Is the dryer just plain not running, or is it running and not drying? Check to make sure the vent is clear, from the dryer all the way to the outside of the house. Also, make sure the bent hose (if you're using a flex hose) is not kinked or otherwise restricted.

Sounds like you have been getting screwed over.
A model number may help others help you.
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I replaced my 7 year old dryer that did not heat. I wanted to have it repaired but the repairman charged me and said there was nothing wrong with the dryer and that I needed to have another 110volt installed and then it would work. I asked him why did it work for 7 years with only 110 volt?[/COLOR]
This person was either ripping you off or just stupid.
You are correct that it ran OK so your problem is either the dryer or the power to the dryer.
It is possible to loose half the line to the dryer but the repair person should have told you exactly what the problem was.

[COLOR="DarkRed"] (no answer) so I hired and paid an electrician. The electrician said that there was no problem with the electrical wires and any dryer would work. I called my power company and they said everything checked out.[/COLOR]
You can assume that the power was OK when they checked it but cannot assume that it is OK now.
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So I bought a new dryer and it worked for 2 months and now it doesn't work. Hired a repairman (under warranty) and he said there is nothing wrong with the dryer. His meter showed that 243 volt is coming from the plug so any dryer should work.[/COLOR]
Did he fully check the power or just the 240?
You need both 240 and 120 to Neutral feeding the dryer.
FYI: Your dryer uses 240 volts, this is two 120 volt supplies with a common Neutral that are 180 degrees out of phase. The motor and usually the timer use one side of the line (120 volts). The heater uses the 240 volts. Basically one side of the line is positive 120 volts while the other side of the line is negative 120 volts so the voltage between them is 240 volts.

[COLOR="DarkRed"]I am out of ideas, everyone says there is nothing wrong buy my dryer doesn't work. I spent hundreds on new dryer and repairmen and now I have to go put money on a card at a laundromat to dry my clothes. I have spoke with several electricians that say it has to be the dryer. But no repairman can fix it. I need help. I really want a dryer that works! I bought this one August 6th 2011[/COLOR]
Without being there I cannot say what the problem now is.
Messing with 240 volts when you have no experience with electrical in not advisable but that is where you have to start.
I am assuming that the motor does not run. On most dryers the L1 side of the line runs the motor (L1 black 120 volts to Neutral white)

Try flipping the breaker off/on slowly a couple times.
Sometimes you can loose half the line without actually tripping the breaker.
If this does nothing, 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.
Be careful as 240 volts is lethal !!![COLOR="Red"]
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The reason you have to do it with the dryer on and off is that in rare occasions you will see the correct power with the unit off but as soon as a load is placed on the line the power drops out. This is often a loose/bad connection somewhere.
It get dangerous trying to check voltages with the dryer shaking!!!

I cannot say for sure as you did not give a model number but the 243 does not matter when it comes to the dryer starting. You need the 120 volt (L1) to Neutral and it is not uncommon to loose Neutral or one side of the line.

Also you cannot assume that because the symptoms are the same that the cause is the same.

You may want to post where you are located and perhaps a regular poster can do a service call for you and finally get this resolved.

Don't give up so easy.

What you need is someone who can check the power out for you with the dryer attached. Think hard if you have a handy friend (DIYer) who knows something about electricity.
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It won't run at all. Except when the technician "cut the wire" and replaced it.[/COLOR]
Would be nice to know what wire he cut?

[COLOR="DarkRed"]He could see how disappointed (not really mad) I was/am. It worked for 2 seconds after he did that and then it did not work. Even more disappointing.[/COLOR]
I misunderstood your earlier post. I thought that this repair person had changed a wire and the unit worked but then he changed it back and it did not.
The above seems to indicate that he changed something and it only worked for 2 minutes and then it stopped. It sounds like he may have blown something in the dryer by modifying the power to the dryer.

All I can suggest is that you try the friend route.
You could also ask friends for a recommendation on a good repair person.
Be sure that they will check both the dryer and the power to the dryer.
Tell them you will not pay till the dryer is up and running.