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Replacement parts for WHIRLPOOL LXE5700W0 | AppliancePartsPros.com

First I would try turning the breaker off/on slowly a couples times. Sometimes you can loose half the line without tripping the breaker and the heater requires the full 240 volts. The motor only requires 120.
If this does not work I would measure it with a meter.
L1 to L2 should be 140 volts
L1 to Neutral and L2 to Neutral should be 120 volts.

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.