Ran into this yesterday and it's a mystery to me how it cracked. It's a RainJet RJ711. I noticed the installer used some kind of pipe joint compound instead of Teflon tape... the other 7 valves of the same vintage on the property are fine. It hasn't been cold enough for freezing, and these are sheltered anyway. No kids, but they have a 160 lb. 3/4 wolf 1/4 malamute beast (very friendly actually, and handsome) but I can't imagine he would have been that rambunctious because the 2 valves just next to it are fine. The valve was less than a foot from the house wall. Any thoughts? BTW the pipe shattered when I went to cut it. Just one more reson to use TOE nipples (UV resistance).