Convection Cycle - Convection Preheat And Convection Mode - Thermador SMW272 B Service Manual

Lower Oven Section
Convection Cycle – Convection Preheat & Convection Mode
Press the CONVECTION keypad and select an oven temperature 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 Convection Element.
• Convection Relay K3 closes and connects the L2 (120-volt) line to the Convection element. NOTE:
The Convection Element is on for 60-seconds, and draws 11-amperes during each 1-minute cycle.
• Convection Motor Relay K4 closes and activates the Convection Motor.
L1
L2
K6
Cooling Fan
N.O.
Switch
Relay
Stalled
Cooling
Fan Relay
Fan
High-Temp
Cutout
Air
N.O.
Stalled Fan
Relay Contacts
N.O.
K8
N.O.
L1 Relay
N.C.
K1
K2
Bake
N.O.
Broil
Relay
Relay
Bake
N.O. = Normally Open Contacts
N.C. = Normally Closed Contacts
= Neutral Return
Page 77
SMW Oven Service Manual
K4
K3
Conv.
N.O. N.O.
Conv.
Motor
Relay
Relay
Conv.
Broil
60 Seconds
11 Amps
N.O.
Conv.
Motor