Here are your parts
Parts for Maytag NED7200TW10 Dryer - AppliancePartsPros.comSee the attachment for the tech sheet.
Since the heater runs off of the 240 and everything else runs off of 120 the first thing to do is check your power.
Try flipping the breaker off/on slowly a couple times. Sometimes you can loose half the line without actually tripping the breaker.
Check the voltage at the plug
L1 to L2 should be 240 volts
L1 to Neutral and L2 to Neutral, both should be 120 volts.
If OK
Unplug the unit and check the wires at the terminal strip in the machine to make sure none are loose or burned out
If OK
Check the power at the terminal strip.
Do this with the heater off and on.
[COLOR="Red"]
Be careful as 240 volts is lethal !!![/COLOR]
If you have 240 then unplug the unit and check the heating coil, hi-limit thermostat and the thermal cut-off for resistance.
Note : If the cut-off is open then there are other tests you should do before replacing it.
If the above parts are OK then check the thermistor for resistance.
If it is OK unplug the wires for the heater relay contacts and check across the contacts. Should be infinite ohms (open). If closed you may have to replace the board as the relay contacts are welded together. You may be able to just replace the heater relay if you have a little electronics soldering experience and can find the relay.
If the relay checks out OK then you have two possible causes.
1. The control board is shot and is keeping the heater relay closed.
2. The motor's centrifugal switch for the motor is not closing. Check that the motor is clean. One way to confirm a bad switch is to short the wires to the switch together. Plug the unit in and give it a try. Just be sure that the wires cannot short to anything else (tape them) and that they cannot get caught by a moving part.
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.
4. When you start always short the meter leads together. This will tell you that the meter is working and if there is any 0 offset.
There is a good STICKY at the start of this forum about it's use.