Thermador C271 Service Manual - Proof Pre-Heat

Proof Pre-Heat

Proof Mode

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.

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