I am trying winterize my landscaping sprinklers. I just moved into my new house and find out this plumbing layout is quite different, I hooked up my 100psi air compressor and tried to blow them out but no luck. I can't get a hold of the old owners so I don't know what to do right now, but snow is coming soon here in Utah.
Update #1: Looks like there is no backflow prevention device.
Thanks a lot!