Gas Dryer Questions

[george7941]

LG DLGX3886C. High limit stat failed

1) Are Supco parts good or should I stay with LG parts?

2) The resettable stats - if they tripped once, should they be replaced instead of resetting them, after repairing the overheating that led them to trip?

3) I checked the natural gas pressure at the tapping on the side of the gas valve and it was 3.8 inches water column. Does that seem about right?

4) The Flow Sense test always displays 4 bars, indicating severe restriction. I cleaned out all the lint in the dryer after pulling off the duct from the lint filter to the blower impeller. There is strong airflow from the back of the dryer with the exhaust duct disconnected. I checked the exhaust duct and the vent cap and they are all clear. So I hooked up twelve feet of 4 in plastic duct that I had to the back of the dryer and ran it outside. The plastic duct was stretched so it had a somewhat smooth inner wall and yet the Flow Sense test indicated blockage. It makes me think there is a defect in the test on this particular machine.

5) I have not replaced the thermistor yet because its resistance values match specifications when cold, warm and hot. Is it possible for the thermistor to be defective when it passes a bench test? Also when conducting the Diagnostic test, the correct exhaust temperature is displayed on the screen. The temperature slowly climbs from 24C once the flame is established all the way to 74c and then the gas valve shuts off and the temperature slowly falls. In spite of all this, could the thermistor be defective and fail intermittently causing the high limit stat to open?

[evaappliance]

56 minutes ago, george7941 said:

and the temperature slowly falls

If the temperature falls slowly on a gas dryer when the valve shuts off , I think there is still some kind of airflow issue 

[Adirondack Bob]

Try running it with the lint filter removed- just to rule it out.

[Adirondack Bob]

1 hour ago, george7941 said:

2) The resettable stats - if they tripped once, should they be replaced instead of resetting them, after repairing the overheating that led them to trip?

Only experience for me is on the Bosch dryers- I've tried resetting them only to be called backed out. 

Replace them and no more call backs.