KitchenAid Range oven taking to long to preheat.#KERS505XSS02

[Soso]

 I have a Kitchenaid range with a smaller oven on the top and a larger oven on the bottom. Model #KERS505XSS02. The lower oven takes 20-25 minutes to preheat to 350 deg. The upper oven gets to that temperature in 5 minutes. Smaller oven I know. I am wondering about the lower oven. I think it should reach a 350 deg. temperature much faster than that. Using regular cook or convection it is the same. I have pulled the back off and put a ohm meter on the heating elements and all seem fine. Also on the oven thermostat  and it checked at 10.84. Any ideas what could be taking it so long to preheat?

Thanks for your help.

[DurhamAppliance]

does the broil setting work on the bottom oven?  Broil is used to assist  the bake element during preheat.  If your broil does not work,  probably a bad high limit fuse which is in series with the broil element. 

[Soso]

Yes the broil on the lower oven does work. I checked it on its own in the bake position and while preheating. It worked both times.

[Soso]

I meant to say I checked it on its own in the broil setting and in the preheat position and it worked both times.

[Hiroshi]

it is hard to prove with a meter, and I have had many conversations on the subject over sushi, but elements do get to be a bit sluggish over years of usage- some elements actually "sing" in a way I can hear as they heat and quickly get red-hot, but many do not sing and take longer to "cherry out." I cannot define all the facets of this phenomenon, but if all the elements 'cherry' in the same amount of time, heating differences can be attributed to oven cavity size and airflow. If the elements take varying amounts of time to 'cherry,' I think it is a matter of relative sluggishness in the elements under observation.

[johntech]

What are you using to measure temperature?. 

[Soso]

As far as checking the broil and bake elements. I checked it visually while it was on and with a Fluke ohm meter on the back for continuity. Turning power off and pulling one wire off before checking. 

I was wondering if the control board could be the problem in not allowing it to preheat properly? 

This is not that old of a range and has been like this sense it was new. It has not had a lot of use. Maybe that is normal for this oven. I have compared a different double oven, different brand in another home and both ovens will preheat in five minuets to 350 degrees. So something seems not quit right with this Range.

[Soso]

I am using thermal heat gun to check temperatures and inside the oven is trending about 20 deg. higher than what the control board reads as the temperature goes up. 

[16345Ed]

Does your fluke has thermal probe?

 

use that to observe temp. You need to get an average over time. Ovens don't maintain temp they cycle. 

[johntech]

I can't really tell by the part break down but if it has a conceited bake element (an element that is not visible  inside the oven cavity) then I would say it is normal operation. They can take 20+ minutes to preheat.

[Soso]

It does have a cancelled bake element. I will assume it to be normal even tough it seems really slow. Thank you for your help.  

[trip2]

I believe Soso probably answered my question and concern.  I have a KitchenAid Gas Range/Double Oven - 11 years old. Until recently, the top oven would preheat BAKE to any desired temp; now, when preheat (if set at 375), it only heats to 225.  My wife accidentally enabled the top oven to preheat BAKE to 375 by using BROIL, then switching  to BAKE and setting the desired preheat temp.  I did not see these preheat instructions (using BROIL to assist BAKE) in our KitchenAid 'Use and Care Guide.'