Convection Roast Cycle - Thermador SMW272 B Service Manual

Lower Oven Section
NOTE: The Convection Roast cycle is a continuation of the Convection Roast Preheat cycle.
Press the CONVECTION ROAST keypad and the following events will occur on the relay board:
• The L1 Relay connects L1 line voltage to the Convection and Bake Elements.
• Bake Relay K1 and Convection Relay K3 alternately open and close and connect the L2 (120-volt)
line to the Bake and Convection elements. NOTE: The Convection Element is on for 29-seconds,
and draws 11-amperes during each 1-minute cycle. The Bake Element is on for 30-seconds, and
draws 11-amperes during each 1-minute cycle.
• Convection Motor Relay K4 closes and activates the Convection Motor.
• After the Convection Roast Preheat temperature has been reached, Relays K2 and K3 cycle off
(open). When the thermostat cycles back on, the circuit switches from Relays K2 and K3, to Relays
K1 and K3, for the rest of the selected temperature and cooking time. Relays K1 and K3 will cycle
on and off to maintain the selected temperature.
L1
L2
K6
Cooling Fan
N.O.
Relay
Stalled
Cooling
Fan Relay
Fan

Convection Roast Cycle

High-Temp
Cutout
Air
N.O.
Switch
Stalled Fan
Relay Contacts
N.O.
N.O.
L1 Relay
N.C.
K1
K2
Bake
N.O.
Broil
Relay
Relay
Bake
30 Seconds
11 Amps
K8
N.O. = Normally Open Contacts
N.C. = Normally Closed Contacts
= Neutral Return
Page 79
SMW Oven Service Manual
K4
K3
Conv.
N.O. N.O.
Conv.
Motor
Relay
Relay
Conv.
Broil
29 Seconds
11 Amps
N.O.
Conv.
Motor