I've already tested all fuses and thermostats as well as replaced the gas valve solenoids. Here's a little history on the problem:

It started out with no heat in the dryer. I tested everything for continuity, which all checked out OK. The issue was that the Ignitor was glowing hot but then faded out without ignition. I replaced the gas valve solenoids, which fixed the problem for about a week.

Now the issue is that the ignitor is not glowing up at all.