Thermador Range not maintaining temperature and other issues

[Dard]

I have a 48" Thermador dual fuel range PRD48JDSGU/12 that was purchase new in 2020. We did not install until 2022.  When first powered up, message on control center flashes Thermadors 800 number and a message to call. All features of the oven were disabled.  Called Thermador, was on hold numerous times over 30 minutes.  Finally decided to power off the unit and turn back on.  After a few attempts,  the message went away and all was good. So we thought......    Since the roar of the oven fan is so loud that it severely affects my wife's hearing aids, we seldom used the ovens.  When we do, I have noticed things not baking properly.  We purchased a high quality external read thermometer to see what was going on.  If set on 350, it was only reaching 325 then without warning it takes off to 450 (probably higher if I had not turned oven off).  In order to do any baking, we must watch our thermometer and constantly open the door and adjust the temperature setting.  This is the case for both ovens. Trust me, it is not a situation of just needing to calibrate the settings.   After doing some looking around online, it sounds like a Range oven Control Board rather than a temperature sensor since it affects both ovens.  Am I on the right track?  If so, that part comes up as BSH-00619016 which is listed as a fixing kit.  What exactly does it fix?  Some sites show this part number as a Simmer Control Board.  Since the unit is now out of warranty (my fault, I assumed that a $15,000 range would have more than a 2 year warranty) I am hoping to replace the part myself. Does it also need a main control board?    I was able to quiet the fans by reattaching both using rubber isolation washers. Thermador neglected to secure either fan very well thus the loud noise. The Steam oven fan was ok-     It is a beautiful range- The burners work great.  But, our Thanskgiving is about to be ruined if I can't get the correct part ordered.  Thanks for your help.  

[Daniel.A]

The part you listed is a Simmer control board. That doesn't hold any bearing on the oven operations.

I just looked over the wiring diagram for this. For the sake of being thorough, the oven temperature sensor should test at 1080 ohms at room temp (70 degrees).

If you're going to replace a board, it's likely this one: 10008059

[Dard]

Thank you so much for the information. I will order the board today and let you know the outcome. Of course, I will test the temp sensor first.   

 

[dfphoto]

You really need to be a technical person to work on this, I'm looking at it and the board is not easy to access... if this is 240V that's dangerous.... I don't know if I would want to work on it myself...

[dfphoto]

List of tools

Power Drivers
If using a power driver, set the clutch to the lowest setting
 ̧ Flat blade screwdrivers: large, small
 ̧ Precision flat-blade screwdriver with a high-strength blade,
1/8 inch (3.0 mm) wide, .020 inch (0.50 mm) thickness tip  ̧ Drivers: T-10, T-20, T-27, T-30
 ̧ 2 foot long rachet extension
 ̧ Rachet with 6-inch long (min.) swivel head extension
 ̧ 6 inch long (min.) flex extension  ̧ 5/16 inch deep-well socket
 ̧ 1/4 inch nut driver
 ̧ Adjustable wrenches (2)
 ̧ Strap wrench
 ̧ Open-end wrench sizes: 1/4 inch, 9 mm, 11 mm, 1/2 inch,
9/16 inch, 5/8 inch, 3/4 inch, 5/16 inch  ̧ Pipe wrench
 ̧ Needle-nose pliers
 ̧ Clean putty knife
 ̧ Protective gloves
 ̧ Gas leak test equipment
 ̧ Pipe sealant
 ̧ Small mirror
 ̧ Air lifter / air dolly
 ̧ Floor protection
 ̧ Protective eye wear (such as glasses, goggles)
 ̧ Flashlight
 ̧ Amp meter
 ̧ Thermometer with thermocouple leads
 ̧ Multimeter
 ̧ Clean, non-abrasive cleaning cloth & flexible brush

[Dard]

I am going to give this range one more chance before kicking it to the curb.  After checking the temperature sensor then replacing the control board (10008059) I was hopeful that we could prepare our Thanksgiving dinner using our beautiful Thermador oven.  No such luck.  When the temperature is set, and the oven begins to heat, the large temp gauge continues to show the actual temp until set point is reached.  All is good until the door is opened to put the turkey in and the 100 degree loss is never regained.  At this point, if the temp is increased, the large temp gauge shows the set temp, not actual temp but never reaches actual temp- by 100 degrees or more.  It seems to get stuck after it first heats up.  I tried turning the oven off and restarting the cycle but it would not budge.  Any other advise or test would be greatly appreciated.  Also, knowing if the large temp gauge is supposed to show set temp or actual temp and is it normal to show set temp during initial warm up?  Luckily we still had our highly accurate and dependable all gas Electrolux range in an apartment so all was not lost.  

[Nathaniel Peterson]

On 11/24/2023 at 9:30 AM, Dard said:

I am going to give this range one more chance before kicking it to the curb.  After checking the temperature sensor then replacing the control board (10008059) I was hopeful that we could prepare our Thanksgiving dinner using our beautiful Thermador oven.  No such luck.  When the temperature is set, and the oven begins to heat, the large temp gauge continues to show the actual temp until set point is reached.  All is good until the door is opened to put the turkey in and the 100 degree loss is never regained.  At this point, if the temp is increased, the large temp gauge shows the set temp, not actual temp but never reaches actual temp- by 100 degrees or more.  It seems to get stuck after it first heats up.  I tried turning the oven off and restarting the cycle but it would not budge.  Any other advise or test would be greatly appreciated.  Also, knowing if the large temp gauge is supposed to show set temp or actual temp and is it normal to show set temp during initial warm up?  Luckily we still had our highly accurate and dependable all gas Electrolux range in an apartment so all was not lost.  

I would seriously take a look at all the wiring and check for any rodent damage. Thermador ranges while not impossible usually don't have issues right out of the box. For both ovens to have issues has to be something in common with the two. I bet there's a wire with barely any connection going through it. I would be checking the back panel and underneath the cooktop area. 

[Dard]

Update-
We had a certified tech attempt to diagnose the issue. He verified temps fluctuating over 100 degrees, broiler setting working intermittently etc. He checked for any loose wire connections and consistent power coming to range among other diagnostic tests. His conclusion- enjoy the cooktop and continue using the toaster oven. There is nothing more to be done beyond buying a new range. The next will not be a Thermador. 

[dfphoto]

That guy does not sound 100% what  area are  you in

[CBW]

I have the same range. And your problems are almost identical to mine other than my temperature never jumps high. I did have a certified technician come today. It is the third time. I am also out of my warranty. So I don’t want to fix anything that I’m not certain of. he recommended if I adjust the temperature to make sure that I turn all settings to off as a reset and then set the temperature. I have been running cycles throughout the day having it jump up and down and resetting the dials in between. I think I have had some success. We will see when i,  cook something back to back at different temperatures. 
 

I’m crossing my fingers that this will work. Let me know if you have other solutions that you have found.

[dfphoto]

I re-read this wondering if this has an air leak on the doors or the temp sensor... I was working on a thermador 36 a few weeks ago and even though you had 3 techs that doesn't mean they were as qualified as some on this forum... Excluding myself.

I would make sure to check

Oven temperature Potentiometer / Thermostat 50K Ohm Potentiometer Varies resistance to control board based upon desired temperature 0-2500Ω on off 20-21kΩ at 350F see if you  get that.

[Dard]

On 5/7/2024 at 10:03 PM, CBW said:

I have the same range. And your problems are almost identical to mine other than my temperature never jumps high. I did have a certified technician come today. It is the third time. I am also out of my warranty. So I don’t want to fix anything that I’m not certain of. he recommended if I adjust the temperature to make sure that I turn all settings to off as a reset and then set the temperature. I have been running cycles throughout the day having it jump up and down and resetting the dials in between. I think I have had some success. We will see when i,  cook something back to back at different temperatures. 
 

I’m crossing my fingers that this will work. Let me know if you have other solutions that you have found.

Curious to know if you are still having issues- If not, what was your solution?  I had to walk away for a while but Thanksgiving is coming again...... Hoping not to ruin yet another meal.