I thought orbit was a brand to spend on,. But not for these...  They are not reliable and don't last.  I have the 57223 models which I think are the same as these.  Valve sucks and won't turn on.  Just thump thump thump until you loosen the solenoid.  Thumping stops, valve works, but then solenoid leaks.  Tighten the solenoid and when you close and reopen the valve, the thump thump thump comes back.  It's like is trying to open the valve, but can't quite get it opened.  Maybe the solenoid plunger is slightly to long ?  Just not reliable.  Is there a recall on these, or an upgraded part that doesn't have this problem?  All 4 of mine have this problem when I first start using them after winter is over. And they sometimes act up randomly throughout the year..