AER5630BAW F9E0 Fault: Electrical Fire

[landon20]

Model Number

AER5630BAW

Brand

Amana

Age

6-10 years

Amana AER5630BAW Electric range.

Surface and oven did not produce heat after 20 minutes of use. A chemical like smell was identified, but could not be sourced. The chemical smell may be a result of the smell of cooked food and melted wire blending in the air.
Turning off the burners caused the appliance to go dark. Turning any burner on would display a flashing clock with "6:31" displayed for 15 seconds. Fault code F9E0 would display with an audible tone until the range went dark again from setting the burner knob to 0/off.

Moving the appliance is what caused the electrical fire. Heavy arcing/sparks were observed from the rear. Smoke and fumes were present immediately, and the fire department was called. The arcing and smoke intensified as they arrived and attempted to move it. Main power to our home had to be cut temporarily. Not sure why that wasn't done first.

The back panel of the appliance shows a black wire going to a lead. The lead appears to be shorted and burned up, including the insulation near the remaining red and white wires. The metal below the 3 leads were discolored due to heat and sparks.
We are all safe, including the home.

I do not understand why or how this short occured. There were no recent power issues such as a surge, spike, breaker trip or power outage.

 

[rickgburton]

I do not understand why or how this short occured.

It's common on older electric ranges and dryers to occasionally have a wire short to ground. What's not common is a fire caused by a short. That's what circuit breakers are for. As soon as a short is detected the 40 amp breaker opens the circuit. Depending the age of your breaker box, if the 40 amp breaker didn't open the main 100 amp breaker would open the entire circuit to the house.

 

[landon20]

That's the issue. The breaker did not open any circuit. We had to manually hit the main so the fire department could safely disconnect the range.
On a semi-related note, we will be keeping a contractor in touch to inspect our wiring and breakers. Something did not do their job last night.

 

[rickgburton]

I think the problem is now both the range and circuit breaker box. The circuit breakers didn't do their job

 

[Jake]

I agree, the circuit breakers should of tripped.

Did you remove the back panel of your range and see this at your terminal block where your power cord connects to:

(click to enlarge)


Here's the terminal block for your model(Video Included):
WPW10245259 Terminal Block


Jake

 

[landon20]

Hi Jake.
Yes, that is exactly what we saw. After the firefighters dragged the range outside, the panel cover was removed to inspect the terminal block. The ground terminal and wire were observed to be burned up as shown in your image.

 

[Jake]

Yes, Rick and I have seen that many times in our 30 plus years of career techs.

The reason it happens is because who ever installed the range and put the power cord on the terminal block didn't tighten the terminal block nuts/screws tight enough, they have to be super tight, or they will arc and burn overtime.

Jake

 

[rickgburton]

If they aren't on really tight, over time the heat from current flow causes the metal nuts to expand and contract enough times to actually loosen the nut.