Mr. Mike,
Is the red LED on top of the solenoid lighting up at all during the start cycle? If not, you are not getting a turn on voltage from the ECU or the solenoid itself has gone bad. I would also recommend Kelly Williams with PST in Canada he is the man with turbine problems. He has been with them longer than anyone else and is a bulldog with a problem.

BTW the straight in through a one way valve works fine. Just be sure you don't get liquid propane directly into the turbine, It will cause a very hot start.