Thermador SMW 272 B, Service Manual, Page: 82 / 84

Page 80
Lower O ven Section SMW O ven Service Manual
Press the SELF-CLEAN keypad and select a self-clean time period and the following events will occur on
the relay board:
• Line Relay
K8
closes.
• Cooling Fan Relay
K6
closes and turns the Cooling Fan on.
• Cooling Fan air flow closes the Air Switch and activates the Stalled Fan Relay.
• The Stalled Fan Relay contacts close and supply L1 to one side of Relay
K8 (already activated)
.
• The
L1
Relay connects L1 line voltage to the Broil Element.
• Broil Relay
K2
closes and connects the L2 (120-volt) line to the Broil element. N O TE: The Broil
Element is on for 60-seconds, and draws 15-amperes during each 1-minute cycle. It is also on
continuously for the first 55-minutes of the Self-Clean cycle, or unil the oven reaches 850˚F.
Self-Clean Cycle — Preheat Below 840
˚
L2
L1
Cooling
Fan
K6
Cooling Fan
Relay
N.O.
Stalled
Fan Relay
Air
Switch
N.O.
Bake
K1
Bake
Relay
N.O.
K2
Broil
Relay
N.O.
Broil
60 Seconds
15 Amps
N.O. = Normally Open Contacts
N.C. = Normally Closed Contacts
= Neutral Return
K8
L1 Relay
N.C.
N.O.
High-Temp
Cutout
Stalled Fan
Relay Contacts
N.O.
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