Maintenance
34
Troubleshooting Top Oven Section
HOW TO USE THIS TROUBLESHOOTING GUIDE
Always troubleshoot the circuit in the following sequence. Troubleshoot each oven section this way. Go
from: 1) COOL DOWN 2) HOT AIR 3) STEAM 4) COMBI
If the oven shorts or trips the redundant contactor when selecting the mode switch to the COOL DOWN
position, shut off the main breaker, turn the mode selector switch to COOL DOWN and then turn the main
breaker back on.
COOL DOWN MODE
POSSIBLE CAUSE(S)
SUGGESTED REMEDY
SYMPTOM: Motor doesn't run in cool down.
NOTE: The COSĆ5H has a redundant contactor (K1 & K6) which are in series with the 440V operating
components (hot air & steam elements, motors). If a redundant contactor is tripped, the conĆ
trol circuit lights will work (green OVEN ON (H6) and hot air (H5) but the motors and elements
will not work until the fault is determined and the redundant contactor is reset.
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Main circuit breaker is OFF
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StepĆdown transformer (T1) is defective
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Mode selector switch (S1) is not closing beĆ
tween terminals 23 & 24
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Motor contactor K8 is not closing
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The motor overload (OL6) has tripped.
S
The circuit overload (K6) has tripped.
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Verify the main breaker is not tagged out or the
breaker has tripped. If the main breaker is tripped,
there is a high probability of a steam or hot air eleĆ
ment short. Proceed to the appropriate trouble
shooting section and review. Overload has tripped.
Isolate which oven section is tripping the breaker.
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Verify 440V input to the transformer. Check the
transformer coils. Approximately 2.2 ohms priĆ
mary / .7 ohms secondary. Output is 220VAC.
Replace if needed.
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Verify switch is closing with meter. Replace if
needed.
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The contactor coil resistance is approximately
1.39K ohms. Verify voltage between the coil A1
and A2.
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Check windings of motor. Resistance of windĆ
ings is approximately 85 ohms. Running current
is .5 plus amps. To reset the overload, lift the
plastic cover and push in test reset. Verify the
overload setting, .63. Review Convection Motor
runs Intermittently" before replacing.
S
See following circuit description
