How it works: Gas assembly

Power is sent from the temp control to the gas assembly which is the ignitor the flame sensor and the solenoid coils. All of these are wired together in the same circuit. The flame sensor must have continuity. If it is open nothing else will happen. Flame sensor has nothing to do with the actual flame that comes out the burner. What it senses is the heat from the ignitor. When the ignitor gets hot enough it bends a bi-metal in the flame sensor. So we now have power on and the sensor is good the next thing that happens is the coils and ignitor are energized. The ignitor begins to glow, if it does not nothing else will happen ,nope the gas won't come out either even though the y too are energized, Why? Because the resistance in the ignitor has first change in the circuit and it needs to get hot to do it so the the holding coil will be energized. get that? Wait their is more. As the ignitor gets hot it bends the bi-metal in the flame sensor and that kills the power going to the ignitor. The coils get the amount of amp draw that the ignitor was hogging and yank open the gas gates. The raw gas comes out and ignites. The heat from this flame keeps the ignitor hot. It is now itself a safety device. If no flame were to ignite. The ignitor would cool down and close the gas gates. Got that? Complicated ain't it?:D
If the ignitor come on and the bi-metal flame sensor shuts it down and ignition occurs but the dryer quits heating then them coils need replacing because they are getting hot and quitting. A common occurrence on these gas dryers. The signal LED location.doc (541kb) downloaded 68 time(s).