Expansion valve failure?

Today I disconnected the line from the dryer to the expansion valve and noticed some crud in the hose. Cleaned the hose out with some a/c flush solvent took out the dryer and looked inside and saw a bunch of crud. Took off the expansion valve and bunch of crud at the inlet and some on the outlet side. I tried to see if I could get air to go through the valve and no air would go through. Warmed up the end of the valve with a heat gun too see if it would open and it would not open or is filled with crud. Good news is all the other lines and evaporator and condenser were free of crud. So it looks like the crud got stuck in the expansion valve clogging it up. I am guessing the dryer was the main cause.