On Friday, June 20, 2014 11:58:40 PM UTC-4, HerHusband wrote:
Perce,



I'm replacing the indoor section of the plumbing that feeds our

sprinkler system. The old PVC threaded fittings screwed in far enough

that the shoulder of the fitting contacted the body of the vacuum

breaker, but the new fittings bottom in the VB with more than 1/2 in.

of thread still showing. Would it be a good idea to cut enough off the

threaded portion of the PVC fittings so that none of the threaded part

(which I assume is the weakest part) is unsupported by the body of the

VB?



Having exposed thread won't cause any problems, in fact that's how most

threaded fittings end up.



+1

They are tapered and are not supposed to go all the way in.
Only far enough to make them tight and not leak.