wiring for normal operation.
If voltage is present
Check thermostat for normal operation. Replace as necessary.
Defective centrifugal switch in
motor
Disconnect centrifugal switch and check of continuity while the
motor is running.
If no continuity is present:
Replace motor.
If continutiy is present:
Check thermostat for normal operation.
Check wires
Defective main valve
Check for 24VAC across valve.
If no voltage is present:
Confirm that wires have continuity.
If voltage is present:
Replace valve.
Summary of Contents for GCCO-C
Page 29: ...29 GENERAL CONT D ONE PAN TWO PAN THREE PAN FOUR PAN FIVE PAN ...
Page 59: ...59 TECHNICAL DATA CONT D GCCO C TEST POINT LAYOUT TP 2 TP 1 TP 3 TP 4 TP5 TP6 TP7 ...
Page 61: ...61 WIREING DIAGRAM GCCO T ...
Page 62: ...62 WIRING DIAGRAM GCCO AP ...
Page 63: ...63 WIRING DIAGRAM GCCO SII ...
Page 64: ...64 WIRING DIAGRAM GCCO C ...
Page 65: ...65 WIRING DIAGRAM GCCO PP ...
Page 66: ...66 WIRING DIAGRAM GCCO PT ...