The easiest way to reduce the water pressure is to just not open the
valve all the way. This isn't a precision application: a factor of two
in application rate is within reason.



Steve Wolfe wrote:
...If the water pressure coming from the main is significantly higher than
what the sprinkling system will use, then run high-pressure along the long
run, and put a regulator at the other end of it. In my area, the water
pressure fluctuates between 95 and 105 PSI, so it wouldn't be a problem for
me - but I realize that not everyone else is so lucky. : )

Some people don't even use a regulator on their sprinkler systems, they
just hook 12 or more heads on a single circuit. With all of that flow and
the restriction of 3/4" pipes, it ends up dropping the pressure enough that
heads don't blow up... but the water hammer is unbelievable!

steve