I have a maytag bravos series 300 gas dryer that runs fine and air is coming out the vent, but there isn't any heat.

You need a new heating coil

Maytag Bravos 7.0 Cu. Ft. Electric Dryer F73 - Questions ...

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have a bravo dryer , wont start shows error code f73 ? lights come on but dryer ... I think there was an F73 or F93 error message but we did not write it down.

Most likely needs a new thermostat. Go online to find instructions on replacement. Make sure it is unplugged. I don't think it is too difficult to do yourself.

possibly a thermistor or cycling thermostat gone bad

Those sensor bars can become faulty and that is probably the problem. Try cleaning them off with a clean rag. Good Luck!

Here is a link to maytag dryer repairs http://apcoappliancerepair.wordpress.com/?s=maytag+dryer . The most common problem is the thermal fuse. My question is. Does the heating element start to light. If not...... and you have changed the ignitor and thermal fuse. Then check the flame sensor to see if there is continuity threw it. Power to the gas coils and ignitor runs threw the flame sensor. CLICK HERE to see a flame sensor on a GE dryer. They are the same on most units but Maytag will be on the opposite side of burner chamber.

You will need to clean the "internal duct work" for any blockage.

You will need to check all the duct work for lint buildup. This is the reason clothes won't dry or take a few cycles to dry.

remove the back,, the fan is located on the rear of the motor shaft and has reverse threads, either it is a slip on one with a clamp that has come off, or its running and you just can't tell, either way you may want to check it,, as always ,, be very careful as you do this,, don't touch anything that is connected to electrical

Older machines have problems with these coils.

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