| When a gas valve shuts down so quickly, it can be caused by faulty valve coils, but it's usually due to a reduction in airflow. When the burner lights, the flame should be pulled almost straight back through the burner tube. If the flame curls up and comes anywhere near the high limit thermostat, the burner will almost instantly shut down. Disconnect the vent from the back of the dryer and start the dryer. Watch the flame characteristics when the duct is removed and reconnected. That will tell you if the problem is in the vent. If there is no visible difference in either condition, then check the felt drum seals around the front and rear of the interior drum, and also check that the door gasket is still intact. Make sure the lint trap is clean, and you might even wash it with 409 or some other cleaner. I don't recall having this problem continue after these issues are checked and/or corrected. It is slightly possible that the operating thermostat is the problem, but not very likely. If you have further questions, let me know. |