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Replacement parts for WHIRLPOOL RF315PXXN1 | AppliancePartsPros.comHere is a wiring diagram
http://www.servicematters.com/docs/wiring/Wiring%20Sheet%20-%203181470.pdf[COLOR="Blue"]Is it possible that the element melted at a weak point due to a scratch or other defect at the spot of melting, or, did the element melt simply because the thermostat failed to shut down the unit and then subsequently melted down at the weakest point.[/COLOR]
It is really hard to make a call on this.
Did you notice if the whole element was glowing bright red or just part of it or just where the fault was.
I know, I probably would not have noticed as I would be in a panic to shut the unit down.
If it was the whole element glowing I would replace the thermostat.
I am assuming you were able to shut it down by just turning the temp. control.
If yes then at least you know that the thermostat's contacts are not welded together.
Sometimes an element can fail at the feet, this then provides a path from the element connection through part of the element down the foot and to the frame. This is 120 volts but is not controlled by the thermostat so will run wide open.
Be sure to unplug the unit when working on it, 240 volts is lethal.
I would disconnect the thermostat wires and check the contacts in the thermostat. Use the lowest setting on your meter and short the leads together before measuring so you know what a true 0 ohms reading is.
Some meters have a small 0 reading offset.
Measure 1 to 2 and 1 to 3, both should be 0 ohms if not it is an indication of dirty or pitted contacts which can cause the contacts to stick closed.
You could also remove the thermostat and then take it to another oven, place the capillary end in this oven and monitor the 1 to 3 contacts (bake) to see if the open close reliably.
Hopefully others will jump in with opinions and suggestions.
Perhaps the $108.00 is wirth it just for your peace of mind.
If you do not own a meter, I would suggest you purchase a one. You can get a decent digital multimeter for under $20.00. You do not need fancy though it is nice if the leads are a couple feet long.
If it saves ordering one unnecessary part it has paid for itself and you end up owning a useful tool.
Most places will not let you return electrical parts so if you order it, you own it.
A couple things to watch when measuring ohms and continuity
1. Always remove power from the machine otherwise you could blow your meter.
2. Always disconnect at least one side of any device you are checking. This eliminates the possibility of measuring an alternate/parallel circuit path.
3. When checking for closed contacts and continuity use the lowest scale (Usually 200 ohms). Then try higher scales. This scale is 0 to 200 ohms so if the device you are measuring is 300 ohms this scale would show an open circuit which it is not, you are just measuring outside the scale's dynamic range.
There is a good STICKY at the start of this forum about it's use.