Blowing out the line will not do any thing if you are not getting gas. If the solinoid is not opening your not getting gas. Fix/verify that works then look for the simply stuff. I would disconnect line after the soliniod then quickly cycle the system if you get gas then your issue is down stream, if you dont you need to check power to soliniod, if you have power then you probably have a bad solinoid.
ps I would suggest if you dont feel comfortable doing this check with an LP serviceman or RV tech
Jim & Debbie England
Do you have Gas? 2015 F350 6.2L CCLB DRW 4.30 axle. 2012 Yellowstone Ridgeline 34RLT Fifth Wheel