Thermador Oven SC301ZS/01 not heating

[Gambit]

Model Number

SC301ZS/01

Brand

Thermador

Age

More than 10 years

Hello! I have a Thermador Electric Oven SC301ZS/01 and it is not heating. When energized it reads BAKE is ON and sits at 100*. Cooling fan turns on, just never any heat.

What I have tried:

• Replaced main bake element. Original one actually worked (discovered after i pulled the entire oven out), but the connector had broken/melted. Replaced with similar high temp connector.
• Tested new element for continuity (passed)
• Tested element for voltage. Either side to ground (metal frame) is 120v
• Tested L2 to L1 on board, 240v
• Cooling Fan works, relay clicks when sail is actuated
• Measured DBL to N on relay board and got 120v

But when I check for voltage across both sides of the bake element I am not getting 240v

There is a semi-regular clicking noise. Perhaps from the SFR? would this be faulty? I saw elsewhere on the forum to measure voltage to the wires leading to the SFR (COM and N) and (NO and N). On one I got 120v and the other 0v (which thread said was what i want).

Need to double check if Broil and Convection element have continuity...but if I have the oven in BAKE only (not convection) I thought it used 100% of the bake element, no other elements.

Any thoughts? I appreciate it!

Thanks

 

[Dan O.]

Tested element for voltage. Either side to ground (metal frame) is 120v

That is meaningless. You could be reading the same 120 volts on each side if you left the element connected in the circuit.

But when I check for voltage across both sides of the bake element I am not getting 240v

See!

Tested L2 to L1 on board, 240v

Is that the power IN or power OUT?

What is needed is to check the power OUT, where the element gets connected to the control.


Dan O.

 

[Gambit]

I was trying to follow steps in this thread:

FIXED - Thermador SMW272YP - not heating, 100F on display

Thanks bud! I'll check those things in the next couple of days. A sail switch replacement looks pretty expensive so hopefully I can confirm that this SFR is also bad and send it back to ebay. Then I can try to find another one if there are any good ones left anywhere :P

www.applianceblog.com

• HTCO has continuity (didnt need to be reset)
• Per post #9 the following check out
  • Fan works
  • 120 VAC between DLB and N on relay board (per the image)
    
  • Voltage is 240 VAC between L1 and L2 out (per the image)
    

Then moving on to post #13:

• L2 and N is 120 VAC
  
• L1 and L2 in is 240 VAC
  

Next post states if both of those are good it is most likely the SFR.

Post #16 states:

One last voltage measurement just to confirm the SFR is the problem. On the SFR measure the voltage between the NO terminal and cabinet ground ( any cabinet screw or metal surface) and then between COM terminal and cabinet ground. One will show 120 VAC and one will show 0 VAC. If both show 0 VAC the sail switch is the problem.

The sail switch is working.

I do, however, get a very audible set of clicks from the relays by BAKE, L2, etc on the control board. Sometimes 2-3 clicks and then 30+ seconds before more clicks.

I'm not sure if it would be the SFR or the board with the relays in question. Any help is appreciated.

 

[Dan O.]

Power to the bake element (240V) will be between the terminal marked "Bake" and either L1 or L2. When on Bake there should be 240 volts between them to power the bake element.

Sometimes 2-3 clicks and then 30+ seconds before more clicks.

I would think that is likely the problem. I the relay should usually close and stay closed while baking (ie. one click).

JMO

Dan O.