Rookie ? On Reducing Valves

[PM5K]

Why not just open the main valve partially to reduce pressure?

I can see how that might not help with large fluctuations where even at partially open the pressure exceeds what you desire.

Is volume part of this equation?

Would both options handle a large demand for water on the customer side the same way, or with the same results?

What else am I missing?

 

[Reach4]

A partially open valve will not reduce pressure at all when there is no flow. It will reduce pressure way too much when there is much water being used.

If you know electronics, that would be analogous to using a resistor instead of a voltage regulator.