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Parts for Crosley CDE20T7W Dryer - AppliancePartsPros.com

Sorry but I do not understand your post, could you please expain the problem differently.

[COLOR="Blue"]The dryers runs for 15 mins and shuts off.[/COLOR]
Is it shutting off because the timer advances to Off?
Does the trimer advance or does it stay at the same position?
[COLOR="Blue"]
it is not the timer, Heating elements.[/COLOR]
How do you know?
Did you replace these parts?

[COLOR="Blue"]if I set it for 15 it shuts off and buzzes.[/COLOR]
Is this in timed dry?
Does it run the 15 minutes, timer gets to Off and then it shuts down?
OR
It shuts down right away if the timer is at this setting?

Can the unit be restarted as soon as it shuts off or do you have to wait several minutes before it will restart?
What do you have to do to get it to restart?
Is it just a matter of pushing the start button?

I am stumped on this one.

The timer gets power through different circuit paths when in timed dry and auto modes.
Timed Dry is Neutral through the M/TM timer contacts, the timer motor and then L/M contacts to power.
Auto is L2 , centrifugal switch , heater coil , resistor , A/TM timer contacts , timer motor , M/L contacts to L1 power. Note that the timer advances when the heater is off.

I cannot see anything in the circuit that would cause it to shut off other than the timer. At least anything that would consistently shut off after 15 minutes.

A common cause of a unit shutting down is the motor overheating and tripping it's internal breaker. You then have to wait for the motor to cool down and the breaker to reset before you can restart the unit.
But you said that it restarts right away so it cannot be the motor.

Another common problem can be if the door is not closing properly. Then when clothes hit the door it opens a little and opens the door switch shutting the unit off but again this would not be consistently 15 minutes.