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I have an LG range that no heating element works. F7 error code flashes model#Lre30755st. All the lights and buttons work.

I bought this from a lady and she told me that only the 2 front burners did not work so I tried to trouble shoot it and see if it was the elements themselves but it was not that. then I plugged it in and no burner or heating element works at all. there are 3 computer boards on this range 1 power controll board for the oven and 1 power control board for the stove top and then a third that I guess is for main controls. the 2 power control boards both for oven and stove when I try and turn burners on I can here the electric relay click for each burner I try and cut on. I think the power boards are working fine I think it is maybe the power converter or the main board that is defective but dont know how to figure what is wrong out.

Gas Grills , LG , Ranges , Wall Ovens , Appliances
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2 Answers from these members:
Manage My Life
A non working Range is not something any of us want to see. If you are technically handy, this is a good site to get instruction and fix some things yourself. If you do not feel confident doing your own repairs, an option is to visit Sears Home Services and use the scheduler. While you wait for the expert to review your model, you can check the bottom links for some possibilities. Hope this is of help.
by Manage My Life
September 14th, 2011
Answered in 17 minutes
0 votes
Manage My Life
Be sure you have 230 volts across the red and black wires at the terminal block the power cord attaches to. I suspect you have only one line to the range.

It is simpler to check a portion of the range first. Go to the relay board for the bake and broil elements. Check for incoming voltage between the red and black wires. You should have 230 volts all the time.

Set the oven control to bake at 350 degrees and check between the yellow and black wires that go to the bake element. You should have 230 volts. If you have 0 volts, check between the yellow wire that goes to the bake element and the black wire that goes to the terminal block of the range. If you have 230 volts here, the DLB relay on the relay board is bad. This will prevent bake and broil from working.

We can go through the relay board for the cooktop. I think it is best to eliminate one problem at a time.

Be sure to use proper precautions when checking live voltage. If you are not comfortable doing these tests, go to

Home Services

and get a Sears technician to repair the range.
by Manage My Life
September 16th, 2011
0 votes
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