Took a guess, fixed my dryer for $30 but don't understand why.

DerbyDad03 · 2013-09-24T19:32:08+00:00

My gas dryer had been acting up recently. The clothes would almost dry, but with a front load washer they are not all that wet anyway. Still, it didn't seem like the heat was staying on very long. The other 2 symptoms were these: 1 - On the Timed settings, both heated and air fluff, the timers would advanced normally. However, on the Auto-Sense settings (high heat or low) the timer would advance to about halfway through the range on the dial and then stop. The dryer would then run continuously with no heat, even for hours at a time, until we manually shut it off. 2 - Regardless of what setting we would use, we always had to wait at least 15 minutes after the dryer shut off before the burner would come on. If we tried to start the dryer right after the last load, the drum would spin, the normal click would be heard after about 15 seconds, but the "whoosh" of the burner coming on wouldn't be heard. If we let the dryer sit for about 15 minutes, we'd get the 15 seconds of spinning and then "click-whoosh" as the burner came on. A little research seemed to point to the gas valve solenoids as a possible cause. If the gas turned off too soon, the clothes wouldn't dry completely so the Auto-Sensing mode might not trigger the dial to advance. However, in Timed mode, the timer would advance normally since that setting doesn't care if the clothes are dry or not. That makes sense. A local parts store had the solenoid pair for $30, so I swapped them in and the dryer worked perfectly after that. Everything seems to make sense except for the 15 minute wait time between cycles. What in the gas valve solenoid circuitry, or in a solenoid itself, would cause the dryer to need 15 minutes of rest before the gas would come back on? In either mode, Timed or Auto-Sense, the dryer had more than enough time to cool down since the gas turned off soon after the cycle started. So why did the dryer have to be completely off for 15 minutes before the gas would turn back on?