My Thermador PDR304ZS electric oven won’t stay on.
(It is part of a dual fuel range.)
It will heat up to the desired (set) temperature
with no problem. But as the oven cools it will never
start up again to maintain the heat at the desired
temperature.
The indicator lights may be of interest:
The “oven on” indicator light is on while the oven heats
up, but it goes off when the oven reaches the desired
temperature. It stays off. (the operation manual says
it should stay on, while the oven is on.)
The “heating” indicator light is on while the oven heats
up. It goes off when the oven reaches the desired
temperature. After the oven cools for a bit, it goes back
on, but the oven does not heat. The “heating” light then
stays on, but the oven never does heat up.
I replaced the control board, but that did not help.
Any help would be appreciated, thanks in advance !
The control that you replaced, was it the one at the link below?
Bosch 00676192 Pc Board - AppliancePartsPros.com
Yes, it that was the part number. control board part 676192.
Thank you. When the oven is supposed to turn back on after it has preheated, do you hear any clicking from the relays?
I did not hear any relay clicking sounds.
But will restart the oven and listen carefully.
The thermador oven fan is pretty loud.
If I do not hear the relay, what does that mean ?
After running the oven again, I do not hear any relay
clicking sound(s) when the oven is supposed to turn
back on. (we do hear relay clicking sounds only when
we first turn the oven on.)
If the relays are not closing to energize the elements, the oven potentiometer may be faulty. Let me know if you hear any clicking when it is supposed to be heating up again.
We don’t hear any relay clicking sounds.
On some earlier threads I had read about faulty relay
connections, and one of the relay connections was
loose and very carbonized/burnt, so I tried to clean it as
best I could with sand paper. Also on the previous control
board this relay connector was corroded and burnt looking.
The relay on the new board is burnt?
No, the relay connector on the new board looks fine.
On the old board I replaced, it looked burnt.
Okay, so the new should be good. How about the wires on that relay, are they burnt or discolored at all?
One of the wires was discolored. But on that wire, I tried
to clean the connector by rubbing it with sand paper and
closing the connection gap a bit to make a more solid connection.
That connection may be the source of your trouble. It was probably the wire that was connected to the output terminal of the burnt relay. I would replace that terminal and see if it makes a difference. Did you get a chance to listen for the relays?
I don’t hear any relays.
I can fix the terminal, but what exactly do you mean replace the terminal?
Do you mean replace the connector on the wire that goes to the
terminal??
Also, what about the “oven on” indicator light going off. Does that
indicate some kind problem?? What would make that light go off?
The terminal on the wire that is discolored that you tried to tighten up is the one I mean to replace. That main board controls the oven, the sensor just tells it what temperature (by way of a resistance reading) and the potentiometer tells it what resistance it should be at. It still seems that the board may have issues.
OK, thanks for all the info. I will replace the connector later today.
I will post later to let you and the readers know if the fix works.
Have a good weekend !
I did resolve this issue, in short:
The oven heats up to the desired temperature and then does not maintain
that temperature, the oven slowly cools down.
Here is what was happening, on the initial heating both the broil
and the oven heating element are on to quickly heat up the oven to
the cooking temperature. After the cooking temperature is reached
only the oven heating element is used to maintain the cooking heat.
The broil element is no longer used. (the oven is on bake or convection bake, not on broil). When I checked and found that the oven heating
element was burnt out (multi-meter said it had infinite resistance).
So the broil element did heat up the oven, but the
oven heating element would not work to maintain the temperature.
I replaced the oven heating element. Now my oven is working again for
me. It all makes sense now.
Hope this info helps somebody. Good Luck with your oven repairs out there !!