I've got my propane setup hooked up and it won't start and I think it's possibly the vacuum hose aren't right? It's a 450 OHG mixer and a Model E vaporizer with an electric lockout. I know it's getting propane past the lockout, but it just doesn't seem to want to fire at all. Do I need the "BAL" port on the vaporizer hooked to anything? Any other ideas or suggestions would be appreciatted.