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Parts for Jenn-Air JDR8895AAB Range - AppliancePartsPros.com

See the attachment for the tech sheet.
[COLOR="Blue"]
Is it a relay? Where is it located?[/COLOR]
It could be but the relay is on the oven control board.
May also be a problem woth the electronics that controls the relay.

[COLOR="Blue"] I've disconnected the broiler element for now. Is that ok?[/COLOR]
All depends if you disconnected it in such a way that nothing can short out to the frame. If that is OK then having it disconnected will at least let you use the other oven.

Note that the oven will not work correctly with the broil element disconnected.
It is used during pre-heat and also during bake. This gives a faster pre-heat and also a more even temperature gradient in the oven when in bake mode.

[COLOR="Blue"]Could it be possible that the heating element is shorting when it heats up?[/COLOR]
Yes it is possible but there are a couple things you have to look for.

The element works on 240 volts so the ground/frame is not normally part of the circuit.

So if it is shorted to grond keeping the element on there are a couple ways it can do this.

1. It could short out to one of it's holders. In this case only part of the element will get hot.

2. A wire ore one side of the element may short to ground. In this case the element will stay on but not get red hot as it is only getting 120 volts instead of the required 240 volts.
Depending on the element it may still get red hot but it will take a long time to get there.