Service manual

troubleshooting trees

T r o u b l e s h o o T i n g T r e e s • C o m b i t h e r m C t e x p r e s s t e C h n i C a l s e r v i C e m a n u a l • D – 4

No Convection Heat (380-415V, 3PH)

Is N-6 oven temperature

probe below set point?

Is K-41 contactor coil

energized?

Is K-41 contactor closing?

N-6 must be below set

point

Yes

L1/A1 from RBH X4/412,

L2/A2 from N7 high limit

Yes

Replace K-41 contactor

L1/L2/L3 supplied from K-77

contactor 1/3/5

Is L1/L2/L3 voltage across

terminals 1/3/5 on K-41

contactor?

Is voltage across terminals

2/4/6 on K-41 contactor?

Replace K-41 contactor

Is voltage across 3-4

and 2-5 and 1-6 on E-41

convection elements?

Repair wiring between

F10/11/12 fuses and E-41

Is there L1/L2/L3 voltage

across terminal 1 at

F10/11/12 fuses?

Repair blown F10/11/12

fuse(s)

Is E-41 drawing current on

all legs?

Yes

Ohm out E-41 element

and replace if necessary

Convection cycle is

operating

Yes

Repair wiring between K-42

and F10/11/12

Is there L1/L2/L3 voltage

across terminal 2 at

F10/11/12 fuses?