First thang to do is check the FUSE.
If it is open the dryer will run but no power will get to the gas assembly.
If the fuse is fine then you might have a bad ignitor or open flame detector.
When the control thermostat is cool it closes contacts and sends power to the gas assembly. The flame detect, ignitor and coils are all powered up. The coils won't work though until the resistance n the circuit changes. For the resistance to change the flame detect and ignitor have to do their thang, then drop out. The coils are all loosey goosey with the rush of power and open up. The raw gas hits the screaming hot ignitor and Booyah!! Houston we has ignition! In about a minute the temp is warm enough in the blower housing to open the control thermostat and the flame is shut down. The clothes keep on absorbing the heat till temp in the blower housing cools down enough to kick in the afterburners again on this bad boy.
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