Proof Pre-Heat; Proof Preheat; Proof Mode - Thermador C302 Service Manual

Sequence Of Events:
1) K4, K8, K9 relays close.
2) K4 relay energizes both cooling motors; airflow from cooling motor closes
the "air switch" contacts the completed "air switch" circuit signals the
board (signal voltage). Note: if the air switch circuit is not completed
within 40 seconds, the board will interpret an cooling fan fault and
display an F34 error code for the upper oven, and an F64 error code for the
lower oven.
3) Pin header P14 on the relay board sends 24 VDC To the double line break
relay {DLB) coil when the coil is energized; the DLB contacts close.
Current flows from L1 to one leg of the bake, broil and convection
elements.
4) Bake relay K8 and broil relay K9 alternately open and close and send
current from l2 to the other leg of the bake and broil elements. The bake
element is on for 10 seconds, and the broil element is on for 10 seconds
during each 1-minute cycle.

Proof Pre-Heat

Proof Mode

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